ON THE FRONTIER 
4 

Hugh L. Dryden 
v I a * 

ON THE FRONTIER 

Flight Research at Dryden, 

1946-1981 

Richard I? Hallion 

The NASA Histo7y Series 

Scientific and Technical Information Branch 1984 

National Aeronautics and Space Administration 

Washington, DC 
One advantage of working in contemporary history is access to participants. During the 

research phase, the author conducted numerous interviews. Subsequently he submitted 

parts of the manuscript to persons who had participated in or closely observed the events 

described. Readers were asked to point out errors of fact and questionable interpretations 

and to provide supporting evidence. The author then made the changes he believed 

justified. The opinions and conclusions set forth in this book are those of the author; no 

official of the agency necessarily endorses them. 

Library of Congress Cataloging in Publication Data 

Hallion, Richard. 

On the frontier. 

(The NASA history series) (NASA SP ; 4303) 

Bibliography: p. 363 

Includes index. 

1. Dryden Flight Research Facility - History. 

I. Title. 11. Series. 111. Series: NASA SP ; 4303. 

TLb21.312.H34 1984 629.1’072079488 83-14136 

For sale by the Superintendent of Documents, U.S. Government Printing Office, DC 

cover) 

20402 (paper 
Contents 

Page 

FOREWORD ............................................... vii 

ACKNOWLEDGMENTS ....................................... ix 

PROLOGUE: A MOST EXOTIC PLACE ........................... xi 

I . EXPLORING THE SUPERSONIC FRONTIER: 1944- 1959 .......... 1 

1 . Confronting the Speed of Sound: 1944- 1948 ........... 3 

2 . Pioneer Days at Muroc: 1948-1950 ................... 23 

3 . Testing the Shapes of Planes to Come: 1950-1956 ...... 41 

4 . Through Mach 2 and 3: 1951-1959 .................. 63 

5 . Testing Service Aircraft: 1953- 1959 .................. 87 

I1 . INTO SPACE: 1959-1981 ............................... 99 

6 . The X-15 Era: 1959-1968 ........................ 101 

7 . Serving Gemini and Apollo: 1962- 1967 .............. 131 

8 . Prelude to Shuttle: The Lifting Bodies. 1962-1976 ..... 147 

9 . Mach 3 Again: 1966-1979 

10 . A Center with Diversity: 1962-1981 

......................... 177 

................. 201 

11 . A Center at the Crossroads: 1976- 1981 .............. 235 

APPENDIX A-Organization Charts. 1948- 198 1 ............... 261 

APPENDIX B-Personnel Summary for FRC/DFRC, Other 

OART/OAST Centers. and NASA as a Whole ..... 273 

APPENDIX C-HSFS/FRC/DFRC Technical Facilities ............ 275 

APPENDIX %Authorized Funding for Research and Program 

Management at FRCIDFRC. Other OART/OAST 

Centers. and NASA .......................... 277 

APPENDIX E-HSFS/FRC/DFRC Research Aircraft. 1947- 1980 . . 279 

APPENDIX F-X- 1 Program Flight Chronology. 1946- 1958 ..... 285 

V 
ON THE FRONTIER 

APPENDIX G-Douglas D . 558 Program Flight Chronology. 

1947-1956 ................................. 299 

APPENDIX H-X-2 Program Flight Chronology. 1954- 1956 .... 315 

APPENDIX I-X-3 Program Flight Chronology. 1954- 1956 ..... 317 

APPENDIX J-X-4 Program Flight Chronology. 1950-1953 ..... 319 

APPENDIX K-X-5 Program Flight Chronology. 1952- 1955 .... 323 

APPENDIX L-XF-92A Program Flight Chronology. 1953 ...... 327 

APPENDIX M-X- 15 Program Flight Chronology. 1959- 1968 ... 329 

APPENDIX N-Lifting Body Program Flight Chronology. 

1966-1975 ................................. 339 

APPENDIX 0-XB - 70A Program Flight Chronology. 

1967-1969 ................................. 347 

APPENDIX P-YF- 12 Program Flight Chronology. 1969- 1978 ... 349 

APPENDIX QSpace - Shuttle Orbiter Approach and Landing 

APPENDIX R-Accident Statistics. 1954- 1975 ................. 359 

A NOTE ON SOURCES ..................................... 361 

SOURCENOTES .......................................... 363 

INDEX .................................................. 377 

THE AUTHOR ........................................... 387 

Tests Program Flight Chronology. 1977 .......... 357 

vi 
Foreword 

A stillness was on the desert. Daylight settled unhurriedly down the 

hilltops bordering the triangular valley. The indigo sky above and to the 

west was pierced with the gleam of a solitary planet and the flicker of an 

occasional second- or third-magnitude star. 

The valley bottom was an immense expanse of flatness. Miles of 

mirror-smooth clay were marred by neither hummock nor furrow. No 

tree or bush could be seen on this seemingly endless waterless lake. No 

sound from animal or bird punctuated the silence. Wild creatures found 

little to attract them on the vast empty platter. It was one of nature’s quiet 

hideaways, an outpost of serenity. 

There were intruders. On the western shore of this “lake,” figures 

scurried around a strange assemblage. A small shark-sleek craft was being 

attached to a much larger mother craft. The shark‘s midsection was banded 

with ice crystals; puffs of ashen vapor wafted upward and disappeared 

into the clear sky. The juxtaposition of ancient geology and modern 

technology, curiously, seemed to fit. 

By the mid-twentieth century, the science of aeronautics had grown to substantial maturity. Aircraft were speeding faster and faster and threatening to outrace 

their own sound. The National Advisory Committee for Aeronautics had a trio of 

laboratories to study the fundamental problems offiight. They had a wide variety of 

test facilities and a cadre of bright, able, and dedicated scientists who had performed with remarkable success over the years surrounding the second World War. 

For the testing of very-high-speed aircraft, however, they needed a new laboratory: 

a laboratory in the sky. 

And so it was that the researchers came to Antelope Valley in 

California, a valley blessed with clear and uncrowded skies, a sparse 

population, and Muroc Dry Lake, a natural aerodrome where runway 

length and direction were, for most practical purposes, unlimiting. 

On the shore of Muroc, NACA established its High-speed Flight 

Station and began its challenge of the unknown. The mysteries were 

numerous and perplexing. The search for solutions was tedious, protracted, and often dangerous. The research methods placed men and 

machines at the boundaries of understanding. On occasion, fine men 

were lost at those boundaries in the pursuit of knowledge. Their sacrifices will be remembered. 

vii 
ON THE FRONTIER 

At the dawn of the Space Age, the researchers on the shore of the 

dry lake were already actively engaged in its planning. After NACA 

became NASA, their considerable contributions were of substantial significance in the evolution of America’s manned spaceflight program. 

This book is the story of those researchers and their efforts. Richard 

Hallion has recorded the history of their flights and captured the spirit of 

a remarkable and unique institution in the evolution of aerospace progress. 

He tells of the place, the projects, and, most important, the people. It is a 

story of men and machines, of success and failure, of time and circumstance. 

I had the pleasure of living some of the events recorded here. I take 

great personal satisfaction in those years, the projects in which I was 

privileged to participate, and the wonderful and able people I worked 

with and whose friendship I cherish. 

October 1983 Neil A. Armstrong 

... 

vi11 
P P * 

Acknowledgments 

This account of flight research at Hugh L. Dryden Flight Research 

Center resulted from cooperation between the History Office of the 

National Aeronautics and Space Administration and the Department of 

Science and Technology of the Smithsonian Institution’s National Air 

and Space Museum. It would have been impossible to undertake and 

complete this study without the support and assistance of a large number 

of persons within NASA, the Smithsonian Institution, and the Departments of Aerospace Engineering and History of the University of 

Maryland. My debt to all of them is great. 

I owe special gratitude to Michael Collins, the former director of the 

National Air and Space Museum; Melvin B. Zisfein, deputy director; and 

assistant directors Howard S. Wolko, Donald S. Lopez, and Frederick 6. 

Durant 111, together with Dr. Tom D. Crouch, Dr. Paul A. Hanle, Dr. 

Robert Friedman, and Dr. Richard Hirsh of the curatorial staff. Staff 

members of the NASM Library, especially Catherine D. Scott and 

Dominick A. Pisano, were most cooperative in locating obscure reference 

materials. The staff of the NASA History Office encouraged me at every 

step. I am especially appreciative of the assistance and cooperation given 

by Dr. Monte D. Wright, Dr. Frank W. Anderson, Dr. Eugene Emme, Dr. 

Alex Roland, Lee Saegesser, Leonard Bruno, Carrie Karegeannes, and 

Nancy Brun. Staff members of the National Archives and Records 

Service, especially John Taylor and Jo Ann Williamson, were of great 

assistance in tracing NACA and NASA record groups. I wish to thank 

Charles Worman of the Air Force Museum, Carl Berger of the Office of 

Air Force History, Dr. Lee M. Pearson of the Naval Air Systems 

Command, and J. Ted Bear of the Air Force Flight Test Center for their 

assistance. I am grateful to the faculty of the University of Maryland for 

assistance and wise counsel, especially Professors Alfred Gessow, John D. 

Anderson, and Jewel B. Barlow of the Department of Aerospace 

Engineering; and Wayne Cole, Keith Olson, and Walter Rundell of the 

Department of History. Professor Roger E. Bilstein of the University of 

Houston at Clear Lake City was most helpful during my research and 

initial writing, as was Professor Richard E. Thomas, director of the Center for Strategic Technology, Texas A & M University. 

ix 
ON THE FRONTIER 

It is, of course, to the participants in this history that I owe my 

greatest debts. With unfailing courtesy, grace, and assistance, the present 

and former personnel of the Dryden Flight Research Center and their 

NASA, Air Force, Navy, and industry counterparts welcomed my every 

inquiry, patiently answered all questions, and assisted in the detailed 

reconstruction of past events. Through them I learned much of the 

flight-testing process and the history of the center-and of the character 

and courage of individuals who test the products of engineering drawing 

boards. Through Ralph Jackson, director of external affairs for the 

Dryden Flight Research Center, I had the opportunity to conduct my 

research in the conducive atmosphere of Dryden during the bustling 

days of the Space Shuttle. It was a refreshing and novel experience for a 

historian; as I examined boxes of records a quarter-century old, the 

rumble of NASA's present experimental aircraft punctuated my research, 

forcibly reminding me that the history of Dryden is far from over. 

Finally, this book is dedicated with affection and respect to the 

memory of Michael R. Swann, a Dryden research pilot of uncommon skill 

and promise, who died in the crash of a sport glider near California City 

on 28 July 1981. 

Richard P. Hallion 

University of Maryland 

August 1981 

X 
Prologue 

A Most Exotic Place 

Northeast of Los Angeles, beyond the coastal range, lies the Mojave 

Desert, the southwestern corner of which is called Antelope Valley. The 

semiarid area produces alfalfa, turkeys, fruit, almonds-and aircraft. 

The clear weather and vast, unrestricted space have lured the aircraft 

industry as flowers draw bees. Politicians have pragmatically dubbed it 

“Aerospace Valley.” Its two major communities, Lancaster and Palmdale, 

cater to the wants and needs of the aerospace community. At Palmdale 

looms “Air Force Plant 42,” where products of Northrop, Lockheed, and 

Rockwell scoot aloft. Here is the home of Rockwell’s Space Shuttle and 

the B-1 strategic bomber. The valley economy would collapse if the 

aerospace industry declined, and citizens are determined not to let that 

happen. “Vote your pocketbook! Ketcham = B-1” read one 1976 

election poster, and such logic makes sense to desert residents. Lancaster’s 

economic heart is located at the Air Force Flight Test Center and NASA’s 

Hugh L. Dryden Flight Research Center, on the shores of Rogers Dry 

Lake at Edwards Air Force Base. Lancaster received its name in 1887 

from homesick Pennsylvania Amish settlers. In 1950, it had a population 

of 3924 and was a sleepy desert community where a shopper could go to 

a store in the midst of a work day only to find a “Gone Hunting” sign 

posted on the door. Then came the aerospace boom. A decade later, the 

population hit 30 000. Most Edwards workers, be they Air Force, NASA, 

or private contractors, live in Lancaster. 

North of Lancaster is the tiny community of Rosamond, home of the 

Tropico gold mine, a grubby desert town of unadorned houses and 

mobile homes. “Welcome to Rosamond-Gateway to Progress,” proclaims a black-and-white sign on Sierra Highway. Turn right at Rosamond 

Boulevard, and one is soon rolling toward Edwards, running past the 

smooth baked clay of Rosamond Dry Lake. Ahead, over scrub-covered 

low hills, stretches the vast parched-silt bed of Rogers Dry Lake. 

North of Rosamond and 40 kilometers above Lancaster, the town 

of Mojave hugs open desert between brooding Mount Soledad and the 

Tehachapi range. Mojave was once the terminus for borax-laden mule 

xi 
ON THE FRONTIER 

9. 5 

z P 

0 

7 Los Angeles 

xii 

The western Mojave Desert 
J m B Q 

PROLOGUE 

trains, a brawling, hard-living town. Desert winds sweep across Mojave, 

sometimes overturning trailers and vans, often closing the roads to truck 

traffic, usually blowing powdery grit and tumbleweeds across the land. 

Now the mule trains have been replaced by massive diesel-electric 

locomotives running north and south with long strings of hoppers and 

boxcars paralleling the Sierra Highway, then turning west into Tehachapi. 

In the crisp desert days, they can be seen from afar, snaking like 

caterpillars. At night, their thunderous clatter jars the stillness of the 

desert. Mojave is bleak, barely populous enough to rate a few drive-in 

restaurants. Mojave’s chief attraction is air racing. Occasionally sportsmenpilots gather at the old Marine Corps air station with their revitalized 

Bearcats and Mustangs. Amid the throaty rasp of propellers and the 

occasional screech of a blown engine, they pit themselves against one 

another to the vicarious enjoyment of thousands. 

From Mojave one can turn northwest toward Tehachapi and 

Bakersfield, or bear northeast toward Cantil. Here the road again 

branches: north along the Sierra Nevada range toward China Lake, or 

east to the ghost town of Garlock and the old mining towns of Randsburg 

and Johannesburg. Shadowed by Red Mountain, Garlock had six mills 

processing gold ore from Randsburg, but it fell into disuse at the turn of 

the century. The town’s ramshackle buildings are buffeted by winds that 

race off the El Paso Mountains and whip across the flats of nearby Koehn 

Dry Lake. Traces of half the world’s minerals can be found near 

Randsburg. Its numerous mines-with such names as Napoleon, Olympus, 

and The Big Norse-thrived during the gold boom, then played out. 

Prospectors discovered huge tungsten deposits and frantically worked 

them through World War I and until the postwar tungsten market 

collapsed. Red Mountain’s prodigious silver deposits caused a resurgent 

boom until the vein played out in the late 1920s. Now Randsburg is 

almost a ghost town, its original buildings mixed in among mobile homes. 

“Joburg” is saved from extinction only by being on a highway. 

South of Joburg and Red Mountain is the desert intersection of Four 

Corners. On the flat ride down from the old mining camps, one notices 

only the swell of Fremont Peak in the east; the endless transmission lines 

paralleling the road; and to the west, the Air Force tracking station at 

Boron, its radome sprouting from the ground like a white puffball. Four 

Corners sits astride Highway 58, the route of the Okies immortalized by 

John Steinbeck. South of Four Corners is the route to Victorville and San 

Bernardino, across the San Bernardino Mountains. East of Four Corners 

is Barstow, a major intersection for truckers. 

West of Four Corners on Highway 58 is the little town of Boron, 

where the double crack-crack! of sonic shocks is heard so frequently that 

Boron’s citizens coyly proclaim themselves “The Biggest Boom Town in 

... 

XI11 
ON THE FRONTIER 

America.” Boron’s chief product is sodium tetraborate, better known as 

borax. Introduced into Europe by Marco Polo in the 13th century, borax 

remained an uncommon mineral until the discovery of the Mojave’s 

deposits in the 19th century. The world’s largest open-pit borate mine is 

just outside the town north of the highway. At night, its high-intensity 

lights can be seen for miles; by day, dust hangs low in the sky. West of 

Boron is the little community of North Edwards; like Lancaster, most of 

its citizens are or have been affiliated with Edwards Air Force Base. At 

North Edwards, the traveler can continue west on Highway 58 to Mojave, 

or (if authorized) can turn south, onto Rosamond Boulevard, driving 

down to Edwards, its hangars gleaming in the distance. And here, the 

visitor sees perhaps the weirdest of sights that the desert has to offer: the 

165-square-kilometer bed of Rogers Dry Lake. 

Dry lakes are the flattest of all geological land forms. Rogers Dry 

Lake is a playa, a pluvial lake, one of 120 such lakes in the western United 

States. Pluvial lakes are believed to have first appeared in the Pleistocene 

epoch, about 1.5 billion years ago. Glacial activity dropped temperatures 

and increased precipitation, creating hundreds of pluvial lakes, which 

fluctuate between wet and dry phases. They appear in arid regions, in the 

lowest areas of basins, and contain great quantities of sediment. Rogers 

originally received its water from overflow of rivers in the Sierra Nevada 

to the northwest. In time, the water sources disappeared, the lake dried, 

and the arid Mojave now keeps it that way except for the briefest of 

periods when rain floods its surface to a depth of a few inches. 

The desert winds blow the water (and suspended sediment) back and 

forth across the lake surface, filling cracks and smoothing the silt. When 

the water evaporates, the lake is perfectly flat and smooth. Once dry, 

Rogers is also hard; the water and winds remove dissolved salts from the 

sediment, which dries to a hard crust-at Rogers, from 19 to 45 

centimeters deep. California has a great number of lakes like RogersRosamond, Mirage, Cuddeback, Harper, Searles, Koehn, China, Ballarat. 

Rogers, the largest dry lake in the world, is clearly visible to the traveler 

flying into Los Angeles from the east. In the early part of the 20th 

century, a silver and gold mining firm established a camp on its shores 

and named it Rodriguez, after the company’s name. Rodriguez eventually became Rogers. The lake, shaped like a lopsided figure eight, is dry 

for 10 months of each year. During that time its surface can support up 

to 1’760 kilograms per square centimeter (250 pounds per square inch) of 

pressure. Even the heaviest aircraft can take off from and land on the lake, 

making Rogers the largest landing field in the world. 

Aviation was a long time in coming to Rogers. At first the lake served 

only as a bed for the Santa Fe Railway and a small camp specializing in 

the extraction of drilling mud for use in oil wells. In 1910 came the first 

xiv 
a 

PROLOGUE 

permanent settlers, Clifford and Effie Corum, and Clifford’s brother 

Ralph. The Corums were determined to start a farm community in the 

midst of this wasteland; surprisingly, they convinced other settlers to join 

them. The brothers opened a general store, dug wells for water, and held 

church services in their home. The Santa Fe Railway’s freights always 

stopped for water. Encouraged, the Corums decided to name the little 

community after themselves. Here they ran into a snag. Postal authorities 

objected because California already had a Coram township; the similarity 

in spelling would surely cause confusion. The Corums then suggested 

Muroc, created by spelling the name backwards, but the Sante Fe Railway 

objected because of a rail stop named Murdock. The railroad lyrically 

suggested Dorado, Ophir, Yermo, or Istar. (It is puzzling how many truly 

desolate desert communities have names connoting beauty, tranquility, 

and prosperity.) The Corums remained firm. The tiny community 

became Muroc; settlers sometimes applied the name to the dry lake as well. 

Muroc did not prosper and remained little more than a spot on a 

map. The 1930s brought Depression and the Okies wending their way 

along Highway 58, north of the lake. The lake itself gained notoriety as 

the site of what was supposedly the largest moonshine distillery in 

southern California; at night, prohibition agents chased liquor runners 

across the lakebed. Other citizens used the lake to race automobiles. By 

1930, designers and pilots already recognized the value of the dry lakes as 

test sites for new aircraft, and Rogers, together with Harper and 

Rosamond, became a favorite spot for small aircraft companies to fly 

their new designs. Here aviatrix and socialite Florence “Pancho” Barnes 

established a dude ranch and nightclub with a small private airstrip; in 

future years, Barnes “Fly-Inn” became a popular gathering spot for test 

pilots and engineers. 

The military came to Muroc in 1933, at the behest of Col. Henry H, 

“Hap” Arnold, commanding officer of the Army’s March Field at 

Riverside, California. Arnold, later to become the Army Air Forces’ chief 

in World War 11, needed a desolate site for a bombing and gunnery 

range. The Navy having denied Arnold the use of the Pacific Ocean, he 

looked elsewhere. The most logical site for the range was the vast barren 

stretches of the Mojave; most of the land around Rogers Dry Lake 

already belonged to the federal government. In September 1933, a cadre 

of soldiers from March established a camp on the eastern side of the lake 

and laid out the gunnery and bombing range. Over the next decade the 

desert echoed to the snarling throb of brightly painted Boeing P-26A 

fighters, as well as Northrop A- 17 and Martin B- 10 bombers, as Army 

pilots bombed and shot up the desert. The tiny community of Muroc, on 

the west side of the lake, was not really affected. The community’s only 

xv 
ON THE FRONTIER 

live contact with the “Golden Age” of American aviation came in 1935, 

when Wiley Post force-landed his Winnie Mae on the lake. From the 1940s 

to the early 1950s, John Northrop’s ethereal flying wings were a familiar 

sight in Muroc skies. 

In the summer of 1941, when the Third Reich controlled the 

European continent and Japan was firming up plans for the Greater East 

Asian Co-Prosperity Sphere, 13 Army employees manned the bombing 

and gunnery range. Then on 10 July 140 troops arrived via the railway 

across the lakebed and staked out a tent camp on the southwestern shore 

of the lake. The character of operations at Muroc changed. What had 

been a useful bombing and gunnery site now also became a remote 

testing site. Here, in 1941, Maj. George V. Holloman experimented with 

radio-controlled Douglas BT - 2 basic trainers, a highly classified project 

with future implications for pilotless robot weapon development. 

On 7 December 1941 the Army’s 41st Bomb Group and the 6th 

Reconnaissance Squadron arrived at Muroc for crew training. That same 

day, Japanese naval aircraft devastated Pearl Harbor and America was at 

war. Two days later, four squadrons of Martin B-26 Marauders arrived 

at Muroc for coastal antisubmarine patrol duty, but left in February 1942 

for Australia and the bitter New Guinea campaign. The war brought a 

rapid influx of people, eventually numbering 40 000. The community of 

Muroc vanished, buried under a tent city erected on the site of what is 

now South Base. On 23 July the rapidly growing site was designated 

Muroc Army Air Base. On 8 November 1943 the Army redesignated it 

Muroc Army Air Field, complete with barracks, sewerage system, control 

tower, and year-round concrete runway. Engineers built a 200-meter 

replica of a Japanese Mogurni-class heavy cruiser on the lake-“Muroc 

Maru” the pilots dubbed her-and antishipping bomber crews honed 

their skills. Fighter pilots in P-38s and bomber crews in B-24s and 

B - 25s flew training missions at Muroc before going overseas. Yet Muroc 

did not remain simply an advanced training base, valuable as this would 

have been to the war effort; it also became a major research and 

development center. 

Before World War 11, the Army’s major aeronautical research and 

development center had been at Wright Field, outside Dayton, Ohio. But 

Wright was in a heavily residential area; hazardous flight testing of 

prototypes could endanger the local population. Also the area was too 

populous to be safe from prying eyes. Anyone could see the latest 

aircraft going through its paces, just by watching from beyond the 

airfield’s boundary. The Army needed a remote test site. Muroc, a mere 

160 kilometers from the center of the West Coast’s aircraft industry, was 

ideal. 

The catalyst that caused the big change from Wright to Muroc was 

the Bell XP-59A program, the United States’ first jet aircraft. In April 

xvi 
PROLOGUE 

1941, Hap Arnold had learned of Britian’s jet engine research while on 

an inspection trip to England. In September the Army issued a contract 

to the Bell Aircraft Corporation for a jet airplane using a Britishdeveloped Whittle engine built by General Electric. The result was the 

Bell XP- 59A Airacomet, a twin-jet single-seat airplane. Obviously, the 

XP-59A was too secret to test at Wright. Lt. Col. Benjamin W. Chidlaw, 

one of Arnold’s deputies, toured the country looking for a suitable test 

site. Without question, Muroc was the best possible choice. In 1942, the 

Materiel Center at Wright Field designated the northwestern end of the 

dry lake as the Materiel Center Flight Test Site. Subsequently, this site 

became known as North Base and the training center on the southwestern lake shore became known as South Base. Security, already tight, 

became viselike. The XP-59A arrived at North Base in mid-September 

1942 and made its initial flight on 1 October. The U.S. entered the jet 

age, third behind Germany and Great Britain. 

Soon the importance of Muroc as a flight test center overshadowed 

its importance as a training base. North Base conducted its operations 

strictly separate from South Base, and added its own runway, hangar, 

and tower facilities. The first tower was a guard shack mounted on two 

large sawhorses; sometimes it blew over in the desert winds. Known as 

“Oscar Junior,” it had a single Hallicrafter radio connected by a 1 1 0-volt 

extension cord to the operations building, a frame hut. A field telephone, 

binoculars, and salt tablets for the tower crew completed its equipment. 

“Oscar Senior,” a genuine aircraft control tower with a variety of 

communications equipment and clear glass sides, entered service in July 

1944. By that time, the P-59 was no longer queen of the flightline. 

Lockheed’s XP-80 Shooting Star, dubbed Lulu-Belle by Lockheed engineers, 

had completed its first flight at North Base in January 1944. That same 

year the Army redesignated North Base as the Muroc Flight Test Base, 

coequal with its training counterpart to the south. On 15 April 1946, with 

wartime needs buried in an already fading past, the Army Air Forces 

ended all training activities at Muroc, designating Muroc solely as a 

research and development center under the name Muroc Army Air 

Field. This lasted until 12 February 1948, when it became Muroc Air 

Force Base following the establishment of the United States Air Force. 

On 8 December 1949 it was renamed Edwards Air Force Base in honor 

of Capt. Glen W. Edwards, killed in the crash of a Northrop YB-49 

Flying Wing on 5 June 1948. 

Muroc-Edwards after World War I1 remained an important research center. The war had pointed to the importance of such new 

developments as jet aircraft, and the tempo of wartime research had 

generated new conceptions of aircraft design-such as the swept-wing 

planform-that might prove useful on future military and civil aircraft. 

The rapid disintegration of the wartime Grand Alliance, underscored by 

xvii 
t c I 

ON THE FRONTIER 

the lowering of the “Iron Curtain” in Central and Eastern Europe, acted 

as a spur to continued rapid research on projects that might ultimately 

affect national security. Captured enemy aircraft such as the Heinkel He 

162 flew at Muroc in evaluation programs. Work continued on radiocontrolled aircraft-two B - 17s flew from Hawaii to Muroc under radio 

guidance in 1946. Weird combination jet-and-piston aircraft such as the 

Convair XP-81 and Ryan XF2R- 1 flew from the lake, as did new 

bombers such as Douglas’s XB -42 and Northrop’s graceful though 

ill-fated XB-35 and YB-49 Flying Wings. But the big news in the fall of 

1946 was not the testing of some new aircraft destined for squadron 

service nor the latest scoop on what the Germans or the Japanese had 

been up to in the war. Rather it was anticipation of a program of such 

significance that the whole fabric of aviation might be transformed. 

The program revolved around a technological challenge: Could 

aeronautical science design an aircraft that could fly faster than the speed 

of sound? Today, what with manned spaceflight and mach 2 commercial 

airline service, such a question seems almost trivial. In 1946, however, 

that question loomed across the face of aeronautics; highly trained 

engineers spoke of a mysterious “sound barrier” through which it might 

be impossible to fly a manned aircraft. The challenge was not simply a 

theoretical one that threatened the imagination of designers hunched 

over drawing boards. Pilots had died as their aircraft approached the 

speed of sound, died when their aircraft broke up in high-speed dives. 

The “sound barrier” threatened to deny aeronautical science the high 

speeds that the jet engine promised, to limit aviation to speeds of about 

950 kilometers per hour. 

In September 1946, the National Advisory Committee for Aeronautics (NACA), the aeronautical research agency for the United States, sent 

a small band of engineers and technicians from the Langley Memorial 

Aeronautical Laboratory at Hampton, Virginia, to Muroc to assist in a 

supersonic flight research program involving the Bell XS- 1 aircraft. 

This small group became known as the NACA Muroc Flight Test Unit a 

year later. In October 1947 the XS-1 exceeded the speed of sound in 

level flight, the first manned supersonic flight. For the next decade, the 

NACA group continued to explore the problems and conditions of 

supersonic flight. In 1949, the NACA had established the group as the 

NACA High-speed Flight Research Station (HSFRS), a division of 

Langley Laboratory. In 1953, an HSFRS pilot became the first to fly at 

twice the speed of sound. In 1954, the HSFRS was redesignated the 

NACA High-speed Flight Station (HSFS), autonomous from Langley. 

That summer, the station’s 250 employees moved from their shared Air 

Force quarters to new research facilities located midway between South 

Base and North Base. Those facilities are still in use. 

xviii 
PROLOGUE 

In 1959, after the creation of the National Aeronautics and Space 

Administration, the High-speed Flight Station became the NASA Flight 

Research Center (FRC). The following decade saw the center embark on 

a strong program of hypersonic research using the North American 

X- 15 aircraft. The X- 15, launched over Utah toward Edwards, could 

streak to mach &six times the speed of sound-over the Nevada and 

California desert. FRC personnel complemented the X- 15 program 

with a flight test program using lifting body reentry vehicles and with 

studies in several space and aeronautics areas. The later 1960s saw a 

resurgence of interest in advanced supersonic research using such 

aircraft as the triple-sonic XB-70A and YF-12 Blackbird. In the 1970s 

the center continued with its lifting body research in support of the Space 

Shuttle program, YF- 12 program, and such development programs as 

the F- 8 Digital Fly-by-Wire and supercritical-wing programs. 

On 26 March 1976, NASA renamed the Flight Research Center the 

Hugh L. Dryden Flight Research Center (DFRC), in honor of an 

American aerospace pioneer, a man who was fond of saying “the airplane 

and I grew up together,” and who once remarked that “the most 

important tool in aeronautical research. . . is the human mind.” Not a 

center to remain looking to its past, Dryden looks to the future; less than 

a year after the Dryden dedication, DFRC undertook the first flight tests 

of the Rockwell Space Shuttle orbiter Enterprzse. Five years after dedication, 

the Space Shuttle Columbia landed at the center, having completed the 

first winged reentry of a manned spacecraft from orbit. 

Many decry the cost of flight testing, the cost in both economic and 

human terms. They argue for computer simulation and prediction, a 

turning away from manned vehicle testing, a turning away from actually 

building an aircraft and flying it. There is no better refutation to the 

hypothesis that flight research is unnecessary than the testimony of 

NASA Administrator James E. Webb before Congress in 1967. 

Flight testing of new concepts, designs, and systems is fundamental to 

aeronautics. Laboratory data alone, and theories based on these data, cannot 

give all the answers. . . . Each time a new aircraft flies, a “moment of truth” 

arrives for the designer as he discovers whether a group of individually satisfactory elements add together to make a satisfactory whole, or whether their 

unexpected interactions result in a major deficiency. Flight research plays the 

essential role in assuring that all the elements of an aircraft can be integrated 

into a satisfactory system. 

At Dryden, flight research is not simply one phase of the center’s 

operation. Rather, it is the center’s reason for being. 

xix 
h c 
Exploring the Supersonic Frontier: 

1944- 1959 
d 
w 

1 

Confronting the Speed of Sound: 

1944- 1948 

Since its creation, the NASA Hugh L. Dryden Flight Research 

Center has made two major contributions to aviation. The first and 

most important was its contribution to the early development of supersonic flight technology. The second was its research on the problems of 

flight out of the atmosphere, including lifting reentry during the return 

from orbit. Unlike other NASA research centers, Dryden relies almost 

exclusively on a relatively new kind of research tool-the research 

airplane, which uses the sky itself for a laboratory. Thus its research in 

these two major areas, and many minor ones as well, is bound up in the 

development and testing of a wide range of specialized jet and rocketpropelled research aircraft. Some of these exotic vehicles, such as the 

X- I, X- 15, and the Space Shuttle, have become well known in their 

own right, but they all play an integral part in the history of the Dryden 

center. The history of Dryden-in many ways a microcosm of the history 

of post-World War I1 flight research-thus falls conveniently into two 

chronological phases: the era of the supersonic breakthrough, 1944- 1959; 

and the heroic era of manned spaceflight, 1959- 1981. Symbolically, the 

landing of the Space Shuttle Columbia on the baked clay of Rogers Dry 

Lake in 1981 brought this first phase of manned spaceflight to a close 

while reaffirming the importance of the role that Dryden plays in the 

development of advanced technology for winged vehicles. 

ORIGINS 

The origins of the Dryden center, “DRFC” as it is known to the world 

aeronautical community, are inseparable from the story of the postwar 

assault upon the speed of sound, the infamous and highly touted “sound 

barrier.” By the late 1950s, supersonic flight-flight faster than soundhad become so commonplace that pilots of supersonic planes gave little 

3 
ON THE FRONTIER 

thought to the cockpit machmeter when its pointer moved above mach 1, 

the speed of sound.” Yet a mere decade before, supersonic flight had 

been a distinct novelty; and two decades before, leading aerodynamicists 

around the world had debated with great intensity whether supersonic 

flight was, indeed, possible. 

During the 1920s and 1930s, aviation technology had advanced 

rapidly. In this period, powerful piston engines had been developed. 

Advances in structural design and a growing appreciation of the need for 

streamlining an aircraft for high-speed flight enabled creation of highspeed military aircraft by the end of the 1930s that could approach 

transonic speeds. (The transonic region refers to that area between mach 

0.7 and mach 1.3 where a plane encounters mixed subsonic and 

supersonic airflow.) Many aircraft had highly undesirable behavior characteristics as they approached high speeds during prolonged dives. The 

airflow over the wings accelerated, shockwaves would form, causing the 

smooth flow of air around the aircraft to be disturbed and end in a 

swirling wake of turbulent flow that flailed at the tail section, sometimes 

inducing structural loads so severe that the tail would be ripped from the 

craft. Because of the inadequacy of high-speed wind tunnel design-a 

shortcoming only overcome by the postwar development by NACA of the 

so-called “slotted-throat” wind tunnel-the problems of transonic flight, 

such as compressibility, increased drag and undesirable trim changes, 

loss of lift, and the onset of “standing” shockwaves could not be 

adequately examined. Many short-cut research solutions were tried, 

including dropping weighted body shapes from high-flying aircraft and 

then tracking their descent with radar, firing small rocket-propelled 

models, and (most useful but also most dangerous) placing small test 

models on the wing of a modified fighter and then diving the fighter to 

more than mach 0.7, when the accelerated flow over the wing would be 

above mach 1. Pending the development of reliable wind tunnel research 

methods, however, the best solution seemed to be a new class of research 

tool: piloted research airplanes powered by jet or rocket engines and 

capable of attaining high speeds in the relative safety of high altitude, 

rather than racing toward Earth in dangerous dives into the dense lower 

atmosphere where a plane experiences its greatest structural loadings. 

The story of supersonic research has not received much attention from 

historians, though accounts of NACA research work, the development of 

specific research airplanes, and foreign work in this field do exist.’ 

*The speed of sound varies with altitude, dropping from approximately 340 meters per second 

at sea level to 295 meters per second at altitudes between 11 000 and 20 000 meters. Mach number 

(after the Austrian physicist Ernst Mach) is the ratio of the speed of an object to the speed of sound. 

4 
i h 

The Lockheed P- 38 Lightning, an early victim of compressibility. Official US. Army Air 

Corps. 

A wing-flow research model is mounted on the wing of the NACA-Langley North American 

P-51D Mustang. 

5 
ON THE FRONTIER 

The establishment of the first research aircraft programs led directly 

to the creation of the Dryden center. The advocates of supersonic 

research aircraft-notably John Stack of NACA, Ezra Kotcher of the 

Army Air Forces, and Walter Diehl of the Navy-did not realize at first 

that a special test facility for these aircraft would have to be created. 

Kotcher and Diehl assumed that the planes would probably pass through 

the standard service test centers-Muroc and the Naval Air Test Center 

at Patuxent River, Maryland. Most NACA personnel simply assumed that 

the planes would fly from the NACA’s major (and oldest) research 

laboratory, the Langley Memorial Aeronautical Laboratory at Hampton, 

Virginia. Several factors worked to change this. First, the NACA did not 

have the resources to undertake development of such craft on its own; 

they had to be sponsored by the military services and manufactured by 

private industry. Second, the aircraft developed had (for their day) 

hazardous or at least unusual flying characteristics. Some were airlaunched from larger airplanes. Others had strange configurations that 

demanded plenty of room for takeoff and landing. Third, the natural 

location for such testing-a situation offering isolation far away from 

prying eyes, unparalleled year-round flying conditions, and proximity to 

that hub of the American aircraft industry, the Los Angeles basin-was 

Muroc, where the AAF had already established its wartime center for advanced aircraft testing. 

Two research aircraft programs had begun in 1945: the rocketpropelled and Air Force-sponsored Bell XS- 1 and the jet-propelled and 

Navy-sponsored Douglas D-558. The latter program eventually split 

into a straight-wing D-558- 1 (the Skystreak) and a sweptwing jet-androcket propelled D-558-2 (the Skyrocket). Of the two, the D-558 came 

closest to meeting what NACA research airplane advocates-especially 

Stack-had envisioned, primarily because of its turbojet engine, which 

enabled the craft to cruise at speeds above mach 0.8 for over half an 

hour. The XS-1 (later designated X-1) represented a more radical 

approach, for at its conception in early 1945 liquid rocket propulsion was 

regarded-rightly-as unproved, dangerous, and unreliable. Yet the 

XS- 1’s rocket engine certainly endowed the craft with much higher 

potential performance than the contemporary D- 558. And the Bell 

aircraft was also the first of these new research airplanes (which subsequently became known as the postwar “X-series”) to be completed. It 

rolled out of the Bell plant at Buffalo, New York, late in December 

1945. 

Within a year of the development of the XS-1 and D-558 series, 

however, the Army Air Forces and the NACA began collaborative 

development of four other research aircraft, adding two more within 

another three years. All of these were aerodynamic testbeds of one sort 

6 
THE SPEED OF SOUND 

or another, or designed to explore the potential benefits or difficulties of 

some new design configuration. Table 1 permits comparison of these 

craft, which constituted the nation’s “stable” of transonic and supersonic 

research aircraft for flight testing at speeds up to mach 3. Only one, the 

XF-92A, bore any relationship to a planned military weapon system (the 

abortive XP-92 interceptor), though the XF- 92A was solely intended 

for the delta-wing research role it subsequently fulfilled. The Bell X-5 

derived from a wartime German research project, the Messerschmitt P 

1 10 1, using a generally similar configuration, though its provision for 

variable in-flight wing sweeping was uniquely American. The X-4 was 

greatly influenced by some wartime German research, the contemporary 

British De Havilland D.H. 108 Swallow, and Northrop’s own interest in 

the tailless or semitailless wing configuration. The Dryden center subsequently flew examples of all of these aircraft during 1947- 1958, with the 

exception of the ill-fated Bell X-2. The research programs conducted 

on these aircraft will be discussed later. 

THE ROAD TO MUROC 

In December 1945, the same month that Bell completed the first 

XS- 1, the AAF asked NACA to supervise all details of the XS- 1’s data 

gathering and analysis program. The request was a logical one, since the 

NACA Langley instrumentation staff had drawn up the instrument 

requirements for the craft, and it meant that the NACA would have to 

follow wherever the plane went to fly. The Air Technical Service 

Command opted to fly the XS-1 first as a glider, air-launched from a 

modified Boeing B - 29A Superfortress, at Pinecastle Field, Orlando, 

Florida. The Pinecastle trials would enable researchers to assess the 

craft’s low-speed behavior and general handling qualities in much the 

same way that the Space Shuttle Enterprise first flew as a glider at Dryden 

over 30 years later. Langley Laboratory Director H. J. E. Reid informed 

NACA Headquarters that the Pinecastle tests would determine if the 

XS- 1 could operate from Langley. In fact, the chief of the Air Technical 

Service Command, Maj. Gen. Franklin 0. Carroll, had decided to fly the 

craft from Muroc, where the AAF had tested its first jet airplanes. Thus 

even before the XS-1 first flew, it was evident that the NACA would 

have to establish a team to accompany the craft, first to Pinecastle and 

then to Muroc. 

And so it fell to the Langley flight test branch to select a small team 

under the direction of an engineer to assist the military on the XS-1 

trials. Hartley A. SoulC, chief of Langley’s Stability Research Division, 

together with chief NACA test pilot Me1 Gough and research airplane 

advocate John Stack, selected a young but highly experienced engineer for 

7 
P 

ON THE FRONTIER 

oo&o 

-mmo 

sn 

nnm 2 

9 

8 
THE SPEED OF SOUND 

the job: Walter C. Williams. Williams had worked in Soulc‘s stability and 

control branch at Langley, was one of NACA’s foremost research 

airplane advocates, and had a good background in flight testing of 

high-performance aircraft. A New Orleans native, he was an inquisitive, 

take-charge sort of engineer, a man who believed that useful research 

had to confront actual problems and not be limited to studying theoretical aspects of aeronautical science. He had a painstaking obsession with 

planning and safety. Reflecting two decades later on his role in flight 

research, Williams summarized his beliefs by stating: “I never bought the 

philosophy this is a dangerous business, we’re going to kill people. I 

always felt by careful preparation, careful planning in carrying the flight 

out in a careful manner, you can do some pretty exotic things, like orbiting 

a man or breaking the sound barrier, without killing people.” * 

With five technicians, Williams journeyed to Pinecastle early in 

January 1945. The NACA unit used a modified SCR-584 gun-laying 

radar equipped with a camera to provide accurate flight path data. The 

orange XS- 1 completed its first glide flight on 19 January 1946, piloted 

by Bell test pilot Jack Woolams. This and the remaining flights generally 

went smoothly, but the plane’s high sink rate and the problems of 

keeping the plane in sight amid Florida’s frequent clouds added two 

more votes in favor of the AAF‘s decision to go to Muroc. In March 1946, 

the XS- 1 went back to Bell for installation of its four-chamber Reaction 

Motors XLR-11 rocket engine. Over the summer of 1946, NACA 

Langley prepared to send a larger test support team to Muroc under 

Williams’s direction. On 30 September Williams and four other engineers 

(William S. Aiken, Cloyce E. Matheny, George P. Minalga, and Harold H. 

Youngblood) arrived at the desert site. They proceeded to set up an 

SCR-984 radar tracking system. A second group of six (Joel Baker, 

Charles M. Forsyth, Beverly P. Brown, John J. Gardner, Warren A. 

Walls, and Howard Hinman) flew out from Langley, arriving on 9 

October. Subsequently this original group would be completed in December with the arrival of two “computers,” Roxanah B. Yancey and Isabel1 

K. Martin.5 NACA had arrived at Muroc in force. 

The team, not surprisingly, was composed primarily of engineers, 

instrument technicians, telemetry technicians, and computers. Since 

the 192Os, NACA had instrumented flight research airplanes to record 

various kinds of data, but telemetry was a relatively new field. Telemetry 

involved onboard instrumentation that would measure certain quantities, 

a transmitter to send a signal from the plane to a ground station, and a 

receiver to pick up the signal. Active data transmission (“telemetering”) 

had come into its own with the opening of the Panama Canal, which 

relied extensively on telemetry systems to report on the operation of the 

canal and its physical environment. Aircraft, missile, and ordnance 

9 
ON THE FRONTIER 

NACAs 1946 Pinecastle test team at Orlando, Florida, including from left to right) 

Gerald Truszynski, John B. Householder, Walter C. Williams, Norman Hayes, and Robert 

Baker. 

telemetry development and systems had proliferated during World 

War IL6 The XS- 1, at NACA’s direction, had a 6-channel telemetry installation to transmit airspeed, control surface position, altitude, and 

normal acceleration to the ground so that, as Walter Williams later 

explained, “if we lost the airplane, we could at least find out a little about 

what had happened.”’ 

In contrast to the telemetry technicians, “computers” were an older 

institution of the Federal government’s scientific establishment. In NACA 

terminology of 1946, computers were employees who performed laborious and time-consuming mathematical calculations and data reduction 

from long strips of instrumentation records generated by onboard 

aircraft instrumentation. Virtually without exception, computers were 

female; at least part of the rationale seems to have been the notion that 

the work was long and tedious, and men were not thought to have the 

patience to do it. Though equipment changed over the years and most 

computers eventually found themselves programming and operating 

10 
r 

THE SPEED OF SOUND 

electronic computers, as well as doing other data processing tasks, being a 

computer initially meant long hours with a slide rule, hunched over 

illuminated light boxes measuring line traces from grainy and obscure 

strips of oscillograph film. Computers suffered terrible eyestrain, and 

those who didn’t begin by wearing glasses did so after a few years.8 

The N ACA group quickly-but uncomfortably-settled themselves. 

Walt Williams took an apartment in Palmdale, over 65 kilometers distant. 

Single engineers and mechanics lived in “Kerosene Flats,” a collection of 

kerosene-heated fire-trap Air Force quarters at the town of Muroc, 

shared with visiting military personnel. Late in 1946, when the Navy 

Department closed down the Marine air station in the town of Mojave, 

housing there became available to married N ACA personnel. Adding to 

the unhappy conditions was the attitude of certain senior AAF base 

administrators at Muroc, who tended to regard the NACA contingent as 

visiting contractors, rather than partners on a top-level government 

project. The increasingly acute housing problem and work space situation (NACA at first had only two small rooms and shared hangar space 

with the AAF) came to a head in early 1948, triggering action by the 

NACA headquarters to improve the lot of the Langley ~ontingent.~ 

In early October 1946, the second Bell XS-1, the first destined to 

make a powered flight, arrived at Muroc. In preparation for its testing, 

Army technicians had installed two large liquid-oxygen and liquidnitrogen tanks in the fueling area (the nitrogen was used to pressurize 

the XS- 1’s fuel system, for the plane burned liquid oxygen and diluted 

alcohol) and dug a large loading pit from which the XS-1 could be 

hoisted into the bomb bay of a modified B-29. They also modified a 

standard Army fuel trailer to function as a mixing tank for the XS- 1’s 

diluted alcohol fuel. The Bell test team, headed by project manager Dick 

Frost and including project test pilot Chalmers “Slick” Goodlin-the 

previous Bell pilot, Jack Woolams, having been killed in the crash of a 

racing plane-was ready to fly. Walt Williams’s NACA team had its equip- ment set up, including two SCR-584 radars. The technical people on the 

lakebed set about to make their mark upon aeronautical science.” 

PLANNING THE ASSAULT 

With the benefit of hindsight, it is easy to be puzzled at all the fuss 

about transonic flight and the “sound barrier” myth. It is not easy to 

appreciate just how dangerous the sound barrier seemed to be. By the 

fall of 1946, most AAF, Bell, and NACA personnel believed that the 

XS- 1 would probably exceed the speed of sound safely, but they could 

not deny the possibility that it might not. The first group of NACA 

personnel left Langley just after Geoffrey de Havilland died in Great 

11 
P * c 

ON THE FRONTIER 

Britain. De Havilland, one of Britain’s finest test pilots, had been killed 

on 27 September 1946 when the tiny De Havilland D.H. 108 Swallow, a 

tailless aircraft resembling the later American X-4, began violent 

pitching during a dive to mach 0.875 while flying at less than 2400 meters 

over the Thames estuary. The D.H. 108 had broken up from the severe 

airloads at lower altitudes, killing the 36-year-old pilot instantly. The 

accident further reenforced the belief of NACA researchers that all such 

testing should be undertaken at higher altitudes where the dynamic 

forces acting on an airplane were less severe. 

On 11 October 1946, the XS- 1 dropped from its launch aircraft on 

a seven-minute glide flight, ushering in the era of the rocket-powered 

research airplane at Muroc. By early December, the craft was ready for 

powered flights, and on the ninth Slick Goodlin reached mach 0.79 at 

11 000 meters, still within the scope of contemporary aerodynamic 

knowledge. Under the terms of the development contract, Bell had to 

demonstrate that the craft had satisfactory flying qualities up to mach 

0.8; beyond this, the company could not be held responsible for any 

quirks the plane might exhibit as it approached the speed of sound. By 

the end of May, both the first and second XS- Is had adequately met the 

demonstration requirements, having completed 20 powered flights without an accident. The third XS- 1 was still at Buffalo awaiting a decision 

from the Air Force on what kind of a fuel feed system to incorporate in it. 

Bell had assumed that when the time came for the actual assault on 

mach 1, the company would be called upon to fulfill the mission, using its 

own test pilots. In fact, however, the AAF and NACA had already 

decided otherwise. The NACA was to get one XS- 1 for its own testing. 

At NACA headquarters in Washington 6 February 1947, Colonels J. 

Stanley Holtoner and George Smith, with Gus Crowley, NACA acting 

A ground engine test of the second Bell X S - 1 during the Bell contractor program at 

Muroc. 

12 
THE SPEED OF SOUND 

director of research, and Hartley A. SoulC, the de facto chief of NACA’s 

research aircraft program, hammered out a joint agreement for the 

conduct of all research aircraft projects, XS- 1 through XS-4. The 

NACA would furnish its own maintenance and flight crews, as would the 

AAF. ,The AAF would also supply spare parts. To eliminate wasteful 

duplication, the AAF would offer to the NACA any available services 

over which it had control at an AAF base, and the Air Materiel Command 

(which had replaced the earlier Air Technical Service Command) would 

provide office space, shelter, housing, and equipment. In recognition of 

the importance of the growing X-series program, the AAF agreed to 

assign research airplanes a “I - b” priority, higher than that of tactical 

aircraft. For its part, the NACA affirmed that it had already placed 

research airplanes “in the highest priority class of NACA programs.” The 

meeting attendees also agreed that the NACA would “enter research 

aircraft ro ects at their initiation, in any case before configurations are 

fixed.”’PMianwhile, back at Muroc, DeElroy E. Beeler had joined the 

Muroc unit from Langley to supervise the XS- 1 loads research program, 

and in March 1947 Gerald M. Truszynski became project instrumentation engineer. Joseph Vensel, a former NACA Langley test pilot, arrived 

in April to supervise NACA flight operations. Three months later, the 

first two NACA pilots arrived for duty at Muroc, Herbert H. Hoover of 

Langley and Howard C. “Tick” Lilly from Lewis Laboratory.12 

On 30 June 1947 NACA and Air Materiel Command (AMC) 

conferees met at Wright Field, Ohio, to discuss the conduct of the XS- 1 

research program. They agreed to a two-phase program. Using the first 

XS- 1, which had a thin (8% thicknesdchord ratio) wing planform, the 

AMC’s Flight Test Division would conduct an accelerated test program, 

with NACA support, to reach mach 1.1 as quickly as was prudent. 

NACA’s Muroc team would conduct slower and more detailed research, 

making thorough examina ns of stability and control and flight loads at 

transonic speeds using e second XS-1 with its thicker (10% 

thicknesdchord ratio) wing planform. Bell was out of the supersonic 

running, though the AMC decided to borrow Dick Frost to run a ground 

school for the AMC test team.13 Col. Albert Boyd, a highly respected test 

pilot who directed AMC’s Flight Test Division, selected Capt. Charles E. 

“Chuck” Yeager as project pilot, assisted by Capt. Jack L. Ridley as flight 

test engineer and Lt. Robert Hoover as chase and alternate pilot. Yeager, 

a 24-year-old fighter ace from Hamlin, West Virginia, was a superlative 

pilot and an intuitive engineer. 

On 6 August 1947 the two-pronged Air Force-NACA program got 

under way with a familiarization glide flight by Yeager in the Air Force 

XS- 1. The take-charge ways of the Air Force jarred the NACA pilots, 

who were used to the staid and sedate ways of Langley and Lewis. Herb 

13 
a a 

ON THE FRONTIER 

Hoover wrote to Me1 Gough at Langley that “this guy Yeager is pretty 

much of a wild one, but believe he’ll be good on the Army ship. . . On 

first drop, he did a couple of rolls right after leaving B-29! On third 

flight, he did a 2-turn spin!” Admiration mixed with shock. But Hoover 

also informed Gough what he thought of Walt Williams. “Williams is 

doing and has done a fine job,” Hoover wrote. “He doesn’t lose sight of 

the fact that a job has to be done.”14 By the end of August, Yeager had 

completed his first powered flight, reaching mach 0.85. With Chuck 

Yeager now fully checked out in the plane, the Air Force and NACA 

could turn to the series of flights that would, they hoped, take the XS- 1 

through the speed of sound. 

It had become clear that the NACA contingent would be at Muroc 

for a long, long time. Hugh Latimer Dryden, an internationally known 

aeronautical scientist, had become the NACA’s director of research on 2 

September 1947. Among his first actions was a directive informing Walt 

Williams on 7 September that henceforth the NACA Muroc unit would 

function as a permanent facility, managed by Langley Laboratory. The 

group, now 27 strong, would be known as the NACA Muroc Flight Test 

Unit and would report to Soul6 at Langley. Before the end of the month, 

Dryden and his deputy, Gus Crowley, visited Muroc, where the director 

of research reaffirmed the agency’s top priority support of transonic 

flight research. The NACA Muroc outpost was but the most recent of a 

series of laboratories and research facilities that Langley had spun off. 

There had been Ames in California, then the propulsion laboratory at 

Cleveland, the small Pilotless Aircraft Research Division at Wallops 

Island, and now the Muroc unit. Langley and its sibling Ames had always 

been friendly rivals. The Navy’s Walter Diehl, for example, used to play 

John Stack and H. Julian Allen off against one another to get things 

done, by going to Langley and goading Stack with the latest news about 

what Allen was doing, and vice versa. Langley engineers unconsciously 

wanted to show that the parent was still ahead, while Ames engineers 

smarted under perceived paternalism. Ames’s director, Smith J. De 

France, suspiciously eyed this Langley offshoot growing in his backyard, 

but remained content to watch what was going on, occasionally sending 

observers to Muroc to monitor the work of the Langley group on the 

XS- 1. l5 One senior NACA Muroc engineer remembers his first meeting 

with the strong-willed De France: “Well,” boomed Smitty, “when are you 

going to blow up the plane, kill the pilot, and go De France later 

proved very helpful to Williams’s band in the desert. And De France was 

no stranger to flight research or to its hazards; one of NACA’s earliest 

flight researchers, he had been seriously injured in an aircraft accident at 

Langley that ended his flying career: 

14 
6 I ii a I 

THE SPEED OF SOUND 

THROUGH THE “SOUND BARRIER” 

On the tenth anniversary of the first supersonic flight by a piloted 

airplane, Walt Williams recollected that as the XS-1 had edged closer 

and closer to the magic mach 1 mark on a series of flights, NACA’s 

engineering staff at Muroc “developed a very lonely feeling as we began 

to run out of data.”” The last reliable wind-tunnel data ended at about 

mach 0.85; the last useful information from P-5 1 “wing-flow” dive tests 

ended at about mach 0.93. By early October 1947, Chuck Yeager was 

edging past that, nibbling at the “sonic wall” in the Air Force XS- 1, 

which he had named Glamorous Glennis, after his wife. During his flights 

Yeager worked closely with the NACA engineers, especially Williams.* 

With each succeeding flight to an incrementally higher mach number, 

NACA technicians would analyze the telemetry records, pull the onboard 

instrumentation records (lengths of scratchy oscillograph “traces,,), and 

study the results. Then they would meet with Williams and his chief 

assistant, De Beeler, and these two would present the results to the Air 

Force’s Yeager and Jack Ridley. The long strips of oscillograph records 

showed if the plane was losing control effectiveness, if more stabilizer 

trim was needed, if lateral (roll), longitudinal (pitch), or directional (yaw) 

stability was deteriorating. 

Early in October, Yeager reached mach 0.94 and had a nasty 

surprise-he pulled back on the control column and nothing happened. 

The plane continued to fly as if he hadn’t touched the controls. Wisely he 

shut down the rocket engine; as the plane decelerated, control effectiveness returned to normal. Williams’s engineers later determined that a 

shock wave had formed on the horizontal stabilizer; as the XS- 1 increased 

its speed, the shock wave had moved rearward, “standing” right along the 

hinge line of the plane’s elevator surfaces (which control pitch) at mach 

0.94, negating their effectiveness. Fortunately the XS- 1 had been 

designed with an adjustable stabilizer, so the NACA-Air Force team 

decided to control the craft with the conventional elevator up to where it 

lost its effectiveness, then use the stabilizer “trimmer” for longitudinal 

(pitch) control as the XS- 1 approached the speed of sound.” 

On 10 October Yeager again reached an indicated mach 0.94. 

During the glide earthwards, frost formed on the inside of the canopy, 

and despite persistent efforts Yeager could not scrape it off. Chase pilots 

Bob Hoover and Dick Frost, flying Lockheed P-80 Shooting Stars, had 

*On the wail of Walter Williams’s office in NASA Headquarters later was a photograph of the 

XS-I in flight with the inscription “To Walt: The mainspring that made it all possible-chuck 

Yeager, Major, USAF.” 

15 
t 

ON THE FRONTIER 

to “talk” him down to a blind landing on the lakebed. Gerald Truszynski’s 

technicians removed the oscillograph film and started their analysis, 

working long into the night. Engineers Hal Goodman and John Mayer 

compared the data from ground radar tracking with the airplane’s 

internal instrumentation, so tht errors in the cockpit machmeter, induced 

by airflow changes around the airplane as it approached the speed of 

sound, could be compensated for. That night, Goodman and Mayer discovered that instead of mach 0.94, all indications were that the XS- 1 had 

actually reached mach 0.997 at 12 000 meters; this worked out to approximately 1059 kilometers per hour, infinitesimally close to the speed of 

sound. Williams had the results by morning and passed them along to the 

Bell representative, Dick Frost. Both men recognized that all that they 

still needed was a clear-cut case; Williams feared that if too much publicity 

from the 10 October flight generated overconfidence, the Air Force might 

storm ahead and wind up losing the aircraft and pilot, with disastrous 

results for the research aircraft program. Besides, listeners on the ground 

had not heard the tell-tale sonic “boom” caused by a plane exceeding the 

speed of sound, a phenomenon already known to aviation science as a 

result of German experience with the supersonic V-2 missile. So Williams, 

De Beeler, and other NACA engineers, after telling Yeager and Ridley of 

the revised results, emphasized the need for a cautious approach to a 

clear-cut case of supersonic flight. Yeager’s enthusiastic reaction surprised no one; “He was really eager to get out there and bust it [mach 11,” 

Mayer later recollected. 

Supersonic flight was achieved 14 October. Preparations for the 

flight began as the sun peeked over the eastern shore of the lake, bathing 

the desert in a soft orange glow, complementing the saffron XS-1 

surrounded by technicians. There was one well-kept secret from all those 

present except Jack Ridley and Walt Williams-Yeager had two broken 

ribs, courtesy of a horse that had thrown him over the weekend. Stoically, 

Yeager had had the ribs taped by a civilian doctor to avoid being grounded 

by a military one. He confided to Ridley and Williams, however, and 

Ridley had cut the pilot a short length of broom handle to help him lock 

the plane’s entrance hatch in place! The B-29 launch crew knew of the 

fall but not of the broken ribs, and they presented him with glasses, a 

rope, and a carrot. That morning, after preflighting the aircraft, Yeager 

met with Williams and Beeler; they stressed caution, warning the young 

test pilot not to exceed an indicated mach number of 0.96 unless 

absoiutely certain, from the behavior of the plane, that he could do so 

safelv.20 

Technicians winched and locked the Glamorous Glennis snugly into 

the bomb bay of its B-29, then filled its tanks with 1177 liters of 

supercold liquid oxygen and 1109 liters of diluted ethyl alcohol fuel. At 

16 
P 

THE SPEED OF SOUND 

Yeager’s suggestion, crew chief Jack Russell rubbed the rocket plane’s 

windshield with Drene shampoo, an old fighter pilot’s trick to prevent 

frost from forming on a canopy at high altitude. Finally, all was ready. 

The NACA team was standing by the telemetry gear and twin SCR-584 

radars. The launch crew and test pilot entered the silver and black B-29, 

and soon its four engines were clattering noisily. At two minutes past ten 

o’clock, the Superfortress taxied away from its hardstand, the orange 

XS - 1 clasped tightly underneath, received takeoff clearance, and roared 

down the runway to the east. At 1500 meters, Yeager squirmed through 

the tiny entrance hatch of the XS- 1 , in acute pain from his broken ribs. 

As the B-29 continued to climb, Yeager readied Glamorous Glennis for 

flight. Two P-80 chase planes accompanied the B-29, one escorting the 

bomber to observe the launch, and the other about 16 kilometers ahead 

of the B-29 to join the XS-1 after it completed its rocket-propelled 

excursion through mach 1. A minute before launch, Jack Ridley raised 

Chuck Yeager on the intercom and asked, “You all set?” “Hell, yes, let’s 

get it over with,” Yeager replied. At 10:26 a.m., at a pressure altitude of 

6000 meters, Glamorous Glennis was launched into the skies over the Mojave 

Desert.*’ 

As the XS-1 dropped earthwards, Yeager briefly checked rocket 

engine operation by firing the four chambers of the XLR- 11 engine, 

shutting down two and climbing away to altitude on the remaining two, 

Key members of the X S - 1 test team (14t to right): Joseph Vensel, Gerald Trmszynski, 

Captain Charles “Chuck” Yeager, Walter Williams, MajorJack Ridley, and De E. Beeler. 

17 
i 

ON THE FRONTIER 

pulling away from one P-80. He fired the other two chambers and 

under a full 26 800 newtons (6000 pounds) of thrust, accelerated for 

altitude, the XS-1 streaming a cone of fire with bright yellow shock 

diamonds outlined in the exhausts from the rocket chambers. Further 

behind, a broad white contrail formed a long spearpoint with the little 

research airplane at its apex. Second by second the XS-1 was growing 

lighter, its engine gulping propellants, and the thrust-to-weight ratio rose 

higher and higher. The plane passed mach 0.8 and streaked on to mach 

0.9. Above mach 0.93, the adjustable stabilizer provided adequate 

longitudinal (pitch) control. He shut down two chambers briefly while 

he assessed his situation. 

All the signs were good; confident that Glamorous Glennis could safely 

exceed mach 1, Yeager leveled off and fired one of the two shut-down 

cylinders. Now very light from the amount of propellants that had 

already been consumed, the XS-1 shot ahead. At about mach 0.98 

indicated, the needle on the machmeter fluctuated, then jumped off the 

scale, leading Yeager to believe the plane was flying at about mach 1.05. 

In fact, postflight data analysis indicated the XS-1 had reached mach 

1.06 at approximately 13 100 meters, an airspeed of 1125 kilometers per 

hour. The machmeter jump - a hallmark of supersonic flight since - 

registered the passage of the bow shockwave across the nose as the plane 

went supersonic. And on the ground, observers heard the characteristic 

double crack of a sonic boom. Inside the XS-1’s instrumentation 

compartment, the oscillograph recorded the static and impact air pressure traces’ sudden jump on a strip of film, irrefutable proof that the 

airplane had indeed flown faster than the speed of sound. It remained 

faster than mach 1 for a little over 20 seconds, then Yeager decelerated 

back through the now-crumbled sonic wall. Fully 30% of the craft’s propellants remained when Yeager shut down the switches and began the 

long, cold glide back to Earth. There would be time enough to probe 

further beyond the speed of sound. Fourteen minutes after launch, the 

rocket plane’s wheels brushed the baked clay of the dry lakebed. The 

dreaded “sound barrier” was a thing of the past.22 

Shortly after the plane landed, as Yeager shambled off to get some 

well-earned sleep, Walt Williams placed il long-distance phone call to Gus 

Crowley and Hartley SoulC. “We did it today,’’ he said; the message 

required no explanation. At Muroc, the project team planned a party at 

Pancho’s Fly-Inn that night, but two hours after the flight, word came 

from NACA Headquarters that the accomplishment and future flight 

tests were to be regarded as Top Secret. Dryden, Crowley, and SoulC 

wanted to be certain that the XS- 1 had really gone supersonic. They had 

all of the craft’s records sent back to Langley for examination, which 

understandably annoyed Williams and his staff of professionals at the 

lakebed. 23 

18 
THE SPEED OF SOUND 

The Bell X S - 1 #I, which completed the world's first manned supersonic flight on 14 

October 1947. 

Despite a leaked account of the first supersonic flight by the trade 

journal Aviation Week in December 1947, the Air Force and NACA did 

not formally reveal Yeager's accomplishment until 15 June 1948 when 

Gen. Hoyt Vandenberg, Chief of Staff of the Air Force, and Hugh 

Dryden of NACA confirmed that the XS- 1 had repeatedly exceeded the 

speed of sound, flown by military and NACA test pilots. The announcement triggered a flood of honors and awards, including the prestigious 

1947 Robert J. Collier Trophy shared by John Stack for NACA, Chuck 

Yeager for the Air Force, and Larry Bell for the American aircraft 

industry. By the end of 1947, the XS-1 had flown to over 1490 

kilometers per hour-mach 1.35-twice as fast as a wartime P-51 

Mustang. The XS-1's success encouraged the Air Force to order four 

advanced versions from Bell, of which three were eventually completed 

(the X-lA, X-lB, and X-1D). The Air Force phase of the twopronged assault on the speed of sound had clearly been a success; the 

service reached the maximum flight speed of the XS-1 on 26 March 

1948 with a flight by Chuck Yeager to mach 1.45 (1540 kilometers per 

hour). 

At the same time NACA was turning its efforts away from support of 

the Air Force program and to flying its own XS- 1, the thicker-winged 

19 
ON THE FRONTIER 

The NACA Muroc Contingent in October 1947, in front of the NACA XS-1. 

second aircraft. Herb Hoover had completed its first glide flight on 21 

October, a week after Yeager’s accomplishment; embarrassingly, during 

the landing, Hoover touched down hard upon the nosewheel, collapsing 

it and necessitating repairs that kept the craft grounded until midDecember. On 16 December* he checked out the craft at subsonic 

speeds. Though pleased with its flying qualities, he recognized that the 

brief amount of flight time at high speed imposed by the rapid consumption of rocket propellants reduced the amount of information that could 

be acquired from each flight. “It’s going to take a long flight program 

with a lot of flights,” Hoover pessimistically but accurately concluded in 

his flight report.24 

Another and more critical problem was workload. By early 1948, the 

NACA unit was ministering to three airplanes: the Air Force and NACA 

XS-1s and the second Douglas D-558-1 Skystreak, which the agency 

had received at Muroc for testing by its pilots. Workload posed a serious 

problem for the instrumentation staff, since the NACA believed in 

thoroughly instrumenting and calibrating its research airplanes. In one 

case, three instrument technicians with the Muroc unit put in over 250 

hours of overtime in the period from 10 November through 13 Decem- 

*Because of a peculiar handling characteristic during its landing flare, the XS-1 series was 

prone to land hard, overstressing the nosewheel. Nosewheel collapses plagued the Bell, NACA, and 

Air Force programs on all XS- Is, including the advanced models procured later. 

20 
R a * b * 

THE SPEED OF SOUND 

ber 1947. Williams placed the XS-1 project ahead of every other 

research activity.25 

There was no longer any doubt that the XS-1 could safely exceed 

the speed of sound, but the NACA test team did wonder what differences 

might stem from the thicker wing on its airplane. Drag would certainly 

increase; there might be other undesirable traits as well. So Hoover 

approached the now-punctured “sound barrier” cautiously. Following a 

series of proving flights to increasing mach numbers, Hoover made his 

first high-speed run on 4 March 1948, when he reached mach 0.943 at 

12 000 meters. Six days later he flew to mach 1.065, slightly over 1100 

kilometers per hour, becoming the first NACA pilot and the first civilian 

to fly faster than sound; subsequently, he received the Air Medal from 

President Harry Truman for the feat. On the last day of the month, 

Howard Lilly became the second NACA pilot to “break the Mach,” and 

NACA had now firmly joined the growing supersonic club. 

The Muroc engineering staff immediately set to reducing the 

accumulated data from the XS-1 program and generated ten formal 

NACA research memoranda on the airplane’s handling qualities, flight 

loads, stability and control characteristics, and pressure distribution 

surveys.26 The XS- 1 tests by Hoover and Lilly-and subsequent ones by 

Robert Champine and John Griffith, who arrived at Muroc in late 1948 

and late 1949, respectively-generated significant aeronautical information. 

NACA continued flying the craft in the vicinity of mach 0.90, for the 

agency was interested in investigating the exact conditions of flight at 

velocities around the speed of sound and in acquiring data that could be 

used for correlation with ground-based wind-tunnel data. The engineers 

were especially intrigued by the pronounced increase in controllability 

that the adjustable stabilizer provided the XS- 1 at transonic speeds; that 

work constituted a pioneering effort in the development of the “allmoving” horizontal tail surfaces that later appeared on the first-generation 

supersonic jet fighters such as the F- 100. As a result of XS- 1 research, 

Soul6 could write in late 1949 that “the power-driven adjustable stabilizer has already become standard equipment in new transonic-speed 

tactical airplane design^."^' NACA XS - 1 testing also indicated, with 

shocking impact, just how much drag thick wing sections added at 

transonic speeds. The NACA XS-1, with its 10% thicknesskhord ratio 

wing, had 30% more overall drag at transonic speeds than did ‘the 

thinner wing Air Force XS- 1. Thick-wing sections simply imposed 

unacceptable penalties for transonic and supersonic airplane design. 

There were serendipitous benefits from XS- 1 research as well; the 

extensive calibration of airspeed measurement systems in the XS- 1, 

together with the results of ground radar tracking, provided a data base 

for building advanced air speed measurement systems for high-speed 

21 
t 

ON THE FRONTIER 

airplanes. In a short period of time, then, the NACA XS- 1 effort made 

notable contributions to aviation science, complementing the Air Force 

effort with Glamorous GZennis and justifying the hopes of the planners of 

the XS- 1 joint program. The supersonic assault had been a success.28 

22 
2 

Pioneer Days at Muroc: 1948- 1950 

Muroc Air Force Base in early 1948 was not only remote, it was 

bleak. In December 1947, NACA's work came to a standstill as personnel scrambled away to celebrate the holidays in more appealing sections of the country. Indeed, one reason for the impressive amount of 

work that got done might have been sociological: there was little else to 

do. Even by automobile, a trip to Los Angeles was a chore; without one, 

the remaining choice was the afternoon Stage Lines bus that left Muroc 

for Los Angeles at about 5 p.m. The voyager had to spend the night in 

Los Angeles and take another bus back the next evening.' Word about 

the discomforts of Muroc soon spread within the NACA labs, making 

recruitment very difficult. Other events soon exacerbated this situation. 

NACA-MUROC: UNWELCOME TENANT OR VALUED PARTNER? 

Over the summer of 1947, when Langley had decided to establish 

the test team at Muroc permanently as the Muroc Flight Test Unit, 

personnel officers had journeyed to Muroc to ask the workers if they 

wished to stay on as regular staff, thus losing their $3 and $4 per diem as 

employees on temporary duty. Those who chose to leave were paid for 

the return to Hampton.2 During the first year of its existence, the Muroc 

unit experienced a high turnover in personnel; workers quickly split into 

two groups-those who adjusted to the heat, dust, and grit of the desert, 

and those who could not stand the environment for more than a few 

weeks. Many stayed because of job satisfactions not readily apparent. 

They believed they were participating in a program of great national 

importance that would radically alter the future development of aviation; 

they considered it both a great responsibility and an honor to have been 

selected to work on the program. Nevertheless, by January 1948 the 

morale of the NACA unit at Muroc had begun to slip; the long days and 

nights of work were taking their toll. Unhappily, the local Air Force base 

administration had to bear a great deal of responsibility for the conditions at Muroc. 

23 
ON THE FRONTIER 

In January 1948, Edmond C. Buckley, the chief of Langley’s 

instrument division, visited Muroc and was appalled by what he saw. His 

ascerbic memo to Hartley Soul6 was read by Langley Laboratory 

Director Henry J. E. Reid, who- thought that Buckley had perhaps 

exaggerated the situation. Reid journeyed to Muroc and was equally 

shocked; Buckley had been right on target. Buckley’s memo first discussed the housing situation. The junior married professional staff 

quarters were acceptable by Langley standards. The senior married 

professional staff quarters, however, were vastly inferior to what a 

comparable couple could expect at Langley. The married quarters for 

mechanics were “the equivalent of emergency wartime living condition^."^ 

Quarters for the single engineers or mechanics were “all Grade A fire 

traps.” The Air Force vigilantly made certain that occupants of base 

housing did not have unauthorized furnishings in their domiciles. In one 

case, an Air Force inspector discovered “an illegal broken-down chair” in 

one of the NACA quarters and “left the quarters in such a fury that the 

door came off the hinges and fell on him.” Lavatory facilities were mostly 

communal, and locked doors were not permitted because of fire hazards. 

Buckley disliked the Muroc Officer’s Mess as well, commenting that 

“for cleanliness, this is not equal to a Hampton or Phoebus pool hall. 

There have, however, been no deaths although dysentery had run 

through the group.” Some NACA personnel chose to eat at the GI Mess 

at North Base. Buckley ate there and reflected that “the sad lot of the 

European DPs came to my mind.” 

Work areas consisted of open hangars, bitterly cold in December and 

January, which lacked darkroom facilities. With both XS- 1 aircraft flying 

and the NACA Douglas Skystreak in its checkout stage, the chances for 

leave were poor; most workers were putting in large amounts of 

overtime. For amusement, Buckley concluded, “one has the choice of 

working or going to bed to keep warm. Reading or writing in your 

quarters is impracticable because of facilities and temperature.” As far as 

social life, Buckley wrote, “Muroc should be staffed with misogynists. 

The future offers nothing.” The staff at Muroc was obviously under strength, 

but three new arrivals were all that Buckley thought he could persuade to 

leave Langley for the desert. 

Walt Williams desperately needed better living and working conditions for his staff. He wanted a hangar for the exclusive use of NACA, 

office areas colocated with the hangar, and men’s and women’s dormitories. 

NACA already shared the East Main Hangar with the Air Force, but it 

had inadequate office, shop, and stock space, and the electrical system 

was incompatible with NACA’s instrumentation requirements. Blowing 

dust seeped into the work area, compromising satisfactory instrumentation work. Williams wished to move into another hangar and construct 

24 
PIONEER DAYS AT MUROC 

offices from wood and sheetrock with suitable electrical and plumbing 

installations. Not one to make waves, he was willing to get NACA to 

furnish all the materials and labor if the Air Force would just approve the 

construction, though it was simpler for the Air Force to furnish the 

materials through the Air Materiel Command, with NACA furnishing 

the labor.4 Further, Williams wanted the service to turn over a building, 

“T-83,” to the NACA for use as a dormitory. But all his plans hinged on 

winning the cooperation of the base administration. 

During Henry Reid’s Muroc visit, the Langley chief had met with the 

commanding officer of Muroc Air Force Base, mentioning, as Reid later 

noted, that the NACA needed information on the cost of Muroc quarters 

“in order that we might ask Congress for money to construct some for 

our employees.” The base commander, Col. Signa Gilkey, was unimpressed, 

and Reid later wrote that his request “was like waving a red flag, as 

Colonel Gilkey made it very clear that he did not want other activities 

spending money for permanent installations at Muroc.” Colonel Gilkey 

was also opposed to turning over Air Force buildings to the NACA. In his 

notes on the trip, Reid emphatically stated: “In general, the living 

conditions and the attitude of the commanding officer are such as to be 

demoralizing to everyone. . . . My contacts with the commanding officer 

lead me to believe that one of the things he is afraid of is that if 

contractors and the NACA are allowed to fix up quarters and improve 

their situation, they must allow the Navy the same privilege, and 

eventually control of the base would be lost.” Reid concluded that the 

only real solution would come when the NACA personnel had housing 

available in Lancaster, 50 kilometers away, “where civilians can live a 

normal civilian [and, by implication, civilized] life.”5 

In truth, the situation was more complicated than Reid thought. 

Colonel Gilkey had drawn up an ambitious “Master Plan” for the 

expansion of Muroc, wherein the base would expand to take in nearby 

Rosamond Dry Lake to the west, reroute the railroad tracks that bisected 

Muroc’s dry lake and limited its landing area, and add a 4500-meter 

runway and new building and housing areas. All this would take 

approximately $120 million, and the new facility would include schools 

and shopping areas. (Eventually, all this did come to pass, and it is fair to 

say that Colonel Gilkey was the architect of the modern Air Force Flight 

Test Center complex, a tribute to his foresight.) But he feared that 

complying with the NACA’s requests for improvements to existing 

structures would delay implementation of the master plan. 

The NACA quickly solved its Muroc difficulties to its satisfaction. 

After his return to Langley, Reid took up the matter of the Muroc staff 

with SoulC, Crowley, Dryden, and others, and the matter eventually 

went to Jerome Hunsaker and the NACA Main Committee itself. Air 

25 
a 

ON THE FRONTIER 

Force committee members quickly supported the plans for the Muroc 

unit, and in April, Williams received title to the long-sought hangar and 

access to Air Force materials. Within the NACA structure, Ames Laboratory was directed to support the Muroc effort, and in May NACA 

personnel, including model makers and technicians from Ames, began 

work on lean-to offices along the sides of the newly acquired hangar. 

Construction was completed on the shops and offices in November 1948, 

and the men’s and women’s dormitories were finished the next spring. 

Muroc was still not a bed of roses, but at least conditions were a bit more 

tolerable.6 

In retrospect the brief spat between the local Air Force administration and the NACA was a sorry little affair that served to mar the 

otherwise excellent cooperation (if friendly rivalry) that existed between 

NACA and the Air Force at Muroc. It was a remarkably similar pattern to 

that of the Army-NACA relations over the Langley laboratory in 

1918- 1920.’ Certainly on the operating level there were no interagency problems, just lots of teamwork and sweat. Any lingering difficulties disappeared in September 1949 when a new commanding officer 

Brig. Gen. Albert Boyd and Walter Williams examine a model of the Northrop X - 4 

research aircraft. 

26 
PIONEER DAYS AT MUROC 

arrived on base, Brig. Gen. Albert Boyd, known throughout the service 

as “the test pilots’ test pilot.” One might have expected two strong-willed 

and dynamic individuals such as Boyd and Williams to strike sparks, but 

this was not the case. A strong bond of friendship, respect, and 

cooperation formed between these two, and the Boyd-Williams relationship soon proved fruitful both for the NACA and the Air Force.8 

NACA- MUROC LOSES HOWARD LILLY 

There was yet another unhappy episode in the spring of 1948, this 

one truly tragic: Howard Lilly was killed on a research flight in the 

NACA Skystreak on 3 May 1948. 

Understandably, the NACA Skystreak program had played second 

fiddle to the XS-1 throughout late 1947 and into 1948. Not only was it 

recognized that the plane could not compete with the XS- 1 in terms of 

maximum speed capability (even while diving, the Skystreak eventually 

touched mach 1 only once), but it had extensive requirements for 

instrumentation that delayed its flight readiness. NACA technicians 

worked on this craft when they did not have anything to do on the 

XS- 1, and were able to make two familiarization flights in Skystreak by 

the end of 1947. 

The Skystreak had the same general aerodynamic configuration as 

the XS- l-a straight wing and tail, both thinner than conventional 

design practice. Here the resemblance ended, for the D-558-1 (as it 

was designated) took off from the ground under its own power, propelled by a General Electric TG- 180 turbojet engine. The Douglas 

company had built three of the D-558-1 Skystreaks, which preceded 

the firm’s three D-558-2 Skyrockets. An agreement among all the 

agencies concerned affirmed the planned delegation of responsibilities 

on the Skystreak program: Douglas would fly the first Skystreak in a 

series of company tests; NACA would get the second and third Skystreaks, 

maintain them, fly them with fuel and oil from the Air Force, and 

perform major aeronautical research; the Navy would accept responsibility for engine overhaul and replacement; and Douglas would perform 

the major maintenance and modification work, drawing upon Navy 

funding. This arrangement, confirmed for NACA by a Navy memo on 4 

November 1947, was followed until the retirement of the Skyrockets a 

decade later.g 

Though the second Skystreak had earlier set a world’s airspeed 

record of 1047.13 kilometers per hour, the NACA-Muroc unit quickly 

discovered that the craft was something of a jinx. The landing gear often 

failed to lock fully in the retracted position; on one flight, Lilly had to 

land hurriedly after the cockpit filled with dense smoke from a small 

27 
ON THE FRONTIER 

electrical fire. Ground trackers watching the scarlet-colored airplane 

through tracking photo-theodolites discovered that the aesthetically 

pleasing plane was very difficult to see against the dark blue desert sky, so 

the fuselage was painted glossy white to facilitate optical tracking-aside 

from the high-temperature Blackbirds and X- 15, all NASA research 

aircraft since have been white or other light colors. On 29 April 

1948, Lilly reached mach 0.88 in the plane, part of a planned flight 

program investigating directional stability at transonic speeds. lo 

On 3 May Lilly took off from Muroc at noon; as the maintenance 

staff had come to expect, he had to land because the balky landing gear 

once more failed to lock properly. Minor adjustments occupied most of 

the afternoon, and it was not until late that Lilly tried again. With a 

lowering sun already casting lengthening shadows, the ground crew 

readied the plane for flight. Lilly ran up the engine, the TG-180 

emitting a rising wail, and started his takeoff, the jet finally lifting off 

after a run of about 1 Vi kilometers. Witnesses saw the landing gear fold 

up into the plane; the Skystreak accelerated. Then, somewhere within 

the jet engine’s compressor section, strain became too great and some 

component failed. In the whirling compressor, such a failure had all the 

catastrophic impact of the flywheel of a huge steam engine coming apart. 

Whole sections of the compressor housing and blades slashed through 

the engine casing and through the fuselage skin. Some pieces cut the 

main fuel lines and severed the craft’s control lines as well. Lilly had no 

control over the plane, whose tail section erupted in flames. Today, in the 

era of “zero-zero” (zero altitude/zero airspeed) ejection seats, he might 

Test pilots Eugene May (left) and Howard Lilly at Muroc with the second Douglas 

0-558-1 Skystreak. 

28 
PIONEER DAYS AT MUROC 

have had a chance. But all the ailing Skystreak had was a jettisonable nose 

section so the pilot could abandon it at high altitude. Witnesses saw the 

jet, low over the dry lake, shed a large section of fuselage skin, followed 

by a gout of flame-streaked smoke. Horrified, they watched the Skystreak 

wallow along for a few seconds before sickly slipping into a left yaw and 

roll, dive into the lakebed, and explode. Howard Clifton “Tick” Lilly, a 

five-year NACA veteran and the third pilot to fly faster than sound, 

became the first NACA test pilot killed in the line of duty.” 

Lilly’s death deeply affected the Muroc staff. It was still a small 

group, no more than 40, and the gregarious Lilly, with his West Virginia 

twang, had been a close friend of many. The accident especially shocked 

the safety-conscious Williams. Langley Laboratory, the administrative 

headquarters for Muroc, established an accident board, chaired by 

veteran NACA pilot Me1 Gough. The board reached the conclusion that 

disintegration of the engine compressor section had severed critical 

control and fuel lines. Both Williams and the accident board urged that 

all future research aircraft have the latest model engines, incorporating 

all up-to-date engine modifications and changes (the unfortunate Skystreak 

had had an early model TG- 180, not up to standard as compared with 

later TG-180s on other aircraft). They also insisted that all research 

aircraft incorporate armor plating around the engine in the vicinity of 

control lines, fuel and hydraulic lines, and fuel tanks. Subsequently, 

NACA was most uncompromising at contractor’s “mock-up” inspections 

when the question of protecting planes from disintegrating engines came 

up. Lilly had given his life, but he would be remembered: visitors to the 

Dryden Flight Research Center drive down Lilly Avenue from Rosamond 

Boulevard. And inside the administration building, on the second floor, 

hangs a portrait of this promising and sorely missed test pilot. 

Exactly two weeks after Howard Lilly died at Muroc, Ames laboratory test pilot Ryland Carter perished when a P-5 1 H Mustang broke up 

during a dive. These two accidents, coming after years of a safe research 

record, caused certain persons to suggest that the NACA use contract test 

pilots for NACA flight research, offering-as private industry didbonuses for hazardous aircraft testing. Hugh Dryden called a headquarters meeting to thrash out an answer. Herb Hoover represented the 

Langley-Muroc group, and Larry Clousing, another NACA test pilot 

with a distinguished flying record, represented Ames. Hoover and 

Clousing, as well as the other NACA pilots present, were adamant that 

NACA pilots fly NACA research aircraft. Dryden concurred and rejected 

any further consideration of using non-NACA pilots on NACA research 

aircraft projects. l2 

The death of Lilly caused a temporary shutdown of NACA flight 

operations at Muroc. Herb Hoover had returned to Langley after Lilly 

29 
ON THE FRONTIER 

The NACA X - 1 (formerly X S - I) research aircraft. 

had checked out both in the NACA XS-1 and the ill-fated NACA 

Skystreak. Now Hoover returned briefly to the desert to train a replacement pilot, Robert A. Champine, who had considerable flying experience 

with the sweptwing Bell L-39 research airplane, a background that 

made him particularly well qualified for the upcoming NACA program 

at Muroc on the sweptwing Douglas Skyrocket. Sweptwing airplanes had 

tricky behavior at low speeds and during abrupt maneuvering flight. 

Champine completed his first flight at Muroc on 23 November 1948, 

when he checked out in the NACA XS- 1. Hoover returned to Langley 

for good in December.* NACA-Muroc was back in the air.13 

“X-SERIES” ADMINISTRATION 

The hiatus in flight operations at Muroc caused by Lilly’s crash did 

not mean that development of the research aircraft program was 

similarly slowed. Any impartial observer of NACA affairs in mid-1948 

would have recognized how the scope of the research airplane program 

had changed. Originally conceived for the XS-1 and D-558, the 

program had expanded to embrace an XS-2 for sweptwing mach 3 

research, an XS-3 for sustained mach 2 turbojet research, an XS-4 for 

*Hoover himself perished in the crash of a B-45 test plane near Langley on 14 August 1952 

when the plane broke up in midair. 

30 
PIONEER DAYS AT MUROC 

transonic research on the tailless configuration, and the XF-92A for 

delta wing research at transonic speeds.* Another batch of advanced 

X-1s had been ordered, and one more projected vehicle, a variable 

wing-sweep design that eventually became the X- 5, was being discussed 

by Bell, the Air Force, and NACA. Each of the NACA laboratories was 

busily at work on phases of the research aircraft program: Arnes and 

Langley were doing wind-tunnel research on configurations, Lewis was 

following up with engine work on turbojets, and the Pilotless Aircraft 

Research Division (PARD) at Wallops Island was firing off models of 

proposed research aircraft. l4 The research aircraft program involved 

extensive dealings with outside parties: the military services financed the 

development of the aircraft and their engines, and private contractors 

manufactured them. Already the load of paperwork and administrative 

chores had justified the appointment of an administrative officer, Marion 

Kent, to the Muroc unit in April 1948. Increasingly Hugh Dryden came 

to believe that the NACA research airplane effort required a central 

point of focus for coordination and communication. Eventually, this led 

to the creation of the NACA Research Airplane Projects Panel (RAPP). 

Since 1945, Hartley A. Soul6 had been acting as NACA’s chief of 

research airplane projects and activities, and his duties had dramatically 

increased. On 9 August 1948 Dryden recognized those increased responsibilities by making Soul6 a member of his staff as the agency’s 

Research Airplane Projects Leader. The laboratories were told that “the 

research airplane program involves all laboratories as well as the Muroc 

Unit, and the program coordination is therefore a function of NACA 

 headquarter^."'^ Soul6 would report to Dryden’s deputy, Gus Crowley, 

on research airplane matters. Soul6 wasted little time in expanding upon 

the project leader concept. Desiring to improve interlaboratory communications and relationships on the research aircraft, Soul6 sent a memo to 

NACA Headquarters at the end of the month recommending the 

establishment of a special research airplane panel, with a representative 

from each laboratory, headquarters, and the chief of the Muroc Flight 

Test Unit. The panel would “effect proper coordination of the interests 

of the three laboratories in Muroc projects [including] the status of the 

research airplane projects at or proposed for Muroc, the current position 

of supporting investigations at each of the laboratories, and technical 

problems relating to each project.”16 On 2 September 1948, the plan was 

approved and Soul6 was appointed hairm man.'^ Over the next two 

weeks, Soul6 notified each of the labs and Walt Williams of the panel’s 

*“XS became simply “X after 11 June 1948 as a result of a change in Air Force aircraft 

designation policy. “X is used subsequently throughout the text. 

31 
il a * 

ON THE FRONTIER 

creation, receiving in return their concurrence in the decision and 

nomination of representatives to the panel.’* 

Establishment of the Research Airplane Projects Panel under SoulC’s 

leadership codified an existing administrative relationship by giving 

SoulC’s actions the trappings of a formal bureaucratic structure. The 

action demonstrated that the program had grown to such size that it was 

no longer possible to manage or monitor it on a laboratory level. It 

required management directly from Headquarters-though, wisely, Dryden selected SoulC, the former Langley boss, for the position. With 

Dryden and Crowley at the helm, and Soul6 next, the research airplane 

program had the unequivocal support of the highest NACA echelons. 

Further, the creation of RAPP gave the NACA better and more 

streamlined coordination of the laboratories’ activities on research aircraft projects. RAPP fit smoothly into NACA’s lifestyle; since its inception 

NACA had been governed by the Main Committee and its fields of 

research overseen by specialized committees or panels. Every year, until 

abolishment of the panel on the eve of the X-15’s flight program, 

Williams submitted a detailed annual report to the panel, outlining the 

research programs at the dry lake, and the programs being planned. The 

panel was somewhat of a formality as far as Williams was concerned. In 

most cases, he won easy endorsement of his plans from the panel at its 

annual meetings, usually held early in February. Through RAPP 

participation, the laboratories learned some of the operating problems 

facing the Muroc unit, and the RAPP played a crucial role in sorting out 

some of the difficulties in the X-series development programs. 

Creation of RAPP also marked implicit recognition of another 

factor, almost a political one: the research airplane program was NACA’s 

most visible symbol of postwar research, and to an agency desirous of 

retaining its image as a far-seeing, up-to-date scientific organization (an 

image tarnished by its prewar failure to pursue turbojet propulsion), the 

glamorous research aircraft gave NACA’s public image a badly needed 

shot in the arm. Participation in the research aircraft effort had begun in 

almost casual fashion; in the memoirs of one engineer, “it took form 

gradually, manipulated and developed in innumerable lunchroom conversations and other contact^."'^ But by mid- 1948, the program had 

assumed such stature that it provided some of NACA’s strongest cards 

whenever Jerome Hunsaker or Hugh Dryden took the agency’s budget 

to Congress for approval. RAPP helped by drawing greater attention to 

the agency’s commitment to the research aircraft effort. Interestingly, it 

imposed few administrative or bureaucratic chores on program administrators at Muroc and the NACA laboratories. NACA’s traditional pattern 

of delegated authority for project management minimized paperwork 

and meetings. While the Wallops model-rocket testing program and the 

32 
PIONEER DAYS AT MUROC 

Muroc effort were exceptions-requiring interlaboratory ties within 

NACA and ties to outside organizations as well-management, in the 

reflective words of engineer John Becker, remained “delightfully simple, 

direct, unobtrusive, and inexpensive.”“ 

The same climate that helped create the RAPP and elevate Hartley 

A. Soul6 to the position of Research Airplane Projects Leader generated 

the next change in the status of the Muroc unit itself: it was time to raise it 

organizationally from the level of a detached unit under the direction of 

a remote parent (Langley Laboratory) to that of a semiautonomous 

NACA “station,” only one notch below a “laboratory.” Langley had 

designated the Muroc Flight Test Unit as a permanent appendage of the 

parent center in September 1947. Certainly, by mid-1949, NACA administrators could foresee a continuing need for the Muroc facility for at 

least a decade: the agency had plans for participation in the X- 1, X-2, 

X-3, X-4, D-558-1, D-558-2, advanced X-1, and the XF-92A 

program, as well as consultant status on some of the Air Force projects 

being tested at Muroc. Other projects, such as the gestating X-5, were in 

the discussion stage. By now, the value of having a single, specialized 

locus in the agency for flight testing of high-performance aircraft was 

also readily apparent. Muroc offered unsurpassed year-round flying 

conditions, permitting maximum utilization of research aircraft. It was 

also the Air Force flight testing center, the service that played the major 

role in financing and supporting the postwar X-series. For the NACA 

Muroc Flight Test Unit to fulfill its growing responsibilities in testing and 

research on these aircraft, it would have to expand. Already growth was 

rapid. At the time of Yeager’s flight, the unit had 27 workers. A little over 

a year later, in January 1949, it had 60. In January 1950, this had 

doubled again, to 132. Through fiscal 1949, Langley Laboratory had 

carried responsibility for funding the Muroc unit; but in August 1949, 

with the onset of FY 1950, Muroc appeared for the first time as a line 

item on its own: NACA’s FY 1950 budget, approved by Congress on 24 

August 1949, included $685 072 for the NACA Muroc unit. (By comparison, 

Langley received over $16 million.) On 14 November 1949 the Muroc 

unit was redesignated the NACA High-speed Flight Research Station 

(HSFRS), a title more accurately reflecting the broad scope of flight 

research contemplated for Muroc than the previous one.“ 

EXPANDING UPON THE SONIC BREAKTHROUGH 

The year 1949 was important to the NACA Muroc installation in 

several ways; there were, of course, the changes in the administration of 

the field site, reflected in its new title. But 1949 held particular importance as the year that the Muroc unit really resumed its research flying, 

33 
d 

ON THE FRONTIER 

suspended with the death of Howard Lilly and the loss of the NACA 

Skystreak. The year also saw active involvement with three new research 

airplanes: a replacement Skystreak, the Northrop X-4, and the sweptwing D-558-2 Skyrocket. By 1950, the Skystreak and Skyrocket had 

added significantly to the transonic aerodynamic information acquired 

by the two X-Is, and the X-4 program was causing Williams and the 

NACA staff innumerable headaches, as will be seen. 

Although in retrospect there proved to be little reason to build both 

the Skystreak and the Bell XS-1, it would have taken a gambler to 

predict that outcome before the sonic barrier was breached. The major 

reason for the Skystreak was that it could cruise for an extended time 

above mach 0.8, freeing the XS-1 for mach 0.9 and higher, thus 

complementing the research program on the rocket airplane. But this 

was a justification after the fact; when the Skystreak was first proposed, it 

was competing for the same mission as the rival XS- 1. And unlike the 

AAF-sponsored XS- 1, the Skystreak was a Navy-sponsored program. 

John Stack, NACA’s leading research airplane advocate, saw the Skystreak 

as much more in line with what the NACA wished a transonic research 

airplane to be-jet propelled and relatively conventional in concept. The 

Navy, for its part, hoped that the D-558-1 Skystreak would lead to a 

military fighter derivative. The XS- 1, in fact, was almost single-handedly 

the result of AAF research airplane advocate Ezra Kotcher and his 

unrelenting efforts to develop a mach 1.2 rocket-propelled craft. As John 

Becker has stated, it is ironic that Stack and NACA eventually shared the 

Collier Trophy for the achievements of the research airplane they least 

favored, the XS- 1 .22 Nevertheless, one should not minimize the importance of the Skystreak to NACA’s flight research effort: from 1948 

through 1952 it was the nation’s most sophisticated straight-wing turbojetpowered research airplane for transonic flight testing. 

The NACA resumed its research with the Skystreak in early 1949; by 

the end of the year, SoulC was writing that the data from the X- 1 and the 

D-558- 1 were affording “very complete coverage of design information for high-speed straight-wing airplanes from takeoff to the transonic 

speed ranges.”23 Despite its sleek appearance, tests of the Skystreak 

quashed hopes by the Navy and Douglas that they might spin-off a 

tactical fighter. As it neared mach 1, Skystreak‘s handling qualities 

deteriorated rapidly. The force a pilot had to exert on its control wheel 

for longitudinal trim increased some six times-from 22 newtons to 133 

(from 5 pounds to 30)-between mach 0.82 and 0.87. It tended to wallow 

about the sky at transonic speeds, certainly not an efficient weapon 

platform for service use.24 

The Skystreak did make one major contribution to aeronautical 

engineering practice, a contribution indicative of the relatively easy34 
PIONEER DAYS AT MUROC 

NACA’s Dough Skystreak cruises high over the Antelope Vallej during a transonic 

research flight. 

going and freewheeling managerial style that governed Muroc in the 

late 1940s. Langley’s John Stack had concluded that adding little metal 

tabs or vanes (called vortex generators) in a row running in a spanwise 

direction (wingtip to wingtip) on the top and bottom of a wing might act 

to stabilize the position of shock waves on the wing, reducing undesirable 

trim changes and raising the so-called “limiting” mach number of the 

plane. He called Walt Williams, who installed the tabs on the Skystreak by 

simply gluing them to the wing-the Skystreak had a fuel-filled “wet” 

wing that prohibited riveting. The row of generators indeed worked, 

raising the plane’s maximum controllable speed by 0.05 mach, a significant increase. Industry quickly applied the results to new aircraft such as 

the Boeing B -4’7 Stratojet medium bomber. Vortex generators subsequently appeared on many other aircraft as well. Williams was criticized 

in certain administrative circles for not securing prior approval from 

NACA Headquarters; but in his mind it was more important to secure 

results quickly and expeditiously than tie a project up in bureaucratic 

approvals. One need only compare the rapid implementation of the 

vortex generator idea with the 19’70s winglet research program to 

appreciate the simplicity and directness of the earlier approach. The 

Skystreak completed its last vortex generator research flight in June 

1950, when it reached mach 0.99, the limits of its performance. Though 

not retired until 1953, Skystreak .had reached its zenith.25 

It fell to the sweptwing Douglas Skyrocket to explore another 

interesting aerodynamic situation, this one a potentially dangerous 

35 
ON THE FRONTIER 

instability predicted by wind-tunnel tests-the pitch-up phenomenon, 

which plagued early sweptwing aircraft designs. 

The Skyrocket seemed an unlikely choice for a successful research 

airplane, given its early history. Designed for both a jet and a rocket 

engine-the rocket for high-speed boost-and to take off from the 

ground, the Skyrocket appeared in early 1948 as a graceful sweptwing 

design having only its jet engine installed because the planned rocket 

propulsion system was well behind schedule. The first Skyrocket (the 

D-558-2, as it was known) flew at Muroc on 4 February 1948, piloted 

by company test pilot John Martin. The NACA received the second one 

built at the end of the year. Following installation of an instrumentation 

package, the plane completed its first NACA research flight on 24 May 

1949, piloted by Bob Champine. The Skyrocket was not viewed favorably 

by the NACA Muroc unit. Without its planned rocket engine, the 

Skyrocket lacked the necessary thrust for really meaningful- transonic 

research. As Walt Williams later recalled, “We had to get off the ground 

before the temperature reached 80” F. You’d struggle to get to 24 000 

feet [9300 meters], using almost all your fuel for the climb, and then you 

had to dive to get to 0.9 mach. Flight endurance was thirty minutes or 

less.”26 Nevertheless, the NACA hoped that flight testing of the craft 

would complement earlier low-speed work at Langley with the L- 39, 

and a companion effort at Ames laboratory with a specially instrumented 

North American F-86A jet fighter. Happily, the NACA’s expectations 

for the Skyrocket were met, and the D-558-2 program joined the X- 1 

as one of the two most successful of the early research airplane programs. 

Skyrocket’s first brush with pitch-up came on 8 August 1949, when 

test pilot Champine banked into a tight 4-g turn at the modest speed of 

The NACA Douglas 0-558-2 Skyrocket research aircraft. 

36 
PIONEER DAYS AT MUROC 

mach 0.6. Suddenly, without warning, the Skyrocket nosed upward 

violently-its gravity force recorder indicated that the structure had 

sustained a momentary 6-g loading. Shaken, Champine applied down 

elevator, regained control, and landed. Wind-tunnel studies had indicated that sweptwing airplanes might experience the pitch-up phenomenon during “accelerated” maneuvers such as high-g turns because of 

changes in the lifting characteristics of the wing and a decrease in 

effectiveness of the horizontal tail, particularly if the plane’s flight 

attitude “blanketed” the tail from the oncoming airflow. Champine’s 

flight gave NACA aerodynamicists the first opportunity to study data 

taken during an actual pitch-up excursion, as well as a new appreciation 

of the seriousness of the problem. (During takeoff and landing, for 

example, pitch-up might stall a sweptwing airplane and plunge it into the 

ground before the pilot had a chance to recover; at high speeds, the 

danger of pitch-up might unduly restrict the maneuvering performance 

of sweptwing jet fighters.) Subsequently NACA Muroc pilot John Griffith had an even more serious encounter with pitch-up, during a similar 

4-g turn. He tried to fight the maneuver by forcing the nose down, but 

Skyrocket’s tail effectiveness was low, and the plane commenced rolling 

and yawing before spasmodically snap-rolling. Griffith recovered handily, 

but later in the same flight, while performing an approach to stall with 

the craft’s wing flaps and landing gear extended, Skyrocket abruptly 

pitched up as its airspeed dropped below 2 10 kilometers per hour; again 

Griffith tried to fight it, and this time the plane rolled into a spin, 

dropping 2 100 meters before Griffith was able to return it to level flight. 

NACA Muroc discontinued Skyrocket’s pitch-up program in 1950, when 

the agency and Navy sent the craft back to Douglas to be modified 

exclusively for rocket propulsion and air-launch from a mother airplane, 

like the Bell X- 1. Nevertheless, the NACA realized that it had encountered a serious aerodynamic problem, and the 1949 pitch-up studies 

presaged a much more thorough investigation during 195 1 - 1953 using 

another Skyrocket, about which more will be said.*’ 

In contrast to the productive work on Skystreak and Skyrocket, the 

Northrop X-4 program caused the NACA a great deal of concern 

during 1948-1950. The X-4 was a small twin-jet airplane having a 

swept wing but no horizontal tail surfaces. Instead it relied on combined 

elevator and aileron control surfaces called elevons for its control in pitch 

and roll. It was similar in general configuration to Britain’s ill-fated De 

Havilland D.H. 108 Swallow which had crashed in 1946, and NACA 

suspected (rightly so) that the X-4 might suffer from the same stability 

and control problems-especially a dangerous pitching oscillation as it 

neared the speed of sound. Some engineers within the Air Force and 

Northrop hoped that the X-4 might offer a reasonable configuration 

37 
ON THE FRONTIER 

for high-speed flight. NACA was under no such illusions, though 

engineers thought the craft might prove very useful for dynamic stability 

studies and studies of varying an airplane’s lift-to-drag ratio so as to 

understand better the behavior and handling qualities of airplanes having extremely low lift-to-drag ratios. Much of this latter work benefited 

the later X-15 program. 

The NACA had hoped to receive in December 1948 one of the two 

X-4 airplanes being built, but because of manufacturing delays the first 

airplane only completed its maiden flight that month. The contractor 

program on the X-4 did not go smoothly; the plane was, in pilot’s 

parlance, a maintenance “dog,” far worse than the Skystreak that had 

killed Lilly. Northrop’s test pilot completed only three flights in the plane 

in six months. Much against its will, the NACA Muroc technical staff 

found itself increasingly involved with the plane. It should not have been 

involved until its own aircraft arrived for testing, but Northrop needed 

help and drew upon the Muroc unit for analysis of flight test data. 

Normally, Williams would not have objected, but he had his hands full 

with the NACA X- 1, Skystreak, and Skyrocket. He simply lacked the 

manpower to perform data reduction and even engineering duties in 

support of a contractor’s program. Adding insult to injury, the company 

alleged that its delays stemmed from NACA’s slowness in working up 

data from the flights! In response to a puzzled inquiry from Hartley 

SoulC, Williams sent back a blistering memo castigating Northrop’s 

operating procedures and mechanical problems, concluding that “the 

airplane is a difficult machine to operate and the research information to 

be gained is of small value for the work involved.”28 NACA, Williams 

promised, would do what it could to support the Northrop program; 

“We, however, have better use for these people, and as has been stated 

before, the sooner we drop the project the better off we will be.”29 

The X-4 did have some NACA friends, especially Smitty De France 

of Ames, who wanted to use the aircraft as a dynamic stability research 

vehicle in support of some Ames research. Headquarters had already 

planned to rotate certain engineers through the Muroc site to familiarize 

other laboratories with the work being done in the desert, and Ames 

detailed a staff engineer, Melvin Sadoff, to the Muroc station as X-4 

project engineer. Eventually, nearly two years behind schedule, NACA 

received the second X-4, the one built for agency research; the first 

airplane made only 10 flights before being grounded as a source of spare 

parts for the second. Completing its first NACA mission in November 

1950, the second X-4 soon proved a valuable research tool for dynamic 

stability research, largely because it was a much more reliable craft than 

its predecessor. Delays such as the X-4‘s were not uncommon in 

first-generation research airplanes: with the exception of the first X- 1 s 

38 
PIONEER DAYS AT MUROC 

and the Skystreaks, all subsequent programs experienced greater or 

lesser delays-primarily, it appears, from contractors underestimating 

the work required to develop specialized research airplanes3’ 

THE END OF THE BEGINNING 

In November 1949, the Air Force had offered Glamorous Gbnnis, the 

original X- 1, to NACA as a research airplane. But NACA was already so 

committed to advanced research aircraft that Soul6 was not about to 

accept a well-worn if historic hand-me-down. He recommended instead 

that the X-1 be sent to the Smithsonian Institution. Following its last 

flight-fittingly enough, by Chuck Yeager-on 12 May 1950, it was. 

The retirement of the X-1 marked the end of the first tentative 

phase of supersonic research, the first nibbling away at the speed of 

sound, the first cautious edging beyond mach 1. The next phase would 

come with the detailed examination of transonic flight by such craft as 

the X-3, X-4, X-5, XF-92A, and D-558-2; and the continuation of 

frontier-pushing to mach 2 and 3 with the advanced X- Is, the all-rocket 

D-558-2, and the X-2. 

By 1950, the NACA was readying two large “slotted throat” tunnels 

for transonic research, one having a 2.4-meter test section useful to mach 

1.15, and the second having a 4.8-meter test section and capable of mach 

1.08. Even now, there still was a small “grey area” just around the speed 

of sound beyond about mach 0.98. The absence of ground-based 

research facilities for transonic testing that led to the early X-series 

aircraft had been overcome in rapid order largely because the X-series 

provided a research focus and an urgency that stimulated development 

of new methods of ground research and new tools such as the slotted 

throat tunnel. Because of the forcing function that the X-series imposed 

upon the development of ground research methods and tools, the 

principal accomplishments of the early X-series (the X-1 and the 

D-558- I) lay less in their providing unique new information than in 

their validating the utility of new laboratory research techniques by 

providing “real-world” comparison data taken from flight testing3’ 

Finally and most important, though, was an undeniable psychological benefit coming from the first supersonic flights of these first research 

aircraft, a benefit aptly summarized by one program participant: “The 

most basic value was the liberation of researchers and aircraft designers 

from their fears and inhibitions relative to the ‘sonic barrier.’ The 

awesome transonic zone had been reduced to ordinary proportions, and 

aeronautical engineers could now proceed with the design of supersonic 

aircraft with confiden~e.”~~ 

39 
e 
3 

Testing the Shapes of Planes 

to Come: 1950-1956 

On 27 January 1950 the Air Force held a special dedication 

ceremony at Muroc, renaming the desert facility Edwards Air Force 

Base, in honor of test pilot Glen Edwards, who had died in a test flight 

from the site in 1948. The ceremony symbolized the increasing emphasis 

that the Air Force was placing upon flight testing, an emphasis that led to 

the designation of Edwards in 1951 as the Air Force Flight Test Center 

(AFFTC) with responsibility for testing aircraft, operating other test 

facilities, and providing support and services for contractors and other 

government agencies, such as NACA. The 1950s, old-timers recall, were 

the “Golden Years” of Edwards, a period of unparalleled expansion, a 

time when new speed and altitude records were set almost monthly, and 

the boom of igniting rocket engines punctuated conversations, giving the 

center its own distinct and exciting character. The Korean War stimulated expansion at Edwards. Air Force expenditures for the base leapt 

from $3.5 million in FY 1950 to $28.7 million in FY 1955, and to $82.3 

million in FY 1960; personnel grew from 3938 to 8278 in the same 

period. The base expanded from 795 square kilometers in 1952 to over 

1214 square kilometers by mid-1955, making it the largest flight test 

center in the world.’ 

In the nine years after 1950, the NACA station at Edwards worked at 

an intensive level. The unit concluded its major role in the supersonic 

breakthrough (fittingly enough, it was a NACA pilot who first exceeded 

mach 2), tested and evaluated a wide range of vehicles having new 

configuration concepts for high-speed flight, supported the development 

of military service aircraft, and undertook theoretical studies that eventually prepared the way for the hypersonic X- 15 of the following decade. 

The station’s growth mirrored that of the Air Force installation, though 

on a smaller scale. The total complement grew from 132 in January 1950 

to 332 in December 1959, and its budget rose from $685 thousand for FY 

1950 to $3.28 million for FY 1959. (A year later, reflecting the X-15 

41 
ON THE FRONTIER 

NACA pilots plan an X - 1 research flight. 

drive, this had jumped to $6.99 million, rising to $32.97 million by 1968.) 

During the 1950s the NACA Edwards installation gained complete 

autonomy from Langley. When NACA became NASA in 1958, the station 

was redesignated the NASA Flight Research Center (FRC) on 27 September 1959, making it coequal administratively with the other NASA 

centers. * 

AUTONOMY ARRIVES 

The cutting of the umbilical with Langley was not surprising. Since 

1946, the Muroc-and then Edwards-facility had moved steadily and 

surely away from the parent. Though the work of the two centers 

complemented one another, Langley’s aeronautical thinking would always be dominated by the wind tunnel; just as thinking at Edwards would 

always be dominated by the research airplane. Since the High-speed 

Flight Research Station already reported directly to headquarters through 

Hartley Soul6 as Research Airplane Projects Leader, there was little need, 

except nostalgia, to keep the center allied firmly with Langley. But an 

autonomous center required all the trappings of a major research facility: 

it must have good quarters, research areas, and work space; an independent administration; and fiscal organization defensible before outside 

agencies. Assisting the hopes of those who sought autonomy was the 

situation with the Air Force: with the adoption of the Edwards “Master 

Plan,” the Air Force had committed itself to moving from its old South 

Base to a new location midway between the South and North Bases. The 

42 
TESTING THE SHAPES TO COME 

NACA would have to move as well-so why not take advantage of the 

situation and move into a full-blown research facility rather than sornething less? In August 1951 Congress approved $4 million for construction of new laboratory facilities for the NACA at Edwards, supplementing 

a previous grant of $919 281 covering the station’s salaries and expenses 

for FY 1952. The Air Force issued a lease to the NACA for more than ?h 

square kilometer on the northwestern shore of the dry lake, and construction started on the NACA station in early February 1953: one 

large building would have hangar space to house the research airplanes, 

shop and instrumentation facilities, and office^.^ 

By early 1954, the new site was nearing completion. A headquarters 

directive on 17 March 1954 designated it an autonomous unit effective 1 

July 1954, with the title NACA High-speed Flight Station (HSFS). The 

transition to autonomy involved a lot more than just a change in title; 

Ground-breaking for the new High-speed Flight Station facilities, 27 January (lefit to 

right): Gerald Truszynski, Joseph Vensel, Walter Williams, Marion Kent, and California 

state official Arthur Samet. 

43 
ON THE FRONTIER 

The NACA High-speed Flight Station, completed in 1954 at a cost of $3.8 million. This ZS 

still the core of the Dryden Flight Research Center. 

Edwards did not play Minerva to Langley’s Zeus. Every facet of center 

administration and operation had to be accounted for, expanded upon, 

and separated from Langley. This included budget, center management 

(already autonomous except in name), safety, establishment of a center 

library, preparation of a procedures manual, appointment of a legal 

officer, appointment of a procurement officer, selecting a color code for 

center correspondence, design of an HSFS letterhead, transmittal of 

NACA general directives and policy letters, issuance of a code letter for 

use in designating HSFS reports, appointment of a Defense Materials 

Officer, and transmitting a complete set of NACA reports to the center. 

All this took weeks to sort out. Finally, all was ready. On 26 June 1954 the 

NACA group moved from its make-do offices and hangar space on 

South Base to the nucleus of the present Dryden Flight Research Center 

facilities. They were on their 

By 1954, the NACA station at Edwards already was a research 

facility with strong in-house technical capabilities; likewise the fundamental organization of the station was well established, a basic arrangement 

still generally followed over two decades later. There were four brancheslater termed divisions and then, under NASA, directorates. These were 

administration, research, operations, and instrumentation. 

Administration, of course, meant Walt Williams and his staff. He did 

not have a deputy, though in his absence De E. Beeler often assumed the 

role of acting chief. Williams’s managerial style emphasized minimal 

44 
TESTING THE SHAPES TO COME 

NACA Headquarters officials inspect the High-speed Flight Station’s new facilities in 

1954 (left to right, front row): Jerome Hunsaker, Walter Williams, Hugh Dryden; (middle 

row) Scott Crossfield, Joseph Vensel, John Victoly; (back row) Marion Kent, De E. Beeler, 

Gerald Truszynski. 

paperwork, informal communication and decision-making, rigorous attention to time and cost schedules and, above all, an unwavering 

commitment to safety. His great flexibility in structuring management 

defies placing Williams within any of the standard industrial-organization 

schools of management such as “Theory X,” “Theory Y,” “MBO,” etc. It 

most closely mirrors the “gamesman” approach but without the “gamesman’s’’ frequently cynical view of his role within an institution. Williams 

was without question a highly effective administrator, as was his successor 

Paul F. Bikle, a man who reflected the same attributes. 

Research was supervised by De E. Beeler, an intense, hard-driving 

individualist. Research involved the center’s mathematicians, engineers, 

and physicists. This branch did the work on aircraft stability and control, 

flutter and vibration, loads, structures, performance, and other special 

research, including design conceptualization of advanced aerospace 

45 
ON THE FRONTIER 

vehicles. This group supervised the flight research portion of the aircraft 

flight-testing programs. Eventually the research branch got into aircraft 

simulation as well, for flight planning, pilot training, systems analysis, 

and performance prediction. 

Operations was the feifdom of Joe Vensel, a veteran NACA test pilot 

who ran the pilots’ office, supervised flight operations and maintenance 

of the aircraft, and helped plan and monitor the flight programs. Crusty 

but fatherly, Vensel ruled with an iron hand; somewhat deaf from his 

years in open-cockpit biplanes, Vensel had the habit of turning off his 

hearing aid and going to sleep if a meeting became boring. The test pilots 

under him maintained close liaison with the engineers in research. 

Instrumentation was the responsibility of Gerald M. Truszynski, who 

established a reputation for thoroughness that helped make him a senior 

NASA administrator a decade later. This branch undertook the instrumentation and calibration of the various research airplanes, and provided flight tracking and data acquisition services. Though HSFS occasionally did its own instrument fabrication, it generally relied upon 

Edmond Buckley’s instrumentation group at Langley for development. 

NACA still relied on a pair of old SCR- 584 radars, though it was obvious 

that as the capabilities of the X series advanced to mach 3 and beyond, so 

would the need for a specially instrumented high-speed flight corridor 

with several data-linked tracking stations. This would come to pass with 

the establishment of the X- 15 High Range. 

In a broad sense, the research aircraft program involved a cooperative effort among three parties-industry, the military services, and 

NACA. This was reflected in the way testing took place at Edwards. The 

testing process closely followed the military pattern of airplane acquisition and testing, with the difference that NACA added another aspect all 

its own. First, a contractor would build a research airplane to military 

specifications, usually derived in conjunction with NACA; this was 

particularly true for the rocket-research aircraft and the D - 558 series. 

Standard practice called for the contractor to deliver the first aircraft 

built to Edwards for so-called Phase I testing. This involved the contractor’s 

own pilots demonstrating that the airplane had generally satisfactory 

handling qualities and conformed to the contract. Then the contractor 

would usually deliver the aircraft to the Air Force, with a second craft 

going to NACA for detailed research investigations. The NACA HSFS 

would generally provide data acquisition and analysis support to the 

contractor and the Air Force on their programs. 

Despite the oft-heard claim that the military and contractor programs were “scientific research,” more often than not, especially on the 

rocket-propelled aircraft, the programs were little more than contractor 

verification of the plane’s flying qualities, followed by repeated attempts 

46 
TESTING THE SHAPES TO COME 

by the contractor and, later, the service, to set new speed and altitude 

records. Such flying was always viewed with disfavor by the NACA 

because it seemed an unnecessary risk of expensive research tools. The 

De Havilland D.H. 108 lost in Britian, for example, had been destroyed 

during a practice speed run for a planned airspeed record flight attempt. 

Aside from seeking records, service research tended to emphasize 

pragmatic military values rather than the niceties of aerodynamic and 

propulsion studies; as has been mentioned, the Navy closely watched the 

Skystreak program to see if it could spawn a tactical airplane. The Air 

Force evaluated the Bell X-5 variable-sweep aircraft to see if it could be 

modified into a cheap fighter for NATO and other foreign countries. As 

part of the Air Force Cook-Craigie acquisition plan (to be discussed 

subsequently), NACA laboratories around the country received currentgeneration military aircraft for flight testing in support of the military 

research and development programs on these aircraft. NACA-Edwards 

tested many of these aircraft as well. 

Generally speaking, then, flight testing at NACA-Edwards during 

the 1950s involved research on the X-series aircraft and research support 

on various military aircraft programs. The X series itself broke down into 

two major subcategories of aircraft: configuration explorers-aircraft 

having unique and unusual design shapes requiring verification or 

refutation, such as the X-3, X-4, X-5, XF-92A, and, to a lesser 

extent, the D -558 - 2 Skyrocket-and supersonic aerodynamic research 

vehicles having rocket propulsion and being air-launched from modified 

Boeing B-29 or B-50 bombers-such as the advanced X- Is, the 

all-rocket D-558-2 Skyrocket, and the Bell X-2. The configuration 

testbeds were rarely flown beyond mach 1, because most were simply 

transonic in performance. The X-3, for instance, was a planned mach 2 

configuration testbed that failed to fly anywhere near that mark because 

the manufacturer had to use less powerful engines than originally 

intended. The third D-558-2 Skyrocket, which retained both jet and 

rocket propulsion, is included in the configuration group because of its 

extensive sweptwing pitch-up investigations undertaken during the 1950s. 

The rocket-propelled supersonic research aircraft, on the other hand, 

were the aircraft that first exceeded mach 2 and 3. 

In the mid-1950s the research aircraft program continued to expand. 

Soul6 and other program officials could see three broad streams: the 

early rocket research airplanes and configuration explorers, a hypersonic 

research vehicle that soon became the X- 15, and, beyond, a true winged 

orbital spacecraft (termed a “boost-glider”) known as “Dyna-Soar” (for 

Dynamic Soaring). These roughly sequential streams or “rounds” caused 

Hartley Soul6 to dub the early rocket research aircraft and configuration 

explorers “Round One.” The X-15 became “Round Two,” and the 

47 
R 

ON THE FRONTIER 

Dyna-Soar became “Round Three.” This after-the-fact classification 

quickly passed into the NACA’s official records and n~menclature.~ 

NACA’s CONFIGURATION EXPLORERS 

The High-speed Flight Research Station’s research on new aircraft 

really involved studies of aerodynamic, stability and control, and handling qualities on five basic configurations: the sweptwing, the semitailless, 

the delta wing, the variable-sweep wing, and the low-aspect-ratio thin 

wing. 

Configuration Aircraft Speed Range 

Sweptwing Douglas D-558-2 #3 Mach 1.0 

Semitailless Northrop X-4 #2 Mach 0.9 

Delta wing Convair XF-92A Mach 0.9+ 

Variable-sweep Bell X-5 #1 Mach 0.9+ 

Low AR thin wing Douglas X-3 Mach 0.95 

All these aircraft were also associated with particular aerodynamic 

research or dynamic stability problems as well. 

Aircraft Research Problem 

Douglas D-558-2 #3 Sweptwing pitch-up during 

maneuvering. 

Northrop X-4 #2 Pitching oscillation of increasing 

severity approaching mach 0.95. 

Convair XF-92A Delta pitch-up during maneuvering. 

Bell X-5 #1 

Douglas X-3 

Unacceptable stall-spin behavior: 

sweptwing pitch-up during 

maneuvering. 

Coupled motion instability during 

abrupt rolling maneuvers. 

Each of these problems was a major concern to an aircraft industry 

undertaking the design of new combat aircraft vastly different in 

configuration and speed potential from those of only five years before, 

and to the Air Force and Navy, whose pilots might have to fly and fight in 

these new designs. Thus, any detailed understanding of these difficulties 

would be welcomed as a significant contribution. 

With the exception of the Douglas X-3, each of the other four 

configuration explorers exhibited some degree of pitch-up problem, 

ranging from moderate to severe. Of all five aircraft, the only one having 

generally pleasant flying characteristics was the D-558-2. The others 

48 
TESTING THE SHAPES TO COME 

NACAs early X-series fleet (from lgt): Douglas 0-558-2 Skyrocket, Douglas 0-558-1 

Skystreak, Bell X-5, Bell X-1, Convair XF-92A, Northrop X- 4. 

exhibited the following behavior characteristics, which generally stemmed 

either from the peculiar configuration or the lack of a powerful enough 

engine: 

Aircraft Behavior Problem 

Northrop X-4 #2 Poorly damped “hunting” motion 

about all three axes; “washboard 

road”motion. 

Convair XF-92A Sluggish and underpowered. 

Bell X-5 #I Dangerous stall approach and spin 

tendencies. 

Douglas X-3 Sluggish and very underpowered. 

After exploring the basic behavior of the aircraft and its characteristics, 

NACA generally made aerodynamic modifications to the design to 

evaluate whether certain concepts such as wing leading edge extensions 

or wing fences would improve the behavior. If they did, NACA concluded that these were generally applicable design features that could 

improve the behavior characteristics of that type of configuration. Such 

modifications were not attempted with the X-3 and X-5 because of cost 

and complexity considerations. Modifications evaluated on the other 

three aircraft were: 

49 
* 4 w 4 

ON THE FRONTIER 

Aircraft Modifications 

Douglas D-558-2 #3 Various wing slat and wing fence 

combinations, leading edge 

extensions. 

Northrop X-4 #2 Increasing the thickness of the 

trailing edge of the wing and elevon. 

Convair XF-92A Various combinations of wing fences. 

Aside from a coupled-motions instability investigation on the X-3, the 

problem of greatest interest to the industry and military services was that 

of pitch-up, encountered in various forms by the D-558-2, the XF-92A, 

and the X-5. 

Pitch-up was a problem inherent in any sweptwing or delta airplane. 

As a sweptwing airplane approaches a stalled flight condition-either at 

low speed by flying at an increasingly higher nose-up angle of attack and 

a lower and lower speed, or at high speed in an abrupt turning maneuver 

at a high-g loading-the natural tendency of the airflow around the wing 

is accentuated, notably the tendency of the airflow to flow outward 

toward the wing tips (spanwise flow), promoting the development of 

so-called “separated” airflow, causing a loss of lift at the wing tips. As the 

stall condition progresses, the area of the stall moves progressively “up” 

the wing toward the wing root, followed by the center of lift of the wing. 

Put another way, the zone of wing lift becomes smaller and smaller and 

concentrated toward the fuselage, hence further “forward” along the 

plane’s longitudinal axis. The change of lift vector to a point further 

forward along the len th of the plane causes the plane to nose abruptly 

Pitch-up could be overcome by several “fixes”: a “sawtooth” leading 

edge extension would promote the formation of “active” airflow, defeating the tendency of the wing to exhibit spanwise flow; wing fences, 

literally small “fences” running in a chordwise (leading edge to trailing 

edge) direction to divert the spanwise flow into chordwise flow; and open 

wing slats (dating from the 1920s) to delay the onset of turbulent 

separated airflow over the wing at high angles of attack. All these were 

examined on Skyrocket and XF-92A. The best solution was to place the 

horizontal tail low on the aft fuselage of an aircraft, where it would be 

below the wing wake and downwash of the wing. Skyrocket and the X-5 

both had highly placed horizontal tails, giving them particularly objectionable pitch-up characteristics. The RAPP suggested adding a low horizontal tail to both for evaluation purposes, but the problems and cost 

outweighed the potential benefits. In any case, the obvious conclusion 

from NACA testing as to the desirability of the low horizontal tail surface 

led to that configuration’s becoming standard on the first-generation 

50 

upward-to pitch up. 8 
a +i * 

TESTING THE SHAPES TO COME 

One NACA attempt to remedy pitch-up: chord extensions on the NACA 0-558-2 #2, 

photographed in February 1953. 

supersonic sweptwing fighters such as the North American F- 100 Super 

Sabre and the Vought F8U Crusader. Sweptwing supersonic aircraft 

lacking such a feature-such as the McDonnell F- 101 Voodoo-proved 

to have dangerous and mission-limiting pitch-up characteristics. Tail 

changes, of course, could not be made with the triangular or delta wing 

configuration; rather, designers had to rely on various combinations of 

wing fences. 

The several NACA programs on Skyrocket, the X-4, XF-92A7 

X-5, and X-3 went relatively smoothly from a standpoint of data 

collection, analysis, and reporting. But maintenance often proved 

troublesome; highly complex experimental aircraft, then and now, are 

notoriously difficult to keep up even under the best of circumstances. 

NACA workload, program, and weather considerations also played a 

role, often forcing a stretch-out of planned flights. Skyrocket, for 

example, took 27 months to complete 29 pitch-up research flights. In the 

following comparison, contractor and military test flights prior to NACA's 

acquisition of the aircraft are excluded. 

Aircraft Number of Flights Duration of NACA Tests 

Douglas D - 558 - 2 #3 66 1950- 1956 

Northrop X-4 #2 82 1950- 1953 

Convair XF - 92A 25 1953 

Bell X-5 #I 133 1952- 1955 

Douglas X-3 20 1954- 1956 

51 
h 

ON THE FRONTIER 

The NACA test pilot staff at Edwards approached all these aircraft 

with caution.* Skyrocket had its quirks, but was generally pleasant. The 

X-4 could be annoying. The XF-92A required good piloting skills. The 

X-3 and X-5 had truly vicious characteristics, particularly the latter’s 

violent stall-spin instability, which eventually killed Air Force test pilot 

Ray Popson. Not unexpectedly, research aircraft often have characteristics that are demanding, but the X-5 was simply a flawed design, 

although this had nothing whatsoever to do with the feature the craft was 

developed to verify, the variable-sweep wing. Rather, it had to do with its 

aerodynamic layout, especially the poor position of the tail and vertical 

fin. An excerpt from a pilot report gives some idea of its qualities as the 

plane approached a stall: 

As the airplane pitches, it yaws to the right and causes the airplane to roll to 

the right. At this stage aileron reversal occurs; the stick jerks to the right and 

kicks back and forth from neutral to full right deflection if not restrained. It 

seems that the airplane goes longitudinally, directionally, and laterally 

unstable in that order.’ 

During one flight pilot Joe Walker lost 6000 meters while recovering 

from a stall; fortunately, the stall had occurred at 12 000 meters.8 

Despite its faults, the X-5 was an outstandingly productive airplane. 

Early testing of the craft had demonstrated that the variable-wing-sweep 

principle worked-that it endowed a plane with good low-speed performance when the wing was fully extended for takeoff and landing, and 

that it offered good high-speed performance as well when the wing was 

swept fully aft. The actual mechanism by which the X-5 “translated” its 

wing from fully extended to fully swept and back again was quite another 

matter, for it was complex and hindered the utility of the design. Indeed, 

variable sweep aircraft did not become a practical reality until after the 

conceptualization of the outboard wing pivot by NACA engineers at 

Langley in the mid-1950s. NACA was not too concerned over the 

variable-sweep aspect of the plane once it had been proved to work. 

Rather, the NACA and the RAPP viewed the unique advantage of the 

X-5 to be its ability to provide a whole range of sweptwing research 

aircraft in one vehicle. Since the wing could be swept to many different 

positions, a variety of measurements were possible over a wide range of 

sweep angles, up to 60O-the same angle as the XF-92A deltasg The 

pitch-up investigation on the X- 5 complemented the extensive work 

undertaken in Skyrocket, especially since the craft could furnish aerody- 

*NACA pilots Champine and Griffith were joined by A. Scott Crossfield, Walter P. Jones, 

Joseph A. Walker, Stanley P. Butchart, John B. McKay, and Neil A. Armstrong. 

52 
TESTING THE SHAPES TO COME 

At top, NACA’s Bell X - 5 variable-sweep research aircraft with wings fully extended at 

minimum sweepback. Below, wings of the X - 5 are fulb swept to maximum sweepback. 

53 
ON THE FRONTIER 

namic information on how a wide range of sweptwings reacted as a plane 

approached its pitch-up point. NACA also used the X-5 as a chase plane 

for other research aircraft, because it could vary its flying characteristics 

to suit the airplane it was chasing. It was retired from service in late 

1955.’’ 

NACA’s research program on the little X-4 was particularly fruit-‘ 

ful for reasons not expected when the airplane was under development. 

NACA had never been a strong supporter of the X-4, a sweptwing 

airplane designed for transonic flight minus a horizontal tail to damp out 

any pitching tendencies. Indeed, the craft came about as a result of two 

factors: John Northrop’s own firm belief in the value of the tailless 

concept, and German interest in the idea, which had spawned the 

wartime Messerschmitt Me 163, a plane with very poor high-speed 

behavior. In the postwar climate of military research, any idea the Nazi 

government had been working on often assumed an imagined worth all 

out of proportion to its true value. Then the airplane had encountered 

development delays, and the first prototype proved, in-Walt WilliTms’S 

own words, a “lemon.” But the second was quite reliable mechanically, 

and the NACA program proceeded smoothly following the first NACAflight in November 1950. 

At first the NACA program concentrated on the X-4’s dynamic 

stability problems. At about mach 0.88, it began a longitudinal pitching 

motion of increasing severity; test pilots compared it to riding over a 

washboard road. But it also exhibited combined pitching, rolling, and 

yawing motions of increasing severity, a “hunting” about all three axes 

marked by inadequate motion damping as mach number increased. The 

Edwards project team decided to thicken the trailing edge of the wing in 

an effort to cure the motions, not difficult since the X-4 had huge 

speedbrake surfaces above and below the wing that could be wedged 

open, the gap between their surfaces forming the necessary “edge.” In 

1952 the engineers went further and thickened the trailing edge of the 

elevons (the control surfaces the X-4 used for pitch and roll control) 

using balsa wood attachments. The thickening worked in part, increasing 

the craft’s roll rate by 25%, and longitudinal control effectiveness was 

improved as well. But the persistent motions still appeared above mach 

0.9, and at 0.94 were so severe the plane porpoised along at vertical 

accelerations of 2 1 ?42 g. Clearly the semitailless configuration was unsuitable for transonic applications if one chose any shape resembling the Me 

163, D.H. 108, or X-4.” 

But if the X-4 configuration itself proved unsuitable, the amount of 

research data returned was substantial, particularly on the interactions of 

combined pitching, rolling, and yawing motions-an interaction soon to 

be of critical concern with high-performance military fighters. The blunt 

54 
a B * ii 1 

TESTING THE SHAPES TO COME 

NACA’s Northrop X - 4 semitailless research aircrafi, one of the smallest ever flown. 

elevon research with the X-4 directly benefited the Bell X-2 then 

under development, which featured ailerons having a blunted trailing 

edge on the basis of models tested at Wallops. The High-speed Flight 

Research Station was able to verify the full-scale concept by demonstrating the pronounced benefits the blunted trailing edge gave the X-4 in 

rolling performance. Finally, Williams and his researchers recognized 

that the X-4’s speedbrake enabled the plane to vary its lift-to-drag ratio 

to such a degree that it could simulate the approach of what are now 

termed lifting reentry spacecraft. The X-4 had a minimal lift-to-drag 

ratio of less than 3, giving it X- 15-like performance. And, indeed, it was 

with the upcoming generation of X- 15-like craft in mind that the NACA 

undertook approach and landing studies of their predicted behavior 

using the X-4. It ended its days as a pilot trainer before being retired in 

1954.’* 

By NACA standards, the HSFRS program on the XF-92A deltawing research aircraft was a brief one, lasting only six months in 1953 

with 25 flights. The XF-92A had an interesting past, for it was not 

originally conceived as a research craft at all, but rather as a testbed for a 

proposed interceptor that failed to materialize. Once the Air Force had 

abandoned the proposed interceptor, the service continued to support 

development of the XF-92A, only one of which was built, as a delta 

testbed. NACA interest in the plane was immediate, for the delta wing 

planform offered exceptional wing area plus a thin airfoil cross section 

and low aspect ratio, combined with low weight and high structural 

55 
c a 

ON THE FRONTIER 

strength-all desirable attributes for a supersonic airplane. Even before 

its first flight in 1948, NACA had tested the plane in the full-size 

low-speed tunnel at Ames. The RAPP closely followed the actual Convair 

and Air Force program on the airplane, which the Air Force relinquished 

to the NACA in early 1953. 

Besides validating the thin delta principle, the XF-92A played a 

major role in supporting the development of the Convair F-102A 

interceptor, the Air Force’s first attempt at an all-weather supersonic 

interceptor. The XF- 92A had surprisingly violent pitch-up characteristics during turns, often exceeding 6 g and once going above 8 g. NACA 

technicians at Edwards equipped the craft with various wing-fence 

combinations planned for the F- 102, which had a similar wing planform, 

The Convair XF- 92, a delta-wing research aircraft. 

56 
TESTING THE SHAPES TO COME 

and the Air Force’s Wright Air Development Center requested that 

NACA send any data from its flight program that might prove beneficial 

to the F- 102 program. This NACA did, especially with regard to fence 

combinations to alleviate pitch-up. Eventually, however, the F- 102 faced 

major redesign anyway, to take advantage of the Whitcomb area rule 

principle derived at Langley and the conical wing camber concept 

derived at Ames. Nevertheless, the contributions of the XF-92A to the 

F-102, and through the F-102 to the XF2Y-1 Sea Dart, the F-106 

Delta Dart, and’ the B-58 Hustler, were substantial. (It is interesting to 

note that, like Convair with the XF-92A7 F-102, F-106, and B-58, 

French aircraft manufacturer Marcel Dassault followed a similar development path, going from a small delta testbed, the Mirage I, to the Mirage 

I11 fighter family, and thence to the B-58-class Mirage IV supersonic 

bomber.) The XF-92A was retired in October 1953, the progenitor of 

America’s delta aircraft. l3 

Of all NACA’s configuration explorers, the only disappointment was 

the best-looking of the lot, the Douglas X-3. Conceived for supersonic 

research above mach 2, the X-3 had been victimized by an experimental 

engine installation that failed to live up to its promise. Rather than two 

powerful turbojets, the X-3 had to be completed with puny (by 

comparison) Westinghouse J34s, which could not propel the airplane 

past mach 1 in level flight. The X-3 proved frustrating for NACA. It 

had perhaps the most highly refined supersonic airframe of its day as 

well as other important advances, including one of the first machined 

structures and the first use of titanium in major airframe components. It 

had a long fuselage, giving it a high fineness ratio, and a low aspect ratio 

(low ratio of span to chord) wing having a thicknesskhord ratio of only 

41/2%. Despite this potentially supersonic configuration, the maximum 

speed ever attained by the X-3 was mach 1.2 1 , during a dive. For a while, 

the RAPP thought about replacing the jet engines with two rocket 

engines and after fairing over the plane’s air intakes, launching it from a 

modified jet bomber to reach mach 3.5. But the X-3 was overtaken by 

events-namely, the development of the F-104, a genuine mach 2 

airplane to which it directly contributed. 

The X-3 had made its first flight in Ocotber 1952. It was so badly 

underpowered that on the first flight its test pilot, Bill Bridgeman, 

complained into his mike, “This thing doesn’t want to stay in the air,” 

which might have been taken as an epitaph for the whole program. In 

July 1954, the Air Force completed its own brief evaluation of the craft, 

by now regarded as a glamorous “hangar queen,” and turned it over to 

the High-speed Flight Station, whose engineers judged the plane to have 

only “limited” research utility. It did have some contributions it could 

make. One-not to be minimized-was to tire studies: the plane routinely 

57 
ON THE FRONTIER 

shed its small tires during high-speed landing and taxi runs, forcing 

revision of tire design criteria for high-performance aircraft. l4 

The X-3 completed its first NACA flight in August 1954, and by 

late October, the HSFS X-3 project team expanded the planned 

program on the aircraft to include investigating its lateral and directional 

stability and control during abrupt rolls with the pilot holding the rudder 

“fixed” (centered). These studies had particular significance, for the X-3 

closely approximated the then-current generation of military fighters 

entering testing or production. They had a short wingspan and a long 

fuselage, with the aircraft “loaded” primarily along the fuselage rather 

than along the wing. This lack of spanwise loading greatly increased the 

plane’s inertia characteristics in yaw and pitch. On 27 October 1954 NACA 

test pilot Joe Walker had the dubious honor of demonstrating just how 

dangerous flight testing can unexpectedly be, and how courage must 

always be the constant attribute of the successful test pilot. As planned for 

this flight, Walker initiated an abrupt left roll at mach 0.92 and an altitude of 9100 meters. The plan rolled rapidly, but as it did so the nose 

rose in pitch and simultaneously slewed in yaw, reaching combined values of 20” in pitch and 16” in yaw. After five wildly gyrating seconds, 

Walker regained control. He had every reason to call it a day and land, 

but such was not Joe Walker’s style. With curiosity aroused, Walker accelerated in a shallow dive past mach 1 and then executed an abrupt left 

roll. This time the reaction was more than violent; it was berserk, with the 

plane attaining a sideslip angle of 2 lo, imposing a transverse load of 2 g. 

Simultaneously, the plane pitched violently downward, reaching - 6.7 g, 

then violently pitched upward to + 7 g before Walker could regain control. 

Fortunately, the rolling motions subsided; without further difficulty 

Walker damped the yawing and pitching motions and landed immediately. 

Postflight analysis indicated that the fuselage had sustained but fortunately had not exceeded its maximum limit load, while the high angle of 

attack has prevented the wing from reaching its limit load. Joe Walker 

was a skillful-and lucky-man. l5 

NACA wisely decided not to duplicate the flight conditions Walker 

encountered that exciting day over the Mojave. The “inertial coupling” 

phenomenon that Walker encountered had first appeared in very mild 

form in the dynamic instability of the X-4 at transonic speeds. Concurrently with the X-3 experience, however, were a series of accidents 

occurring on the first production F-100A Super Sabre jet fighters. 

Though attributable in part to a serious lack of directional stability, the 

progression of violent motions mimicked the X- 3 experience closely. 

Inertial coupling, also called roll coupling or roll divergence, had first 

been predicted by William H. Phillips of Langley Laboratory in a classic 
r Ir P R e 

TESTING THE SHAPES TO COME 

theoretical study.16 One important cure was to increase the wing area 

and, especially, the tail surface area of the aircraft. Such a cure turned 

the F-100 from a killer into a reliable airplane. Walker’s experiencelike the early pitch-up encounters of Champine and Griffith-gave 

agency engineers their first “real-world’ appreciation of how serious the 

inertial coupling problem could be. What pitch-up was to the early 

sweptwing jet aircraft, inertial coupling became to the first-generation 

supersonic airplanes. Generally speaking, the current-generation aircraft 

having twin vertical fins and generous wing areas plus other aerodynamic 

refinements are monuments to the lessons learned from the X-3 and its 

brethren. 

In many ways, Walker’s flight remained the apex of the X-3 

program. Though it returned the X-3 to the air, NACA was most 

reluctant to probe its lateral (roll) stability and control characteristics 

further, and finally retired the craft in 1956.” 

One little-known configuration program run by the High-speed 

Flight Station involved a special investigation for the Navy and the 

Atomic Energy Commission on the transonic drag characteristics of 

bomb and tank shapes-“external stores”-hung off the wing of an 

airplane. The bomb and tank shapes of the early 1950s did not differ 

appreciably from those of World War 11, and aerodynamicists faced 

The Douglas X-3, NACA’s glamorow hangar queen. 

59 
ON THE FRONTIER 

serious fI ow-interference problems generated by hanging these bulky 

shapes on otherwise streamlined airplanes. “Low drag” external stores 

shapes compatible with the new generation of attack aircraft-attack 

aircraft designed to carry nuclear weapons-were still largely a thing of 

the future. The military services and agencies such as the AEC that had 

to generate new weapons wondered how these new shapes would affect 

the transonic drag rise of high-speed attack and fighter aircraft. The 

danger, of course, was that the shapes would impose unacceptable 

penalties in range and maximum speed. 

In 1951-1952, the AEC and Navy approached NACA, urging the 

agency to study the problem. Walt Williams proposed a program to add 

stores pylons to the Skyrocket, the aircraft used for NACA’s pitch-up 

research, and test bomb shapes and fuel-tank shapes produced by 

Douglas. Douglas was a natural choice and was in on the program from 

the start: it designed the Navy’s string of first-line attack aircraft, the AD 

Skyraider, A3D Skywarrior, and A4D Skyhawk. The RAPP quickly 

assented to Williams’s proposal, and D-558-2 #3 began its stores 

research program in the summer of 1954, continuing until December 

1955, when NACA engineers concluded they had sufficient information. 

The data were delivered to the Navy and AEC for use in weapon 

design.18 Nine months later, this Skyrocket was retired from service, the 

last of the “Round One” configuration explorers to fly. 

MAKE-WORK OR VALUABLE CONTRIBUTORS? 

The progression of aeronautical technology has been accompanied 

by radical changes in the shapes of aircraft. Certainly, designers in the 

mid-to-late 1940s and early 1950s faced conflicting choices of configurations for high-speed aircraft. There were some general trends, such as 

lengthening a plane’s fuselage to increase its fineness ratio while reducing the wingspan to lower its aspect ratio, reducing the thickness of 

wings, and placing the horizontal tail clear of the wing wake. But a 

diversity of choices and decisions faced designers as well: should a plane 

have a moderately sweptback wing (say 35”) or a sharply sweptback wing 

(45” or more)? How thin should a wing be? Should supersonic aircraft 

employ delta wings? Should the plane have a horizontal tail? What 

high-lift devices would work best on a sweptwing plane for low-speed 

flight? These and many other questions required answers, answers that 

the “Round One” configuration explorers provided. 

NACA always maintained that its work on the configuration explorers was of critical importance to postwar aircraft design. A few critics in 

industry (perhaps motivated, as historian Alex Roland has suggested, by 

a “not invented here” syndrome) believed that the postwar X-series 

60 
t c ir a 

TESTING THE SHAPES TO COME 

program did not materially assist the design development of subsequent 

high-performance aircraft. Specifically, these critics of the program 

attacked it on three general grounds: 

The program was expensive, time consuming, and distracted the 

industry and military services from developing practical, operational supersonic aircraft. 

o The program failed to generate any improvements to turbojet 

engine propulsion systems. 

The stability and control information gathered was not applicable 

to advanced aircraft design because it was gathered from shapes 

not representative of what future high-performance aircraft would 

look like.” 

The first charge is easy to refute. Industry and military researchers 

had no clear ideas of what a “practical,” “operational” supersonic aircraft 

should look like. In retrospect, the designs they generated prior to access 

to X-series information were almost always wildly impractical.“ The 

leading service aircraft of the 1950s and 1960s (especially the Air Force’s 

“Century Series” fighters, the F- 100, F- 101 , etc.) were all designed to 

incorporate features recommended as the result of the X-series testing 

program. 

The second charge is really a non-issue. The X-series program began 

as an aerodynamic research program concerned with transonic and 

supersonic flight conditions, including stability and control and flight 

loads. To acquire these data, rocket-propelled aircraft had to be designed, 

because conventional turbojets lacked the necessary power to propel craft 

past mach 1. Had the services insisted upon jet propulsion for these 

aircraft, perhaps some acceleration of jet engine development would 

have taken place, but it is doubtful. Instead, it is likely that the acquisition 

of supersonic flight data would merely have been delayed. The first 

supersonic jet fighter flew in 1953 and by that time the rocket-propelled 

advanced X-1 was pushing mach 2.5. In any case, responsibility for 

advanced turbojet studies was not a concern of the X series; it was a very 

separate issue, involving industry, the military services, and, within NACA, 

the specialists of the Lewis laboratory. 

The third charge is simply false. Of all the “Round One” configuration explorers, only the X-4’s weird semitailless shape did not appear on 

subsequent high-performance aircraft-and for good reason. Much of 

the stability and control information gathered from these aircraft warned 

designers what to adopt and, perhaps more important, what to avoid: 

high horizontal tails, small and inadequate vertical fins, configurations 

61 
ON THE FRONTIER 

prone to pitch-up or inertial coupling, etc. And this was the purpose of 

the program. 

The cost criticism is not a serious one, either. The original XS-1s 

cost approximately $500 000 apiece, equivalent to the purchase of five 

production Lockheed P-80 subsonic jet fighters, a reasonable price for 

the information gained. What was often annoying about the X-series was 

how demanding their maintenance could be, but that has been and 

continues to be a facet of research aircraft operation. Even this could be 

misleading. Sometimes the rocket research aircraft were grounded for 

extended periods of time because of engine maintenance for their launch 

aircraft-the B -29 family always had a history of troublesome engine 

problems. In sum, the X-series program and especially the configuration 

explorers did not constitute a drain or a waste of valuable research 

resources. In fact, quite the opposite is true. 

Finally, one must remember that a most important NACA function 

was its communication of research results to industry and other government branches. The results of X-series research did not lie buried in the 

files of the High-speed Flight Station, but entered the technical literature 

through the standard NACA reporting format, chiefly the research 

memorandum. Typically slightly less than a year would pass between the 

gathering of results from a research flight and its publication in RM 

form. Informally, many NACA reports were circulated to the other NACA 

laboratories and to industry in advance of their actual publication date. 

Even the few critics of the X-series program admit that it was standard 

design practice for industry to rely on NACA reports for data and 

information. This same pattern was repeated with the reports generated 

by X-series testing, including tests of X-series aircraft in NACA wind 

tunnels.*l 

In conclusion, the X-series aircraft program and the extended 

NACA testing of these aircraft constituted an important and valuable 

aspect of post-1945 American aviation. The work the agency did on the 

early supersonic configuration testbeds gave the United States a commanding lead in the field of supersonic aircraft design, so that by the end 

of the 1950s the military services were equipped in numbers with a wide 

range of combat aircraft capable of supersonic operation. 

62 
c 

4 

Through Mach 2 and 3: 195 1 - 1959 

While exceeding the speed of sound had been a great unknown, 

there were other no less important unknowns involved at double or triple 

the velocity of sound. What particularly interested researchers were the 

potential problems of stability and control that might arise at mach 2 or 3. 

They already recognized that above mach 2, aerodynamic heating would 

become an increasingly serious problem to conventional aluminum 

aircraft structures and would favor more exotic alloys and structural 

materials. 

There was no organized program to develop specialized mach 2 

research vehicles as there had been to develop the XS- 1 and Skystreak; 

there did not need to be, for the X- 1 family proved perfectly amenable 

to the task, as did Skystreak's follow-on, the D-558-2 Skyrocket. To 

see why this was so, it is necessary to consider briefly the technical 

development of the X- 1 and Skyrocket families. 

When first designed by Bell, the original XS- 1s were planned for a 

maximum speed potential of around mach 2, thanks to a large fuel 

capacity that gave the craft about four minutes of powered flight time. 

But during development, troubles with a special kind of fuel pump (a 

turbine-driven device powered by steam generated by the decomposition 

of concentrated hydrogen peroxide passed over a catalyst) forced Bell to 

complete the first two airplanes with a fuel-feed system incorporating 

high-pressure nitrogen; this reduced the amount of fuel that could be 

carried and limited the design to a maximum speed of about mach 1.45. 

Bell retained the third of the three planned XS- 1s for later completion 

with a turbopump system if it became available. Thus equipped, the 

X- 1-3 (as it was known) would be capable of exceeding mach 2, possibly 

reaching mach 2.4. In 1948 the Air Force began development of the 

advanced X- 1 s, which not only incorporated turbopump fuel systems, 

but were lengthened to give even greater fuel capacity for potential 

performance well in excess of mach 2, and possibly beyond mach 2.5. 

The advanced X- 1s were all intended for Air Force military-related 

testing. With these aircraft under development, the Air Force lost all 

63 
h L 

ON THE FRONTIER 

interest in the incomplete X-1-3 and went so far as to cancel its 

development. NACA interest in acquiring a mach 2 X- 1 to continue the 

work begun with the agency’s own X-1 caused the Air Force to 

reconsider its decision. The X- 1 - 3 arrived at Edwards for contractor 

testing in 195 1, the same time that the first of the advanced X- 1s (the 

X-ID) arrived at the lake. 

The Skyrocket program had taken a different turn. Douglas had 

completed the first and second of the sweptwing planes with only jet 

engines, pending installation of a rocket engine when it became available. 

As events turned out, the company was not able to fly the rocket in the 

plane until 1949. After takeoff from the ground, even using both jet and 

rocket engines, the Skyrocket could reach a maximum speed of mach 

1.08 in level flight at 12 200 meters, disappointingly low. Also there were 

safety problems: the heavily laden Skyrocket, brimming with fuel, 

required a 5-kilometer ground run for takeoff, imposing severe strain on 

its landing gear. Douglas sometimes fired the rocket engine to assist the 

takeoff, but this burned valuable fuel and limited the plane to about 

mach 0.95 at altitude-a speed the jet-only NACA airplane could already 

reach in a dive. NACA engineers recommended modifying the NACA 

Skyrocket to an all-rocket, air-launched research airplane. First, air 

launching would improve safety. Second, the conserved rocket fuel 

would enable the plane to exceed mach 1.5, far higher than it could attain 

from the ground. Third, an all-rocket version of the sweptwing Skyrocket could substitute in part for the lagging Bell X-2 program, already 

falling behind schedule (as will be discussed).* Accordingly, in 1949 

Hugh Dryden proposed to the Navy that the NACA Skyrocket then 

being tested at Muroc be modified for all-rocket air-launch configuration, 

giving it potential mach 1.6 + performance. The Navy agreed to sponsor 

the project, amended the Skyrocket development contract, and in early 

1950 the NACA Skyrocket left Muroc for the Douglas plant, returning as 

an all-rocket research airplane in November of that year. 

THE YEAR OF PROMISE 

The year 195 1 offered the possibility that either the Navy-sponsored 

Skyrocket or the Air Force-sponsored advanced X- 1 (the X- ID) would 

*It must be remembered throughout the story of the postwar high-speed aircraft research 

program that design of new fighter aircraft followed hard on the heels of flight-testing of research 

aircraft. Not until the large advances in research data provided by the X-15 in the 1960s did the 

data base outdistance the needs of the day. Throughout the 1950s a gain of even a few months in the 

availability of high-speed research data could mean marked improvement in operational aircraft 

then in design. 

64 
THROUGH MACH 2 AND 3 

be the first aircraft to exceed mach 2. The genuine sense of scientific 

urgency that had attended the first mach 1 flights did not exist to the 

same degree for the mach 2 mark, which was more of a psychological 

goal than a critical technological challenge. It was NACA’s nature to 

undertake a detailed step-by-step flight testing program, increasing 

mach number slowly, until the mach 2 was attained. NACA really did not 

have any control over the situation, except in the case of their own 

X- 1-3, newly arrived at the lake and awaiting its first tests. Otherwise, 

the situation was in the hands of the Navy and the Air Force, the 

respective champions of the Skyrocket and the X- ID. NACA had always 

been torn between the public-relations payoff of record-setting versus 

the dangers it entailed for expensive research aircraft. With detailed 

research programs ready for the Skyrocket, the RAPP and Williams’s 

station engineers could do little but watch and wait, concerned at the delay 

before they would get the plane and also concerned lest this bit of rivalry 

between the services lead to recklessness. Ironically, the NACA had the 

last word in the mach 2 sweepstakes, for the crown others so eagerly 

sought eventually fell into the hands of the High-speed Flight Research 

Station. 

The Douglas test team on the Skyrocket had the first shot at mach 2. 

All through the spring and summer of 1951, company test pilot Bill 

Bridgeman piloted the D-558-2 at increasingly higher speeds. On 7 

August he attained mach 1.88 (2027 kilometers per hour), well above the 

previous 1540 kilometers per hour attained by Chuck Yeager in the 

X-I, but still short of the magic mach 2. During its supersonic flights, 

the Skyrocket exhibited a highly objectionable and possibly extremely 

dangerous rolling motion (lateral instability) that was apparently aggravated by a basic flaw in the craft’s dynamic stability characteristics. NACA 

studied its behavior in detail before attempting its own high-mach flights 

in the plane. Douglas wisely never attempted to go beyond the mach 1.88 

mark, and, having done its best for the company and the Navy, delivered 

the plane to NACA toward the end of the summer.’ 

All eyes next turned to the Air Force on the X-1D. Though this 

plane had made but one contractor test flight-a glide flight at that-the 

Air Force was so eager to break mach 2 that the test pilot, Frank “Pete” 

Everest, had been advised to “see what it could do wide open.”2 On 22 

August 1951 the launch plane went up carrying the X-ID but had to 

cancel the planned launch because of mechanical problems. On the way 

back to base, the X- 1D exploded and caught fire, and the launch aircraft 

crew had to jettison it hastily into the desert, fortunately without injury to 

anyone in the planes or on the ground. With the demise of the X-1D 

vanished Air Force hopes to break mach 2 before year’s end. Then, on 9 

November 1951, following a “captive” flight, the X- 1-3 blew up under 

65 
ON THE FRONTIER 

its own launch airplane, seriously injuring Bell test pilot Joe Cannon. 

Accident investigators blamed the loss of X- 1D on electrical ignition of 

fuel vapor, and the loss of the X-1-3 on possible fracturing of a 

high-pressure nitrogen gas storage system used to purge propellants 

from the rocket plane’s tankage and propellant lines. While investigators 

may have been correct about the loss of the X- 1-3 (independent testing 

by HSFRS confirmed the tendency of its nitrogen “bundle” to fracture 

when jolted, and scattered tubing was discovered as far as 75 meters from 

the accident site), such was not the case with the X- 1D. The X- ID was 

the first in a series of three accidents that finally would be attributed to 

explosive gasket material used in its fuel system.” 

The year ended, then, with the loss of two valuable research planes, 

one launch aircraft, and the injuring of a test pilot who fortunately 

recovered to fly again. Mach 2 remained unattainable for the near 

future, pending the arrival of the remaining advanced X- 1s or the 

resumption of high-mach flights by the Skyrocket. In any case, the 

NACA was still several years away from acquiring a mach 2 straightwing research aircraft, a most frustrating and annoying situation. 

Preparing to mate the Bell X-1-3 to its Boeing B- 50 Supef’tress launch vehicle. 

*The cause, discovered by HSFS in 1955, will be discussed subsequently in relation to NACA’s 

X- 1A program. 

66 
d f P B ? 

THROUGH MACH 2 AND 3 

THROUGH MACH 2, OR NACA IN THE LIMELIGHT 

On 20 November 1953 A. Scott Crossfield, a NACA research pilot, 

became the first human to exceed mach 2. NACA had seized the chance 

to surpass mach 2 before the Air Force succeeded in doing so with the 

Bell X-1A. It came as a logical result of a two-year flight testing 

program that had so thoroughly explored the Skyrocket’s behavior above 

mach 1 that no nasty surprises would await the Skyrocket team as the 

plane approached mach 2. 

The testing had revealed that the Skyrocket’s major difficulties 

above mach 1 stemmed from dynamic instability when the plane flew at 

low angles of attack with low load factors - for example, pushing over 

into level flight from a climb while having less than a l-g force on the 

airplane. Under these circumstances, the craft’s lateral stability decreased 

markedly, and it would manifest the dangerous rolling characteristics 

noted by Bridgeman during the Douglas program In August 1953, 

Crossfield equaled Bridgeman’s earlier mach 1.88 mark. Now the Navy 

entered the scene. 

By the summer of 1953, the advanced X-1A had arrived at 

Edwards for testing, and the “racetrack” atmosphere that permeated the 

base sharpened. As with the Skyrocket-X-1D rivalry of two years 

previously, it now appeared that the Skyrocket and X- 1A were locked in 

a friendly but serious rivalry to first exceed mach 2. None of this 

would have meant much had the traditional NACA posture of leaving 

record-setting to others remained in effect. But now two factors changed 

this, one from the Navy, and the other from inside the High-speed Flight 

Research Station itself. 

The year 1953 held special significance for the American aviation 

community, for it was the 50th anniversary of the Wrights’ first flight at 

Kitty Hawk. The Navy’s Bureau of Aeronautics requested that a Marine 

test pilot, Marion Carl, be allowed to make a series of high-altitude 

high-mach flights using the NACA Skyrocket, NACA facilities, and the 

NACA Skyrocket launch team. Williams recognized that the flights were 

more for publicity than scientific reasons. He himself had been petitioning NACA headquarters (to no avail) for permission to exceed mach 2 for 

scientific purposes, and he was not enthusiastic about the Navy reentering the program with a new pilot. Williams sidestepped the first request. 

But NACA was pursued by increasingly higher circles within the Navy- 

“School ties,” Williams recollected later, “started flying all over the 

country.” The marine’s flights received NACA’s go-ahead.3 There was a 

legitimate research objective: Carl would be testing an experimental 

pressure suit for high-altitude flight. Though he came close, Carl did not 

exceed Crossfield’s speed mark even when he reached a new unofficial 

altitude record of 25 370 meters. By the end of August 1953, the 

67 
ON THE FRONTIER 

Skyrocket once again seemed out of the running for mach 2-unless 

NACA tried its hand. 

But by then the record-setting bug had clearly bitten the NACA 

Skyrocket test team, especially its project pilot, Scott Crossfield. After 

Carl’s flights, the Skyrocket team had added extensions to the nozzles on 

the plane’s rocket engine, boosting its thrust by a small but important 

amount and also preventing the exhaust flow from impinging upon the 

rudder of the plane at supersonic speed, thus improving the plane’s 

chances for mach 2. On 14 October 1953, six years to the day since 

Yeager’s historic flight, Crossfield touched mach 1.96. NACA pilot and 

plane were now the fastest in the world, but Hugh Dryden immediately 

clamped secrecy on the accomplishment and told Crossfield not to 

attempt mach Z4* Dryden would have had to ground Crossfield and 

disband the rocket team to stop them, however; mach 2 had become their 

Holy Grail. 

Crossfield set out to work around the restriction. He approached an 

old friend who worked for the Navy’s Bureau of Aeronautics. The friend 

spoke to former Navy test pilots at higher levels in the Pentagon. Within a 

week of Crossfield’s entreaty, Dryden notified Williams that the Skyrocket was cleared to attempt a mach 2 flight. Of course, Williams had 

been pressing for such a clearance for months, as the next logical step in 

the ongoing high-speed investigation^.^ 

NACAs 0-558-2 #2 Skyrocket, thefirst aircraft tofly twice the speed of sound, piloted by 

Scott Crossfield. 

*As the negotiator of the interagency agreements on the research aircraft program, Dryden was 

well aware of the services’ intention that records were to go to them, data to the NACA. 

68 
? * 

THROUGH MACH 2 AND 3 

The race was on. Over on the Air Force side of the base, a technical 

team readied the X-1A. The Air Force had definite plans to exceed 

mach 2 before the anniversary of the Wrights’ flight and, of course, 

before the Skyrocket as well, if possible. Yeager, the service’s best 

rocketplane pilot, had been instructed to make the attempt. But the 

X- 1A was brand new and required a lot of preparation. The Skyrocket 

team, on the other hand, was used to operating that aircraft and had 

learned its operating quirks and problems. Skyrocket had the first crack 

at the mach 2 mark and the NACA team did not miss its shot. In 

preparation for the flight, engineers under the direction of Donald R. 

Bellman computed an optimal flight path for the aircraft so that it would 

waste neither fuel nor energy. Technicians chilled the plane’s alcohol fuel 

so that the craft could carry more of it and then insulated it by taping all 

panel cracks before covering the plane with a coat of wax. 

At mid-morning on 20 November 1953, Skyrocket took off from 

Edwards under its Superfortress launch aircraft. The climb to launch 

altitude took over an hour, during which time Crossfield-sick with 

flu-entered the plane and readied it for flight. Finally came the launch, 

and Skyrocket dropped away from the bomber, its sleek waxed shape 

glistening in the sun. Crossfield fired the engine and began its carefully 

progammed climb, neither too steep nor too shallow. At 22 000 meters 

he began a pushover into level flight, continuing until the Skyrocket was 

in a shallow dive. The machmeter edged toward 2. Everything worked: 

the nozzle extensions provided extra thrust, Bellman’s flight plan was the 

right one, the engine ran longer than normal because of the extra fuel, 

and Crossfield’s piloting was excellent. At 18 900 meters the Skyrocket 

nosed past mach 2, reaching mach 2.005. The engine continued to run 

for a few more seconds before starving itself. The deceleration jerked 

Crossfield forward in the straps; the plane had a lot of drag. He edged 

out of the shallow dive and set up a deadstick approach to the lake. While 

coasting down, he exuberantly victory-rolled the airplane before landing. 

The Skyrocket never again approached mach 2; NACA could not again 

justify the extensive preparations. In any case, the plane simply had no 

additional performance left in it. It soldiered on for a few more years in 

mundane research tasks until its retirement in mid-1957. The X- 1 had 

reached mach 1, but mach 2 belonged to the Skyrocket.‘ 

The Air Force was not about to let the NACA’s record stand for any 

length of time. By early December, Yeager was fully checked out in the 

X- 1A. The friendly rivalry between the Skyrocket and X- 1A teams at 

Edwards in 1953 did not damage the close cooperation between NACA 

and the Air Force on the actual flight testing of the rocket airplanes. The 

X- 1A depended for instrumentation support upon the NACA station, 

and though the NACA engineers were not able to instrument the aircraft 

69 
ON THE FRONTIER 

as thoroughly as they would have had it been a NACA vehicle, they did 

install an airspeed-altitude recorder and an accelerometer that later and 

unexpectedly proved quite valuable. They also provided radar tracking 

for the flight. On 12 December 1953, Yeager set out to break the 

Skyrocket’s records.’ 

Were this simply a good story, it would play little part in the history 

of Dryden; but Yeager’s flight was one of the most significant of the early 

rocket flights. It highlighted the serious stability difficulties that could be 

encountered at mach 2 speeds, a subject of vital interest to NACA and 

particularly the Edwards station. 

On the basis of NACA Langley wind-tunnel studies, data taken from 

previous flights, and analog simulations using a Bell Corporation performance analyzer, program engineers suspected that the X- 1A and other 

advanced X- 1 aircraft would have rapidly deteriorating directional 

stability above mach 2.3. During Yeager’s flight, the X- 1A reached mach 

2.44 at an altitude of 22 600 meters. At that altitude, despite the plane’s 

speed, the dynamic pressure was so low that the X-1A’s controls were 

not completely effective in damping any sudden motions the craft might 

begin. The expected deterioration in directional stability simply reflected 

the need for much larger vertical fins for high-speed flight. Now, at mach 

2.44, the plane suddenly went out of control, beginning a slow roll to the 

left. As Yeager corrected, the roll reversed and the plane began a rapid 

The Bell X - 1 A glides back to a landing at Edwards after a research flight, trailed by a 

North American F-86D Sabre chase plane. 

70 
THROUGH MACH 2 AND 3 

roll to the right; he attempted to correct, but the X-1A violently 

snapped to the left and then tumbled completely out of control, throwing 

Yeager about the cockpit-he cracked the inside of the canopy with his 

helmet. In 51 seconds the aircraft fell 15 000 meters, decelerated from 

2570 to 270 kilometers per hour, and encountered a maximum of 11 g. 

Yeager kept seeing the Sierra Nevadas flash by; he wondered where the 

plane would hit. It eventually wound up in an inverted spin; thanks to his 

consummate piloting skills, Yeager was able to recover into a normal 

(upright) spin, and thence into level flight at very low altitude. He glided 

back onto Rogers Lake. The NACA accelerometer told an eloquent story 

of the forces the plane had encountered. 

The High-speed Flight Research Station issued a summary report by 

Hubert M. Drake and Wendell H. Stillwell explaining as fully as possible 

the difficulties likely to be encountered by a straight-wing airplane with a 

relatively small vertical tail area during a flight in the tricky regions near 

mach 2.” The X-1A never again flew near mach 2; its sister ship, the 

X- lB, made one flight to mach 2.3 a year later. Its wings rocked as much 

as 70 degrees before test pilot Pete Everest cautiously slowed the plane 

and regained stability. The advanced X- 1s might be capable of reaching 

mach 2 safely, but any edging beyond was risky at best.8 

So 1953 ended with mach 2 having been attained a mere six years 

after mach 1 had fallen to the X- 1. As with the first mach 1 flights, 

however, the attainment of mach 2 still left a great deal of research to be 

done on particular flight conditions at this speed. Indeed, the detailed 

work still lay in the future, with other aircraft programs. The NACA 

looked forward, for example, to the X-IA, which it hoped to use in a 

detailed program of high-altitude mach 2 research. The agency also 

hoped to use the X-1B for a study of aerodynamic heating conditions 

near mach 2. But events can have a funny way of working out; in this case, 

NACA’s plans would fall completely apart. 

THE DEMISE OF THE X- 1A 

In 1951, the X-ID and X-1-3 had blown themselves out of 

existence, and in May 1953 the second X-2 did likewise. The X-2’s 

accident was truly tragic, for the explosion occurred as it was being 

carried in the bomb bay of its Superfortress mothership over Lake 

Ontario. The rocket plane vanished in a fiery red blast that killed its Bell 

*NACA RM-H55G25, “Behavior of the Bell X- 1A Research Airplane during Exploratory 

Flights at Mach Numbers near 2.0 and at Extreme Altitudes,” NACA HSFS, 7 July 1955. Like 

RM-H55A13 (the X-3 and F- 100 stability study), this RM was widely circulated throughout 

industry and was very influential. 

71 
ON THE FRONTIER 

test pilot and another Bell flight crewman. The launch plane returned to 

base, mangled by the blast. On 8 August 1955 it was NACA’s turn, with 

the X-1A. 

The NACA High-speed Flight Station had made only one flight with 

the X-1A before the accident. That day, at 9450 meters and less than 

one minute from launch, the X- 1A’s liquid oxygen tank burst from an 

internal low-order explosion, expelling a shower of debris that fractured 

the canopy of one of the chase planes. NACA test pilot Joe Walker 

scrambled back into the B-29, and the Superfort’s crew began a steady 

descent, anxiously watching the steaming rocket plane. For a while, it 

appeared that they might be able to land; Dick Payne, the X- 1A’s crew 

chief, entered the X- 1A’s cockpit to jettison the remaining fuel. However, 

the blast had also caused the rocket plane’s landing gear to extend, 

making a landing attempt questionable. For over half an hour, the 

Superfortress and its potentially deadly cargo cruised east of Rogers 

Lake, as the NACA flight crew pondered what to do, with Joe Vensel and 

Scott Crossfield offering advice from the ground. But there was no real 

option. Resigned, Vensel radioed Stan Butchart, the B-29 pilot, “Butch, 

you might as well drop it. Pick a good place.” They did, over the Edwards 

bombing range.* The X- 1A entered a flat spin and fell into the desert, 

exploding in an orange ball of flame and starting a small brush fire.g 

And now the task of sorting out the cause began. Walt Williams was 

away fishing in the mountains, so De Beeler formed an accident board 

under his direction, consisting of representatives from the High-speed 

Flight Station, the Air Force Flight Test Center, Bell Aircraft Corporation, 

the Air Force Office of the Inspector General, NACA’s Langley laboratory, 

and the Air Force’s Power Plant Laboratory at Wright-Patterson AFB. 

Fortunately, the X- IB, sister of the X- IA, was available for examination, 

having just returned from Langley where it had been instrumented for 

aerodynamic heating studies. The X- 1A’s wreckage-what was left of 

it-was placed in the HSFS Loads Calibration Hangar, and the X-1B 

wheeled alongside for comparison. Investigators quickly ruled out electrical detonation of fuel vapor (blamed previously for loss of the X- ID), or 

fatigue fracturing of the liquid oxygen tank. The tank pressure regulators were recovered in good condition, ruling out inadvertent overpressurization. The craft’s nitrogen tanks had even survived the ground 

*Subsequently Butchart, Payne, and Walker received the NACA Exceptional Service Medal. 

B-29 crewmen Charles Littleton and John Moise received the NACA Distinguished Service Medal, 

and crewmen Jack McKay, Rex Cook, Richard De More, and Merle Woods received letters of 

commendation. NACA also commended chase pilot Maj. Arthur “Kit” Murray (pilot of the damaged 

chase plane) in a letter from the Committee chairman to the secretary of the Air Force. 

72 
THROUGH MACH 2 AND 3 

impact, and thus could not have triggered the explosion-yet something 

had blown the oxygen tank apart. 

The vital clue was discovered by Donald Bellman of the HSFS staff. 

As members of the NACA board peered into the liquid oxygen tank of 

the X-lB, they noticed a slimy, oily residue coating the bottom of the 

tank. “What’s that?” one of them asked. “Oh,” a Bell representative 

replied, “We have that all the time. We just wipe it out.” Suspicious, 

Bellman gathered up the sludge in small bottles and sent one sample to a 

highly touted laboratory in Los Angeles, another to the Air Force’s own 

chemical laboratory at Edwards. The Los Angeles laboratory returned a 

superficial report stating, in essence, that the residue was a hydrocarbon 

product that had no business being around liquid oxygen. But the Air 

Force’s chemists did a detailed analysis, identifying the substance as 

TCP-tricresyl phosphate, a substance used to impregnate leather. All of 

the destroyed rocket planes-as well as those still flying-had gaskets 

made of Ulmer leather-leather impregnated with a 50-50 mix of TCP 

and carnauba wax. 

Subsequent experiments showed that when compressed between 

flanges and allowed to stand overnight at room temperatures, the TCP 

would separate from the leather and wax, running and pooling as it had 

in the X-1B’s lox tank. Commercial bottled gas experts informed 

Bellman that at high pressures and law temperatures, Ulmer leather 

could be extremely dangerous, exploding at a comparatively low impact. 

As early as 1950- 1951, this information, on the basis of laboratory tests, 

had been known to commercial bottled gas companies. Bellman supervised construction of a test apparatus to drop a 2-kilogram steel bar three 

meters onto lox-soaked samples of Ulmer leather and on frozen drops of 

TCP; the results of 30 tests were 30 explosions.” 

The accident board theorized that when the gaskets compressed 

under pressure, the TCP exuded and ran into all available crevices. In 

the supercold environment of the lox tank, abrupt movements of the 

tank bulkhead or lox tubing could detonate this residue. Reexamination 

of the other rocket airplane explosions found a lot of supporting 

evidence, especially in the location and sequence of the explosions, for 

the Ulmer leather theory. The board’s final report blamed explosive 

gaskets for the loss of the X- 1A and concluded that it could have caused 

the previous explosions as well. Thus the culprit was identified, cause of a 

series of accidents that had cost two lives and one serious injury, the 

destruction of four rocket research airplanes and two launch aircraft, 

and a two-year delay in the first mach 2 flight.” Never again did any of 

the early rocket research aircraft suffer a catastrophic blast. The Air 

Force, anxious to begin flight testing on the more powerful X-2, went 

ahead with renewed confidence on that behind-schedule program. 

73 
ON THE FRONTIER 

NACA, on the other hand, was still frustrated-it had lost yet another 

mach 2 X- 1. The program so carefully planned for the X- 1A had to be 

abandoned, with some portions taken over by the X-1B and others by 

the X-lE, a mach 2 “homebuilt” designed at the High-speed Flight 

Station. These two programs will be discussed subsequently. Meanwhile . the Air Force, as the possessor of the fastest flight research aircraft at the 

lake, the X-2, set its sights on mach 3. 

THE GOTTERDAMMERUNG OF THE x-2 

No program caused the NACA, especially the engineers of the 

High-speed Flight Station, more frustration and disappointment than 

the X-2. It highlighted the terrible effects of underestimating the 

technical complexities involved in developing a radical new aircraft. It 

also highlighted the dangers of succumbing to the pressure to set records 

in the guise of research. The X-2 program was an unqualified failure, 

despite achieving both altitude and speed records. It failed to return any 

of the high-speed aerodynamic heating information anticipated from the 

program. Two aircraft were built; both were destroyed with three 

fatalities. 

The X-2 was the most exotic and complex of the early rocketpropelled research aircraft. Designed for supersonic tests of the sweptwing shape, the plane had an estimated performance in excess of mach 3. 

The first plane designed to withstand the rigors of aerodynamic heating, 

its structure was fabricated from stainless steel and a nickel alloy. To be 

air-launched and propelled by a two-chamber rocket engine, it would 

land on retractable landing skids. Bell had hoped to complete the first 

aircraft in 1948, but construction delays caused by the complex alloy 

structure and problems with its explosion-prone Curtiss-Wright 6’7 000- 

newton (15 000-lb) rocket engine stretched the development program by 

years. 

The ill-fated Bell X-2 rocket research aircraft. 

74 ’ 
* d h r f 

THROUGH MACH 2 AND 3 

As time went on, NACA's interest in the airplane declined markedly. 

By 1953, much of the sweptwing information that the X-2 could have 

provided had already been derived from the Skyrocket. Initial glide trials 

with the first of two X-2s took place in 1952, demonstrating that the 

plane flew well at low speeds (its engine was still not ready for installation). 

Then in 1953 the second X-2 was lost over Lake Ontario with two 

crewmen, delaying the program yet again. Problems with its planned 

electrical flight control system forced a change to a conventional hydromechanical system patterned on that of the F-86 fighter. The sole 

surviving X-2 flew again on another series of glide trials in 1954-still 

lacking its rocket engine-which forced redesign of the landing skids 

and shock-absorbing strut system. At last, the Curtiss-Wright engine was 

ready for installation, and the X-2 arrived back at Edwards in the 

summer of 1955, ready for its powered flight trials. Then the loss of the 

X- 1A and the subsequent accident investigation grounded the X-2 for 

replacement of its dangerous gaskets. 

Management responsibilities for the X-2 lay between the Air Force 

and Bell. NACA participated in some X-2 support research, primarily 

Langley wind-tunnel studies and Wallops rocket-model tests, and the 

RAPP made many recommendations, suggesting unsuccessfully that its 

trouble-prone Curtiss-Wright engine be replaced. By October 1955 the 

Air Force had lost patience with the program and issued an ultimatum: if 

the X-2 did not complete a powered flight before the end of the year, the 

project would be terminated. l2 NACA still retained a little enthusiasm for 

the plane, wanting it for aerodynamic and structural heating studies. The 

X- 1B was making similar studies, but the X-2 could go far beyond the 

X- lB, up to mach 3. Even though the NACA recognized that the X-2 

would soon be overshadowed by the X- 15 then under development, the 

agency still believed that the near-term availability of the plane would 

furnish much information unavailable from other flight testing programs on the heating conditions encountered at mach 3. 

The X-2 completed its first powered flight on 18 November 1955. 

Piloted by Air Force test pilot Pete Everest, it featured brief but not 

damaging fire in the engine bay. Nevertheless, the Air Force ruled the 

test a success, giving the program its reprieve. For various reasons, the 

plane did not fly again until March 1956. During these Air Force trials, 

the plane remained the property of the Bell Aircraft Corporation, which 

did not deliver it to the Air Force until 23 August 1956. Walt Williams 

and his engineering staff, watching patiently from the sidelines, were 

occasionally asked to furnish technical assistance. 

On the advice of the NACA, the Air Force had bought a special 

computer, the Goodyear Electronic Digital Analyzer, which would predict aircraft behavior by extrapolation of results from test flights. This 

would give engineers and pilots some indication of what to expect as they 

75 
c * 

ON THE FRONTIER 

flew higher and faster. NACA had designated Richard Day as the HSFS 

program engineer for the X-2; he helped with the new computer, 

providing equations and motions data. Day routinely briefed project pilot 

Pete Everest and, later in 1956, Iven Kincheloe and Me1 Apt, Everest’s 

replacements. l3 

The simulations confirmed predictions from N ACA wind tunnel 

tests that the X-2 would have rapidly deteriorating directional and 

lateral (roll) stability near rnach 3. Aileron deflection (to roll the plane) 

could lead to an aerodynamic condition known as adverse yaw, followed 

by increasingly rapid rolling until the rolling motions reached a “critical 

roll velocity,” the point where the plane would roll into inertial coupling 

and tumble. During 1956, as Pete Everest moved up in speed, NACA’s 

Dick Day and Hubert “Jake” Drake anxiously watched the directional 

stability curves, compared them to flight data, and urged the Air Force to 

move in smaller increments, not in great leaps of half-a-mach number.14 

In May 1956, Everest achieved mach 2.53, making the X-2 the fastest 

aircraft in the world. By this time, NACA’s patience was running 

somewhat thin; in early June, at a joint NACA-Air Force -Bell meeting 

at Edwards, the NACA representatives requested that the X-2 be 

delivered to NACA sometime between 15 September and 1 October, so 

that the High-speed Flight Station could complete a few flights before 

winter rains flooded the lakebed. The Air Force agreed, stating that the 

service’s program would be “to expand the speed and altitude envelope 

to at least nominal values”-30 000 meters and mach 3.15 Everest came 

close to this on 23July, when he reached 2.87 (3057 kilometers per hour), 

his last flight before moving to a staff assignment in Norfolk, Virginia. 

Following Everest’s final flight, the Air Force momentarily lost 

interest in mach 3 in favor of attaining the craft’s maximum altitude. Test 

pilot Iven Kincheloe flew the plane to 38 470 meters, the first flight above 

30 500 meters. At that altitude, aerodynamic controls were useless. The 

X-2’s behavior in this region of low dynamic pressure (“low q” in 

engineer’s shorthand) pointed to the need for reaction controls. Above 

30 000 meters, still in a ballistic arc, the X-2 began a left bank which 

Kincheloe wisely did not attempt to correct, for fear of tumbling the 

airplane. He experienced less than 0.05 g for approximately 50 seconds, 

a foretaste of weightless spaceflight; popular science writers dubbed the 

pilot the “First of the Spacemen.”” In late August the Air Force had 

taken delivery of the X-2 and then extended its program for an 

additional month (before the plane would be turned over to the NACA), 

announcing the purpose as “to obtain an incremental value of the 

high-speed performance of the X- 2 airplane.”” Into the cockpit stepped a 

new Air Force pilot, Capt. Milburn G. Apt. 

Though he had flown chase on many X-2 missions, Me1 Apt had 

never flown a rocket-powered airplane. He was perhaps the most 

experienced pilot at Edwards on the phenomenon of inertial coupling, 

76 
ir s a 

THROUGH MACH 2 AND 3 

having flown many inertial coupling research flights in the F-100 

fighter. Apt had received computer-based briefings on 29 July and 24 

September, but the briefings had a flaw. The X-2 flights had accumulated useful data only up to mach 2.4. Engineers extrapolated all data 

beyond that, and the predictions were dubious. One study, at a simulated 

mach number of 3.2 at 21 300 meters, showed the aircraft “diverging” 

(going out of control) during lateral (rolling) maneuvers. Being 

extrapolations, none of these studies could be conclusive. On 27 September 1956 Me1 Apt dropped away from the Superfortress mothership in 

the X-2 at 8:49 a.m. His flight plan called for “the optimum maximum 

energy flight path,” one certain, if successful, to exceed mach 3. In a 

postflight question-and-answer session, a senior program official said, 

“Captain Apt was instructed to make no special effort to obtain maximum speed but rather to stay within previous limits and to concentrate 

on the best flying technique possible.”’* Clearly some confusion existed in 

the minds of mission planners. And there was the matter of experience; 

Apt had not even had the benefit of a glide flight in the X-2; his sole 

time in the cockpit was spent in several ground engine runs and posing 

for publicity photographs with Kincheloe. He had been cautioned to 

decelerate rapidly if he encountered stability difficulties and not to make 

rapid control movements above mach 2.7. 

As Apt climbed away after launch, he followed a predetermined 

schedule matching the airplane’s g loading versus altitude, based on 

code numbers radioed from ground radar tracking. He reached high 

altitude, nosed over and dived past mach 3, reaching mach 3.2 (3370 

kilometers per hour) at 20 000 meters. His rocket engine burned for 

another 10 seconds, longer than previously. The flight had been flawless, 

but now victory turned to ashes. Apt began an abrupt turn back for the 

lake. Perhaps he believed the X-2 was traveling slower than it was. Like 

all early X-series aircraft, the X- 2 had lagging instrumentation. The 

cockpit camera film showed the machmeter indicating mach 3 for over 10 

seconds. As the X-2 turned, it started a series of rapid rolls and the 

“critical roll velocity,” an engineering construct, now became a brutal 

reality. The X-2 coupled, tossing Me1 Apt violently about the cockpit, 

knocking him unconscious. Apt slowly came to, tried to regain control, 

then jettisoned the craft’s nose section in preparation to bail out. The 

shock of jettisoning the nose knocked him unconscious again, and before 

he could recover, the capsule plunged into the desert, killing him 

instantly. The rest of the X-2 spun into the desert eight kilometers away. 

Barely three minutes after launch, Me1 Apt had become the first pilot to 

reach mach 3, and then died. Kincheloe’s voice continued on the radio, 

“Mel, can you read me, Mel?”lg 

A valued pilot had died. A research airplane had crashed just as it 

might have begun justifying its development. A record had been set, but 

to little purpose. The accident illustrated the acute need for reliable 

77 
* 0 e 

ON THE FRONTIER 

cockpit instrumentation for high-speed flight research, and this eventually helped spawn the special gyro-stabilized inertial guidance system 

used on the X- 15. Some tried to point to “research accomplishments” of 

the X-2, citing limited heating data acquired from seared samples of 

temperature-sensitive paint-which rocket models could more easily 

have acquired. In reality, its research was nil. Groping for significance, 

the Edwards historian asked one program official, “I imagine the X-2 

program contributed greatly to aeronautical knowledge, didn’t it?” 

“More than ever before,” answered the official, “we appreciate the 

requirement of providing the pilot with the information he needs to do 

his job.”” Back in Washington, the NACA staff fired off a series of 

messages to Walt Williams, fearful lest the High-speed Flight Station had 

condoned the flight. One, from Dryden’s deputy, got right to the point: 

WHAT DOES OPTIMUM MAX ENERGY FLT PATH MEAN 

PD SGND CROWLEY 

The Air Force Flight Test Center issued its accident report in November 

1956; it concluded that the fatal turn at peak velocity had led inevitably 

to coupled motion instability.21 

The loss of the X-2 once again robbed the NACA of a research tool 

just at a time when it might have proved worthwhile. Previously, the 

NACA had lost its planned programs on the X- 1-3 and X- 1A because 

of the gasket explosions. The X-2 fiasco removed the last chance to get 

mach 3 heating data prior to the X- 15. The agency had to make do with 

the X-lB, capable only of approaching mach 2, an unpleasant price to 

pay for a speed record. It was particularly galling because Apt’s flight was 

to have been the last Air Force flight before the X-2 was turned over to 

the NACA. 

The X-2 program was disaster masquerading as research organization, 

and subsequent program reviewers could not ignore the facts. The Air 

Force’s program historian argued that Me1 Apt had certainly needed at 

least one low-supersonic familiarization flight in the X- 2, questioning 

why “a pilot with limited experience like Captain Apt [was] shoved into 

the cockpit of the X-2 on an optimum flight at the last minute.”22 NACA 

would certainly have agreed with his overall conclusion: 

Only one conclusion can be reached and that is that the Air Force in its 

determination to attain a record speed and altitude with the X-2 which it did 

achieve assumed a calculated risk of losing the pilot and the aircraft in the 

process. . . . Fatigue, miscalculations, and poor judgment entered into the 

program at a time when unhurried flights were in order and good judgment 

should have directed and supervised the pr0gram.2~ 

78 
L 

THROUGH MACH 2 AND 3 

“ROUND ONE’S” TWILIGHT YEARS 

The High-speed Flight Station continued flying the two remaining 

rocket research airplanes, the X- 1B and the X- lE, until mid-1958. 

Both assumed some of the tasks envisioned for the lost X- 1A and X-2, 

but they also took on new ones as well. After the Air Force had delivered 

the X- 1B to the High-speed Flight Station in 1954, NACA shipped the 

airplane back to Langley for installation of 300 thermocouples and 

related instrumentation to measure structural temperatures. It had 

arrived back at Edwards in time to assist in the X- 1A accident investigation and did not fly until August 1956, embarking on its heating research 

program the next month. In January 1957, NACA test pilot Jack McKay 

extended the investigation to mach 1.94, bringing the program to a 

conclusion. Project engineers believed the data to be representative of 

heating conditions that could be expected on future mach 2 military 

aircraft. The maximum heating rate experienced was about 1°C per 

second, with a maximum skin temperature of 85°C being recorded on 

the forward point of the nose. Internal heat “sinks” and sources appreciably affected skin temperatures. While the skin next to the liquid oxygen 

tank had a temperature of only 1O”C, that just ahead of the tank was 

50°C. The flight results generally agreed with estimated temperatures 

derived by calculation. This X- 1B study was the first major aerodynamic 

heating flight research study undertaken in the United States, and, alas, 

was a good example of the kind of work the High-speed Flight Station 

had expected from the X-2.24 

Iven Kincheloe’s high-altitude flight in the X-2 demonstrated the 

inadequacies of conventional aerodynamic controls for flight in regions 

of low dynamic pressure. One solution was the installation of small 

reaction-control thrustei jets for maintaining proper vehicle attitude in 

regions of low “q”. In 1956 the High-speed Flight Station began 

researching reaction controls in support of the X- 15 program. Writing 

nearly a decade later, engineer Wendell Stillwell of the HSFS stated: “The 

transition from aerodynamic control to jet control loomed as the most 

difficult problem for this vast, unexplored flight regime.”25 The X- 1B 

offered an ideal testbed for a trial reaction control installation. In 

preparation, HSFS technicians built an iron-frame simulator, dubbed the 

“Iron Cross,” which matched the dimensions and inertial characteristics 

of the X-lB, installing small reaction control thrusters on it and then 

mounting it on a universal joint so that a test pilot could maneuver it in 

pitch, roll, and yaw. NACA’s test pilots “flew” this simulator extensively. 

In November 1957, NACA finished installing reaction controls on the 

X-1B itself, and test pilot Neil A. Armstrong made three flights in the 

plane before it was grounded in the summer of 1958 because of fatigue 

cracks in its fuel tank. NACA subsequently transferred the reaction 

79 
ON THE FRONTIER 

control research program to a Lockheed F- 104 Starfighter; this aircraft 

played a major role in training pilots for the X- 15.26 

The X-1E was the last of the hardy X-1 breed to retire. An 

extensive modification of the NACA’s original X- 1 aircraft, the X- 1E 

had been rebuilt with a low-pressure fuel system and a special low-aspect 

ratio wing having a thicknesskhord ratio of only 4%. Much of the design 

work was undertaken by the High-speed Flight Station staff, which saw 

the craft as an opportunity to get information at speeds above mach 2 on 

this wing configuration-similar to that of the X-3-that the X-3 had 

been unable to obtain because of its inadequate propulsion system. The 

wind had no less than 200 pressure distribution measurement orifices cut 

into it, as well as 343 strain gauges baked into the wing surface for 

structural load and heating research. At one point, after the loss of the 

X-2, NACA engineers Hubert Drake and Donald Bellman proposed 

boosting the X- 1E’s engine performance to enable the plane to reach 

mach 3, but NACA opted to wait for the X-15 instead. The X-1E 

suffered a hard-luck flight research program, experiencing two landing 

accidents, one of which severely damaged the airplane. It did complement the heating research undertaken by the x- lB, but by the time of 

its flight trials, the Lockheed F-104 with a generally similar wing 

configuration was already flying and could more easily acquire data at 

mach 2. The rocket aircraft required time-consuming preparations; as 

research engineer Gene Matranga recalled, “We could probably fly the 

X- 1E two or three times a month, whereas Kelly Uohnson] was flying his 

F- 104s two or three times a day into the same flight regimes, so it really 

didn’t make sense for us to be applying those kind of resources to [obtain] 

that kind of inf~rmation.”~’ The X- 1E completed its last NACA flight in 

November 1958. It is now permanently exhibited in front of the Dryden 

center, perched at a jaunty angle. 

“ROUND ONE” IN RETROSPECT 

The conclusion of “Round One” in 1958-1959 brought the era of 

the supersonic breakthrough to a close. Figure 1 illustrates the comparison between rocket research aircraft, military fighter prototypes, and 

military fighters in service. As can be seen, the X-series never led the 

prototypes by less than 0.6 mach; by 1956, this had increased by a whole 

mach number. The differences between X-series performance and 

aircraft in service at the time is even more pronounced (for example, the 

X- 1A vs. F-86F Sabre of 1953). 

Figure 2 places the rocket research aircraft program within the 

context of speed trends throughout aviation history. The figure illustrates the interesting relationships among different growth curves. 

Notice that as piston-engine technology approached its limits a new 

technology revolutionized the field-the jet engine. The rocket research 

80 
e \* e’ c 

3.5 

3.0 

2.5 

2.0 

1.5 

1.0 

.5 

- 

- 

- 

- 

- 

- 

- 

THROUGH MACH 2 AND 3 

x-2 

X-1 A 

F-1 OOA 

P-80A a Research aircraft 

o Prototype fighters 

n Service fighters 

Illllllllllll~ 

1946 47 48 49 50 51 52 53 54 55 56 57 5a 

Year 

Figure 1. Leader-follower relationship between research aircrafi, military fighter protoqpes, 

and military fighters in service. 

aircraft curve exhibits rapid growth over a short period of time. The jet 

fighter curve is a classic example of the “S” or biological curve: slow 

progress initially (“infant problems”), a period of very rapid growth 

(from mach 1 to mach 2), and then, beginning just beyond mach 2, the 

rate of development slows because of a variety of factors, including 

propulsion efficiency, aerodynamic and heating constraints, cost of such 

complex systems, and questionable mission utility above mach 2. Several 

leader-follower relationships are illustrated: piston military fighters led 

piston transports, jet fighters led jet transports (a continuance of the 

earlier trend), and the rocket research aircraft led the development of jet 

fighters.28 Significantly, the growth curve for the rocket research aircraft 

is “open-ended’; beyond these Round One vehicles was the mach 6 

X-15; beyond it the logical successor system was some form of liftingreentry spacecraft such as the present-day Space Shuttle. The Round 

One rocket aircraft, besides contributing markedly to the acquisition of 

informafion on supersonic flight, were thus pointing toward manned 

suborbital and orbital spaceflight as well. 

Figure 3 indicates the life-cycle histories of the Round One aircraft, 

including development time along with active flight status. The relatively 

81 
ON THE FRONTIER 

4480 

4160 

3840 

3520 

3200 

2880 

2560 

2240 

- 

- 

- 

- 

- 

- 

- 

- 

Rocket 

research 

aircraft i 

Jr 

fighters 

P 

Jet 

transports 

1- 'gnte~~4ransports 

1910 1920 1930 1940 1950 1960 

Year 

Figure 2. Aircraft peformance by aircraft category. 

short development cycles for such successful aircraft as the original X- 1 

series forms an interesting comparison to such disappointing programs 

as the X-2 and X-3. 

The Round One aircraft, including both the rocket research 

aircraft and the configuration explorers, investigated a variety of topics 

and problems. Walter Williams and Hubert M. Drake of the High-speed 

Flight Station tabulated these into four broad areas: aerodynamics, flight 

loads, stability and control, and operations: 

Aerodynamics 

Validation of transonic tunnel design 

Interpretation of tunnel testing data 

Aerodynamic heating at supersonic speeds 

Lift and drag studies 

Inlet and duct studies 

Load distribution 

Effect of wing sweep upon gust loads 

Gustiness at high altitudes 

Buffeting 

Flight loads 

82 
THROUGH MACH 2 AND 3 

x-1 #I 

x-1 #2 

x-1 #3 

0-558-1 #I 

D-558-1 #2 

0-558-1 #3 

D-558-2#1 

0-558-2#2 

D-558-2 #3 

X-1A 

X-1B 

X-1D 

X-1E 

x-2#1 

X-2#2 

x-3 

x-4#1 

X-4#2 

- = I 

- 4 (to X-1 E) * 

-- 

-

- 

- A * I 

- ,- -- - - - -G-C-l 

- - 1 

- __ I 

- r- 

- r * -r 

- 0 a -- 

- r - r 

- 

- - 0 

- -r 0 

- ^^ 

-- 

- I- “ I 

m I 

* m I 

- 

- c 

- c I 

1945 46 47 48 49 50 51 52 53 54 55 56 57 58 

Year 

Fagure 3. Comparative lfe cycles for “Round One” aircraft. 

Aeroelastic effects 

Effect of stability reduction upon flight loads 

Longitudinal control 

Blunt trailing edge control surfaces 

Alleviation of pitch-up by wing devices 

Effect of principal inertial axis upon lateral stability 

Exhaust jet impingement effects upon stability 

Inertial coupling 

Directional instability 

Reaction controls 

High-speed flight exploration 

Speed loss in maneuvers 

High-altitude problems 

Pressure suit research and use 

Airspeed measurement 

Variable wing-sweep operation2’ 

Stability and control 

Operations 

83 
ON THE FRONTIER 

The diverse range of research areas offers yet another example of 

the serendipitous character of the Round One aircraft. Conceived largely 

for aerodynamic and loads research at the speed of sound, they contributed markedly in other areas as well, influencing subsequent aircraft 

design practice-use of vortex generators, all-moving horizontal stabilizers, 

placing the horizontal tail low, increasing the size of vertical fin surfaces 

for high-speed flight, alleviating pitch-up by a variety of wing leading 

edge devices, to name just a few. Their development acted as a “forcing” 

function, encouraging the development of improved ground research 

methods, notably the transonic slotted throat tunnel.30 And, of course, 

there was the very real psychological benefit accruing from removing the 

“sound barrier” as a fixation from the minds of engineers. 

In some respects the Round One aircraft were disappointing. Maintenance demands limited most rocket research aircraft to an average of 

one or two flights per month. Then there is the sad chapter of the ex- 

”.., -:? *, ... ,.“.*..I 

These personnel members and this equipment were used by the NACA High-speed Flight 

Station to support oneflight of the NACA 0-558-2 Skyrocket. Note the two Sabre chase 

planes, the modified B -29 launch aircrafi, and the profusion of ground support equipment, 

including communications, tracking, maintenance, and rescue vehicles. Research pilot A. 

Scott Crossfield stands in front of the Skyrocket. 

84 
THROUGH MACH 2 AND 3 

plosions, which robbed the NACA, at critical moments, of the X- 1-3 

and the X-1A. The X-2 story of delay and misuse, and the sad tale of 

the X-3 and its propulsion problems are classic examples of programs 

that got out of hand. They pointed to the need for greater coordination 

and cooperation between the NACA, industry, and the military services. 

The complexities of X- 15 development provided an opportunity to 

exercise this tighter control, and the rising costs of aeronautical research 

and development implicitly dictated that the days where a program like 

the X-2 would be allowed to continue were at an end. 

Round One was a flight research program; as such, it was almost 

exclusively the accomplishment of the NACA High-speed Flight Station 

under the direction of Walter Williams, with the support of Hartley Soul6 

as research airplane projects leader and Hugh Dryden as NACA director 

of research. The High-speed Flight Station had used the Round One 

airplanes to undertake and consolidate the supersonic breakthrough. By 

1959, as the early X-series passed into eclipse, all eyes at Edwards turned 

to the sleek, black X-15. Round One had been a success, and the 

production aircraft then aloft, from passenger-carrying jet transports to 

mach 2 military fighters, were the beneficiaries of its technical bounty. 

85 
c F 
5 

Testing Service Aircraft: 1953- 1959 

The National Advisory Committee for Aeronautics had a long 

history of assisting the military services and other government agencies 

on research to new aircraft development projects. As early as the 1920s, it 

was not at all uncommon for NACA to participate in flight tests of 

military aircraft. Indeed, on occasion, NACA pilots flew test flights for 

the contractor (a good example being Langley’s Bill McAvoy, who flew 

some of the hazardous spin and dive tests on the XF3F for Grumman 

and the Navy). During World War 11, NACA had joined in many flight 

research investigations related to improving the combat potential of 

American military aircraft such as the Republic P-47 fighter, the Curtiss 

SBZC dive bomber, and the North American P-51 Mustang. Of course, 

these aircraft, and many others as well, were also studied extensively in 

NACA wind tunnels, a traditional form of agency support to the military 

and industry. 

This cooperative role continued after World War I1 as well, encouraged by several factors including an official Air Force policy of “concurrency” 

testing whereby a large number of initial production-model aircraft were 

tested at laboratories and field sites around the country, including 

NACA, to accelerate the testing process, reducing the chances of encountering problems that might arise should an experimental design be 

committed to production on the basis of only a few tests on prototypes. 

Further, with the new generation of transonic and supersonic fighter and 

bomber aircraft drawing on more new technology than ever before, there 

was greater need to deliver pre-production or early production models to 

NACA for evaluation and uncovering of possible defects. After completing the requested projects for the services or manufacturers, NACA 

either returned the aircraft or kept them in NACA-NASA service, 

flying on a variety of “research opportunity” tasks, often for many years. 

Though service aircraft appeared at various NACA laboratories during 

the 1950~~ the major focus of such research was, not unnaturally, the 

High-speed Flight Station at Edwards, since Edwards constituted the Air 

Force’s center for flight research. 
ON THE FRONTIER 

EARLY WORK 

As early as 1950, the NACA-Edwards station had participated in an 

Air Force development program when station engineers provided 

assistance to the service and the Republic aircraft company on the 

XF-91 experimental interceptor. But the XF-91 was a radical departure from conventional aircraft design for the day; thus NACA research 

on the craft could be regarded as motivated as much by the desire to 

conduct pure research as by the need to assist the military service. In 

1952, however, the NACA station at Edwards made a major contribution 

to saving a military fighter program in serious trouble, the Northrop 

F-89 interceptor. 

The F-89 was a high-priority air defense program. In the early 

months of 1952, six F-89s lost their wings in flight, With more than 

a thousand built or on order, the Air Force faced a serious crisis, for the 

F-89 was considered a major element in the North American air defense 

structure. At the request of both the contractor and the Wright Air Development Center, the NACA-Edwards station entered the investigation. 

Since the aircraft had obviously suffered structural failures, Walt Williams loaned a NACA team to Northrop to determine the F-89’s inflight 

loads. The NACA team installed strain gauges on an experimental F-89 

and then studied the data acquired from test flights. As a result, Northrop discovered a serious weakness in the wing structure and redesigned 

the structure to strengthen it. The F-89 subsequently went on to a long 

and useful service career, and the NACA’s assistance on the program 

enhanced the agency’s reputation among the military and industry flight 

testing community. 

NACA-Edwards followed the F-89 experience with a major investigation of another Air Force aircraft, the B-47 jet bomber. Unlike the 

earlier case, however, the B-47 was not in difficulty. Rather, the NACA 

had asked for the loan of one of the planes to study aeroelastic wing 

flexing. The B-47, a shoulder-wing monoplane, had six podded jet 

engines and a very thin sweptwing. An airplane with a large, thin, flexible 

wing could have peculiar aerodynamic and structural load responses as a 

result of interactions between wing and tail deflections and transonic 

airflow changes. The field of aeroelasticity, while not new, took on added 

importance with the large sweptwing aircraft then under development or 

in production, especially the B-52, an urgent defense program, and a 

Boeing tanker-transport design that eventually spawned the KC- 135 

tanker and the 707 airliner. Two NACA laboratories had an interest in 

the B-47; Langley wished to study the impact of aeroelasticity upon 

structural loads and Ames the impact of aeroelasticity upon dynamic 

stability. Operation of the aircraft from either center was dubious 

because of runway length. Accordingly, the RAPP sent it to the NACA 

88 
TESTING SERVICE AIRCRAFT 

station at Edwards, where it flew from May 1953 to 1957. NACA’s B-47 

testing revealed some serious design deficiencies; buffeting problems 

limited the plane to speeds no greater than mach 0.8 and certain lift 

values. In late 1953, NACA requested that the Air Force provide a B-52 

as soon as possible, so that the research gathered with the B-47 could be 

extended through mach 0.9 + and up to 15 000 meters in altitude. NACA 

never got the B-52, but did secure permission to instrument a B-52 

being flown by Boeing; a company-sponsored loads investigation, including the special maneuvers called for by NACA, then gathered much of 

the data NACA wanted. The B-47 testing resulted in reports prepared 

jointly by the HSFS, Ames, and Langley laboratories that gave engineers 

and design teams around the country access to reliable information on 

the dynamic behavior and response characteristics that could be expected 

of large, flexible sweptwing airplanes2 

The High-speed Flight Station later continued its large jet aircraft 

studies using a Boeing KC- 135 tanker, starting with one aircraft loaned 

by the Air Force in 1957. But flight tests were suspended after a 

near-disastrous midair collision between the plane and a jet trainer from 

the Air Force Test Pilot School. The KC- 135, piloted by Stan Butchart, 

staggered down to a safe landing on Rogers Lake but the trainer, whose 

civilian pilot apparently never saw the transport, crashed, killing the 

student. The Air Force delivered a second KC- 135 on ninety-day loan; 

it completed a number of flights before being returned to the service in 

1958. The KC- 135 flights had been requested by the NACA Subcommittee on Flight Safety, in response to a plea from the Civil Aeronautics 

Administration (CAA). The CAA needed information that might be 

useful in writing regulations on cloud ceiling and minimum landing 

approach visibility for the new generation of jet transports then under 

development. NACA research on the plane evaluated high-altitude 

cruise performance, landing approaches including “instrument only” 

conditions, and how the jet’s wing spoilers affected its glide path during 

landing approaches. 

NACA AND THE “CENTURY SERIES” 

The High-speed Flight Station’s major service testing activities 

supported the Air Force’s “Century Series” of fighter and interceptor 

aircraft. Table 2 lists those evaluated at the HSFS from 1954 onward. 

The F- 100, F- 102, and F- 1.04 initially were sent to HSFS in support of 

the military development of those aircraft. The F-101 and F-105 

appeared at the lake only briefly, so that pilots could familiarize themselves with the characteristics of those aircraft. The F- 107 program was 

an abortive attempt by a contractor to develop a mach 2 fighter-bomberthe F- 105 won the production order; NACA acquired the F- 107s to 

89 
ON THE FRONTIER 

Table 2 

Century Series Aircraft 

Aircraft Speed 

(mach) 

Period 

North American F- lOOA 

North American F- lOOC (#1) 

North American F- lOOC (#2) 

McDonnell F- lOlA 

Convair YF- 102 

Convair F- 102A 

Lockheed YF- 104A” 

Lockheed F- 104A (#1) 

Lockheed F- 104A (#2)b 

Lockheed F- 104B‘ 

Republic F- 105B 

North American YF- 107A (#1) 

North American YF- 107A (#2)d 

1.3 

1.4 

1.4 

1.7 

0.98 

1.2 

2.2 

2.2 

2.2 

2.2 

2.0 

2.0 

2.0 

~ 

1954- 1960 

1956- 1957 

1957- 1961 

1956 

1954- 1958 

1956- 1959 

1956- 1975 

1957- 1961 

1959- 1962 

1959- 1978 

1959 

1957- 1958 

1958- 1959 

“Completed 1439 research missions in a 19-year career. 

bLost in accident; pilot safe. 

CTransfer from NASA Ames. 

dLost in accident; pilot safe. 

study some of their design features in support of the XB-70 and X- 15 

efforts. 

During the early 1950s, the Air Force’s procurement policy stressed 

“concurrency” testing. This concept was formalized into the so-called 

Cook-Craigie Plan, after Generals Laurence 6. Craigie and Orval R. 

Cook, the deputy chiefs of staff for development and materiel. CookCraigie assumed that if a design appeared to warrant production, then a 

relatively large number of prototype aircraft should be built-say , 30 to 

40-tested extensively, and the changes incorporated on newly emerging 

production aircraft. This avoided the time delays that might be expected 

if a few prototypes were refined extensively and then the design was 

committed to production. In actual practice, Cook-Craigie proved expensive, 

prone to cause problems in “configuration control” of production 

models, left large numbers of early production aircraft having little 

relationship in systems or combat capabilities to later production models, 

and was as time-consuming as the older method of prototype evaluation 

followed by production. One of Cook-Craigie’s strengths, however, was 

its endorsement of concurrency testing. Typically, various models of a 

new design were assigned to weapon testing, engine testing, systems 

testing, flight (aerodynamic) testing, and the like. As a result, NACA 

90 
TESTING SERVICE AIRCRAFT 

received prototypes of new service aircraft for its own evaluations in 

support of the Air Force development effort. 

In 1954 the first two of the Century Series aircraft arrived at the 

High-speed Flight Station, the F- lOOA and the YF- 102. The F- 100 

was a supersonic aircraft having a low tail and a sharply swept wing 

mounted on a long, rakish fuselage. The YF-102 was basically an 

enlarged XF-92A delta. Whereas the F- lOOA was an early production 

airplane, the YF-102 was a pre-production model of a proposed Air 

Force interceptor. NACA, the Air Force, and the manufacturer already 

knew from wind tunnel tests that the YF- 102’s configuration rendered it 

incapable of meeting the interceptor performance specification, which 

called for supersonic speed. Even as the High-speed Flight Station 

acquired the YF- 102, Convair was busily redesigning the airplane on the 

basis of the area-rule principle developed by Langley’s Richard Whitcomb 

to give it supersonic performance. While HSFS personnel were interested in using the YF-102 to extend the data on delta performance 

already derived by the XF-92A, they eagerly awaited the area-ruled 

version of the plane (the F-l02A), which eventually arrived at the 

station in 1956. In any case, the YF-102 soon took a back-seat to the 

F- lOOA at Edwards, because the F- lOOA program suddenly encountered serious difficultie~.~ 

A series of mysterious crashes of F- lOOA fighters in 1954 claimed 

the lives of several airmen, including George Welch, North American’s 

chief test pilot. His F-100A had suddenly yawed more than 15” and 

broke up while making a rolling pullout from a dive at supersonic speeds. 

The Air Force had evidently placed the F-lOOA in production too 

quickly; Pete Everest, the service’s project pilot on the F-100, had 

recommended that it be modified to overcome supersonic directional 

stability problems. He was overruled at Air Force Headquarters, following a series of evaluation flights by fighter pilots of the Tactical Air 

Command. The fighter “jocks” were not trained test pilots and only saw 

the F- 100 as a big improvement in performance over the older F-86s 

they had been flying. Now his report came back to haunt those who had 

committed the new fighter to ~ervice.~ The Air Force, with hundreds of 

the new planes on order, had no choice but to ground the aircraft until 

investigators could find out what had happened and modify the design. 

Gen. Albert Boyd, commander of the Air Force Air Research and 

Development Command, detailed a senior officer on his staff to meet 

with Walt Williams of the HSFS to get the NACA’s ideas on the crisis.6 

Williams and several NACA engineers, including Joseph Weil and 

Gene Matranga, met with Air Force and North American representatives 

and mapped out a research program. Up to this time, NACA had been 

primarily concerned with evaluating the F- 100’s general stability and 

control; but now, in light of the station’s concurrent experience of 

91 
3 

ON THE FRONTIER 

violent inertial coupling with the X-3, the engineers decided to study 

not only the F- 1OOA’s directional stability problems but roll coupling 

tendencies as well, since the latter had been identified as the cause of one 

of the crashes. North American already had an idea for a fix: enlarge the 

area of the craft’s vertical fin and add more area to the plane’s wing tips. 

Under NACA and Air Force pressure, the cbmpany cut its planned 

delivery schedule for the larger tail from over 90 days to just 9 days, a 

measure of how urgently correcting the F- 100’s problems was viewed. 

Williams’s engineers went to Langley laboratory to run a computer 

simulation of the F- 100’s behavior-the first such simulation done by 

the HSFS-in conjunction with William Phillips, NACA’s acknowledged 

expert on coupled motion instability. The simulation confirmed the 

F- 100’s dangerous directional stability and roll coupling problems; one 

NACA engineer termed its directional stability characteristics as “damn 

poor.” From October 1954 through December, HSFS pilot Scott Crossfield 

flew NACA’s F-100A on a series of flights defining the coupling 

boundaries of the airplane. Williams reported to the RAPP on the results 

of one flight with the plane in its original (small fin) configuration: “a 

violent divergence in pitch and yaw occurred on the F-100A airplane 

during an abrupt aileron roll at a Mach number of 0.70 and an altitude of 

[4800 meters] in which a negative load factor of 4.4 g and a sideslip angle 

of 26” were reached.”’ Had a sideslip of that magnitude occurred at 

supersonic speed, the negative load factor would have multiplied and the 

aircraft probably would have disintegrated. 

At the suggestion of both Williams and North American, NACA 

added a larger vertical fin to the plane in December 1954, adding 10% 

more surface area. Eventually -North American installed an even larger 

fin, having 27% greater area, as well as wingtip extensions, and the F- 100 

series went on to a long and distinguished service life. The F-100 data 

were incorporated in the same research memorandum (RM-H55A 13, 

February 1955) that covered the X-3’s experience, a warning not to 

underestimate the difficulties that could be expected with airplanes having 

insufficient tail area combined with long fuselages and narrow wing planforms. NACA later used the F-100A for a variety of center research 

projects. The center evaluated the behavior of a pitching motion damper 

system on the first F- lOOC received in 1956. As expected, the damper 

further increased the plane’s resistance to coupling. The other F- lOQC 

arrived at the center in 1957, and was used for general research support, 

including chase flights and pilot proficiency flights.8 

In contrast to the F- lOOA experience, the High-speed Flight 

Station’s research on the YF- 102 was more prosaic. Williams’s engineers 

had more interest in the definitive F- 102A just around the corner, and 

thus used the YF-102 primarily to extend the data acquired on the 

basically similar XF-92A. Station engineers did a complete drag survey of 

92 
c 

TESTING SERVICE AIRCRAFT 

NACA’s workhorse North American F-IOOA Super Sabre engages in inertial coupling 

studies. 

the airplane, especially under various conditions of lift, this information 

greatly assisting researchers interested in correlating results taken from 

flight testing with results from wind tunnel tests of the configuration. 

The results constituted an effective measure of the accuracy of the wind 

tunnel findings for aircraft design prediction. The YF- 102 did experience some inertial coupling tendencies, the first encountered on a delta 

airplane, but not as serious as with the F-100. NACA tested the 

production F-102A the agency received in 1956 so that researchers 

could compare differences in drag between two generally similar 

configurations, one having area rule (the F- 102A) and the other lacking 

it. As the 1950s drew to a close, NACA sought information on the 

low-speed approach and landing characteristics of unpowered delta wing 

aircraft, information applicable to the design of future winged spacecraft 

such as the “Round Three” Dyna-Soar. Deltas have peculiar low-speed 

and approach characteristics, including high induced drag, and their 

combined ailerons and elevators (elevons) work under a disadvantage: 

deltas require so much elevon deflection during landing approaches that 

they have very little available elevon “travel” left for good lateral control. 

This limitation could seriously compromise safety during the landing 

approach of a delta-wing spacecraft, especially one having the inherent 

performance limitations imposed by reentry design constraints (i.e., 

sinking like a rock). Before NASA retired the F-102A in 1959, test 

93 
R r: Q e 

ON THE FRONTIER 

pilots Jack McKay and Neil Armstrong flew a series of landing approaches under various lift-to-drag and power conditions, in preparation 

for the ill-fated Dyna-Soar pr~gram.~ 

The third Century Series program to get under way at the HighSpeed Flight Station involved the Lockheed F- 104, an airplane having a 

configuration generally similar to the Douglas X- 3. The program began 

in 1956, the start of an association with this hot fighter that continues 

nearly three decades later. An alluring mach 2 design, the F- 104, with 

its high T-tail, long fuselage, narrow wingspan, and troublesome J79 jet 

engine, posed numerous challenges. The long, pointy configurationpublic relations flacks dubbed the F-104 the “Missle with a Man”- 

promised to give roll coupling problems, and the tail hinted ominously 

at pitch-up, though Lockheed designed a stick shaker and “stick kicker” 

into the controls to prevent an unwary pilot from getting into pitch-up 

difficulties. Both these areas, of course, were ones in which the NACA 

had a vital interest. The Research Aircraft Projects Panel had sought an 

F-104 for the Edwards station since 1954; in late summer of 1956, the 

station received a pre-production YF- 104A.” 

The company and service flight-test program on the F- 104 did 

not go at all smoothly, largely because of powerplant problems and 

equipment failures; it eventually took twice as long as expected, with a 

number of accidents and incidents, some causing fatalities. At one point, 

Lockheed had lost all its instrumented test airplanes; NACA’s YF- 104A 

was the only instrumented airplane left. The Air Force asked for its 

return, but NACA countered with the proposal that NACA run the 

Lockheed test program on the YF airplane, using NACA pilots. Lockheed 

and the Air Force agreed, and the roll coupling study began in May 1957. 

NACA engineer Thomas Finch was detailed to work with the Lockheed test 

team and the company’s aerodynamicists on analog studies of the F- 104‘s 

expected rolling characteristics to predict what might happen in flight, 

while NACA test pilot Joe Walker flew the trials. Over the next nine 

months, the station’s YF- 104A completed more than 60 roll investigations, 

which showed the aircraft to be generally acceptable. Flight test results 

and Finch’s analog studies indicated that transonic and supersonic rolls 

near zero g “entry” conditions could lead to autorotation, a tendency for 

the plane to continue rolling despite the pilot’s applying corrective 

aileron, with accompanying pitching and yawing motions. Finch recommended that if this occurred the pilot use the stabilizer to damp out any 

tendency of the plane to couple. NACA further recommended that 

Lockheed limit the aileron’s “travel” (displacement) at transonic and 

supersonic speeds, only permitting “full” aileron “authority” with the 

plane in the low-speed landing gear-and-flaps-down configuration. This 

confirmed impressions at Lockheed, and the company built mechanical 

limits into the plane, added a yaw damper, and put cautioning notes in 

94 
s c c * B * 

TESTING SERVICE AIRCRAFT 

NACA’sfirst Lockheed Staqighter, the YF-l04A, flies for NASA with an experimental 

test installation to measure base drag. 

the plane’s operational handbook.” Wary pilots still treat the F- 104 with 

caution. * 

The NACA and NASA later flew the YF-104A on a variety of 

research tasks. Equipped with reaction controls, it flew as a trainer for 

X- 15 pilots. It performed other special aerodynamic investigations, such 

as a boundary-layer-noise research program for Ames Research 

Center, before being retired in 1975. While NACA’s program with the 

YF- 104A constituted the station’s major early involvement with the 

F-104, the station also flew three other F-104s acquired later-two 

F- 104As and a two-seat F- 104B from Ames-on a variety of research 

tasks including tests of the Mercury spacecraft’s drogue parachute and 

studies of boundary layer formation transition from laminar (smooth) to 

turbulent flow. The center acquired a number of F-104s in the 1960s 

and 1970s for flight research. 

In contrast to the F-100, F-102, and F-104 programs, NACA’s 

involvement with the F- 107 did not involve support of a major defense 

production program. Rather, the F- 107 was what Williams was fond of 

referring to as a “target of opportunity,” an aircraft possessing some 

interesting features that NACA wished to examine in detail. 

The F- 107 started out as a “growth” version of the F- 100, with an 

estimated mach 2 f speed and some radical design elements. It featured a 

large inlet located above the fuselage, a very sophisticated stability 

*There is a popular tale around Dryden of a local well known former naval aviator up in one of 

the two-seat F- 104s who exuberantly initiated a rapid roll far above mach 1, only to have the NASA 

pilot wrench the stick away with an oath, exclaiming “Not in this airplane you don’t!’’ 

95 
I 1 * 

ON THE FRONTIER 

augmentation system, and an all-moving vertical fin. The inlet and the 

fin designs were what interested NACA. After the F- 107 lost out to the 

F-105 for a major Air Force production contract, the NACA acquired 

the first and third YF- 107s built. The first proved mechanically unreliable and completed only 4 flights before NASA grounded it. The third 

completed 40 flights during 1958 and 1959 before being destroyed in a 

takeoff accident, fortunately without injury to the pilot, Scott Crossfield. 

During this time, the engineers at the High-speed Flight Station modified it with a so-called sidestick flight control system, to gain experience 

using such a system, which was planned for the upcoming X-15 

program. On the basis of F- 107 flight testing, North American refined 

the design of the sidestick planned for the X-15, and the designated 

X- 15 test pilots gained experience with such a system before having to 

try it out in the actual X-15 itself. The sidestick program was NACA’s 

major accomplishment with the craft. The proposed inlet and fin studies 

went by the wayside after the retirement of the first F-107, in part 

because the complex inlet, with its movable inlet ramps and variable inlet 

control, caused so many problems that technicians were eventually forced 

to fix the inlet into a position that limited the plane to a maximum speed 

of mach 1.2.’* 

AN ASSESSMENT 

NACA’s assistance to the Air Force and industry on the F- 100 and 

F-104 contributed significantly to ensuring that both were safe and 

effective combat aircraft. The agency’s program on the YF- 102 and 

F-102A was less important in this regard, but offered an excellent 

opportunity to evaluate the accuracy of wind tunnel predictions against 

full-scale data taken from flight testing, and also to compare the direct 

benefits of Whitcomb area-ruling on an aircraft’s configuration. The 

wind tunnel predictions and expected benefits of area-ruling were 

confirmed during tests. The F- 107 helped X- 15 development move 

smoothly along, giving confidence in the sidestick flight control system. 

For the most part, HSFS research on service aircraft took a definite 

second place to research on the X series; the only exception came during 

the F- 100 crisis. Also, toward the end of Round One, research on service 

craft picked up, in part because after 1955 the HSFS had more time to 

invest in them. Though this could smack of “make-work,” in fact many of 

these new craft had features of interest that did not appear on the 

X series. They included innovations such as the all-moving vertical fin on 

the F- 10’7 and complex stability augmentation systems. Generally, as 

soon as the High-speed Flight Station had finished with the servicerelated testing of the craft, the engineering staff would set to work on a 

program related more to NACA interests, such as reaction control stud96 
TESTING SERVICE AIRCRAFT 

ies with the YF-104A. Williams and his engineers, in pursuit of their 

larger mission of advancing supersonic and hypersonic research, consistently sought to place the testing of service aircraft within not only the 

framework of military and industry needs, but also within NACA’s 

interests in high-speed research, for example the low-speed ground 

approach studies of the F-102A in support of the “Round Three” 

Dyna-Soar. This often led to novel proposals and research trips far from 

the desert. Williams once advocated installing ramjets on the wingtips of 

a Lockheed F- 104A to acquire information that could benefit the design 

of supersonic ramjets; despite interest from the Lewis engine laboratory 

and the Air Force’s Air Research and Development Command, the 

project died for lack of other support. Because the X- 15 had a so-called 

“rolling tail”-the tail surfaces functioned both for pitch and roll control, 

as well as for directional control-Williams and a test team journeyed to 

France to study a French airplane having such a feature, the Sud-Ouest 

Trident experimental interceptor. Test pilots Joe Walker and hen Kincheloe 

flew the craft (both were designated pilots for the X-15) to become 

familiar with the performance and effectiveness of such a configuration. 

The experience gave NACA added confidence in the capabilities of such 

a design feature for controlling the X- 15.13 

Flying these service aircraft was often as potentially hazardous as the 

regular X series. On the first flight of the NACA F-100A, Scott 

Crossfield had to make a powerless “deadstick” landing following an 

engine fire warning, something North American’s own test pilots doubted 

could be done, for the early F- 100 lacked flaps and landed “hot as hell.” 

Crossfield followed up the flawless approach and landing by coasting off 

the lakebed, up the ramp, and then through the front door of the NACA 

hangar, frantically trying to stop the plane which had used up its 

emergency brake power. Crossfield missed the NACA X fleet, but 

crunched the nose of the aircraft through the hangar’s side wall. Chuck 

Yeager then proclaimed that while the sonic wall had been his, the 

hangar wall was Crossfield’s. ’* Test pilot Milt Thompson had a close call 

in one of the F- 104As when one of its flap actuators failed, causing only 

one flap to lower. The F-104A began rolling crazily, but Thompson 

fortunately was at high altitude. He stayed with the plane through four 

rolls of increasing rapidity and coupling tendencies, then ejected. On the 

ground, observers heard Thompson radio “It’s going!” Edwards tower 

reported smoke in sight on the bombing range, but no parachute. “The 

gloom was so thick,” one engineer recalled, “you could cut it with a 

knife.” Meantime Thompson landed in the desert, gathered up his 

’chute, and flagged down a pick-up truck for a ride back to the center 

before lunchtime.’5 

After 1958, NASA’s involvement with service aircraft testing at the 

agency’s Edwards center was greatly reduced. This stemmed from 

97 
ON THE FRONTIER 

various causes. The NASA Flight Research Center, as the High-speed 

Flight Station had been renamed in 1959, was heavily committed to the 

X- 15 program, so the engineering staff lacked the manpower, resources, 

and time to become involved with other projects.* Changes in the 

military’s procurement of aircraft also played a role. Military aircraft 

acquisition and development declined; by 1960, the aircraft that America 

would rely upon for its defense and with which it would go to war in 

Southeast Asia were in service or under development; there was less for 

NASA to do in service-related testing,just as there was less for the Air 

Force as well. In effect, the services simply stopped building new 

airplanes for a while. 

There were also changes in the procurement policy as well. The idea 

of building a number of prototypes and pre-production machines and 

testing them widely was replaced by heavy reliance upon paper studies 

and proposal analysis-“read before buy” rather than “fly before buy.” 

This questionable practice also came to an end at the close of the 1960s, 

when the pace of acquisition stepped up. Then FRC again actively 

supported military aircraft projects with flight testing. 

Symbolically, the High-speed Flight Station’s activities on service 

testing completed the cycle of NACA involvement in the early era of 

supersonic flight. In the 1930s and early 1940s, engineers on the ground 

had generated the concept of a transonic and supersonic research aircraft 

program. In the late 1940s, a specialized NACA facility had been created 

and the research was successfully undertaken. In the 1950s, the frontiers 

beyond mach 1 were explored with a variety of instrumented, piloted 

research tools. And then, using much of the information derived by 

NACA ground and flight testing, manufacturers and the military services 

created a new generation of turbojet-driven combat aircraft and placed 

them in service, with the NACA Edwards station (and other NACA 

laboratories around the country) offering the military the traditional 

NACA support. Supersonic flight had gone from the theoretical, to the 

experimental, to the practical. The next frontier was space. 

*The FRC‘s heavy emphasis on the X-15 was perceived in some quarters as evidence that the 

“single-mission” center could be closed down following the X- 15 program. This perception actually 

led to a congressional proposal to close the center in 1965, as will be discussed. 

98 
4 * 

I1 

R * 

Into Space: 1959- 1981 

0 

L 

6 

The X-15 Era: 1959-1968 

On 1 October 1958, High-speed Flight Station employees Doll 

Matay and John Hedgepeth put up a ladder in front of the station 

building at the foot of Lilly Avenue and took down the NACA emblem, a 

winged shield, from over the entrance door. NASA had arrived in the 

desert, bringing with it a new era of space-consciousness, soaring 

budgets, and publicity. The old NACA days of concentration on aeronautics, 

and especially aerodynamics, were gone forever, as was the agency itself. 

The changes had been long in coming, and the post-Sputnik furor 

only accelerated the process. For the past five years, advanced planners at 

the High-speed Flight Station had devoted increasingly greater amounts 

of time to studying the possibility of hypersonic (mach 5 +) aircraft and 

winged spacecraft. Within the station’s Research Division, winged spacecraft problems and conceptions clearly dominated the staff s thinking, 

not unexpected in light of the increasingly heavy commitment to the 

upcoming X- 15. The orientation at the HSFS dovetailed nicely with the 

new emphasis on unmanned and manned spaceflight implicit in the 

charter of the National Aeronautics and Space Administration. 

The change in the station’s research emphasis during the 1950s can 

be seen by comparing the activities of the three branches of the station’s 

Research Division-the Stability and Control Branch, Aero-Structures 

Branch, and Airplane Performance Branch-in the three years between 

1955 and 1958.’ 

Branch Research Emphasis (1 955) 

Stability Inertial coupling 

& Control Roll-rate requirements 

for mach 2 fighters 

Aero-Structures Transonic airload 

Airplane Transonic drag rise 

Performance 

distribution 

101 

Research Emphasis (1 958) 

Hypersonic boost-gliders 

Reaction control studies 

Winged spacecraft 

& satellites 

Structural loads of 

hypersonic boost-gliders 

Boost-gliders 

c 
ON THE FRONTIER 

The change is even more evident in records of how the professional 

research staff spent its time in 1955, 1957, and 1959.2 

Research Area 1955 1957 1959 

Satellite studies 

Ballistic missile research 

Boost-glide aircraft 

Anti-ICBM studies 

Surface-to-air missiles 

Advanced fighter aircraft 

Supersonic bombers & transports 

Subsonic bombers & transports 

Special projects (VTOLs, etc.) 

5% 

1 

15 

1 

3 

33 

23 

18 

1 

11% 

1 

18 

1 

4 

32 

19 

12 

1 

16% 

3 

35 

2 

4 

16 

18 

3 

3 

Figures may not add to 100% because of rounding. 

This indication of professional interests mirrored trends within the NACANASA as a whole. By the late 1950s, the Ames and Langley laboratories 

were devoting more effort to studying the problems of hypersonic flight 

and reentry from space than they were on aeronautics per se. By 1965, 

over 80% of NASA’s research went to space-related re~earch.~ 

THE OLD ORDER CHANGETH 

On 1 October 1958, the day the National Aeronautics and Space 

Administration officially came into being, the High-speed Flight Station 

had a personnel complement of 292. The new agency employed 8000 

civil servants, 3368 of whom were at Langley. In contrast to the tiny 

NASA station at Edwards, the Air Force contingent there numbered over 

8000. But like the rest of the newly created NASA, the High-speed Flight 

Station was on the verge of rapid growth. The station’s increasingly heavy 

emphasis upon the .problems of winged spaceflight was an unusual, but 

certainly understandable, legacy from its pioneering days of trying to 

“break the sound barrier.” Walter Williams identified a dozen problems 

affecting design and piloting of future high-speed hypersonic craft, 

problems that logically grew out of the Round One experience and would 

be encountered on both “Round Two” (the X- 15) and any “Round Three” 

orbital vehicle: 

Design Problems 

Aerodynamic heating and heat transfer 

Aerodynamic interference 

Aerodynamic efficiency 

102 
I e 

THE X-15 ERA 

Structural design 

Crew survival 

Poor landing configuration 

Large accelerations 

Reaction control operation 

Large changes in control effectiveness 

Large changes in stability 

Inertial coupling 

Presentation of piloting information 

Piloting Problems 

These were all problem areas that the Edwards NASA station could be 

expected to work on in the years ahead.4 

Williams and the professional staff at the HSFS had recognized for 

several years that their activities had broadened considerably beyond 

those envisioned for the “Muroc Flight Test Unit” back in the 1940s. The 

station had a major new role to play with the X- 15 which, together with 

the upcoming Project Mercury program, represented essentially a twopronged approach to studying the problems of manned spaceflight. 

Williams had always sought laboratory status for the station, making it 

equal organizationally with the other NACA laboratories. Of course the 

scope of its work and the size of the station were smaller than those of 

Langley or even Ames. Nevertheless, after independence had been 

achieved from Langley in 1954, laboratory status had been the next 

logical step. To Williams, it was important for reasons of morale, making 

the station’s employees feel equal in prestige and value with the laboratories, 

even though it would not actually affect administration. When NASA 

came into existence , the traditional laboratories, Langley, Ames, and 

Lewis, were redesignated as research centers, to reflect their primary role 

in NASA’s coming activities. Williams’s continued pressing for a redesignation of the High-speed Flight Station now paid off, for the 

scope of the X- 15 program and NASA’s heavy priority on it argued for 

a name change. On 27 September 1959 NASA Headquarters redesignated the High-speed Flight Station the NASA Flight Research Center 

(FRC). That name continued into the 1970s, until it was renamed the 

Dryden Flight Research Center in 1976 in honor of Hugh L. Drydene5 

By the time the station became a center, Walter Williams was gone. 

At the behest of Hugh Dryden, in September he had joined Project 

Mercury, America’s first man-in-space venture, as its operations director. 

His appointment was indicative of the agency’s emphasis upon placing 

individuals with flight-test experience in positions of managerial and 

administrative responsibility for America’s growing manned spacecraft 

program. Williams would be missed, and not simply because he had been 

a superlative station director. He had influenced the local community as 

103 
c 

ON THE FRONTIER 

well; he had worked for high-quality elementary and secondary education in the Antelope Valley school systems and had encouraged station 

employees to take an active part in civic affairs. 

In Williams’s place came Paul F. Bikle, a Pennsylvanian with long 

experience in flight-test projects. Bikle had been Williams’s choice for the 

job, for the two men were close in temperament and outlook. After 

graduation from the University of Detroit with a B.A. in aeronautical 

engineering in 1940, Bikle had joined the staff at Wright Field as a civilian 

flight-test engineer. Well known in military flight testing circles, he was 

serving as technical director of the Air Force Flight Test Center when he 

joined NASA. Like Williams, Bikle had little use for unnecessary paperwork; he often remarked that he would stay with NASA as long as the 

paperwork level remained below what he had experienced in the Air 

Force. 

Bikle replaced Williams at the HSFS on 15 September 1959, oversaw 

its transition to the NASA Flight Research Center, and remained for the 

next 12 years. The center was fortunate in having two such excellent 

administrators sequentially presiding over its activities. Bikle was a short, 

stocky individual who loved poker and cigars, one who had a natural 

affinity for flying and flight testing. A sailplane pilot of unusual ability, in 

February 196 1 he set a world’s altitude record for sailplanes by soaring to 

14 103 meters, a record still standing more than two decades later. Bikle 

believed in doing things quietly and with a minimum of fuss and outside 

attention. “Under Paul Bikle,” one FRC engineer recalled, “we were well 

aware that headquarters was 3000 miles away.” He was at home with the 

engineers, the test pilots, the crew chiefs, and the mechanics. Every day 

he would walk through the building and hangars, asking questions, 

expecting answers, and constantly checking. ‘The careless and unprepared could wind up in the “Bikle barrel” very quickly. Like Williams 

before him, Bikle impressed those who came in contact with him with his 

bluntness, drive, and canny engineering sense. “He’d sit in a meeting, 

listen to us, and say ‘Do this,’ ” one FRC veteran remembered. “We’d all 

think ‘Why the hell didn’t I think of that?’ ” Genuinely liked around the 

center, Bikle was known (but not to his face) as “the ole Man,” and his 

retirement party at the Antelope Valley Country Club still triggers warm 

memories in the minds of Dryden staffers. 

Bikle’s immediate challenge involved shifting the center from planning for the X- 15 program to operating it. He needed people and began 

wiping out manpower-consuming projects to get the force necessary to 

run the new program efficiently. As one of his first moves, Bikle asked 

NASA’s Ira Abbott for 80 new positions and added them to the rapidly 

growing X- 15 team. In accordance with NASA’s center management 

policy, he elevated De E. Beeler from chief of research (and de facto 

deputy) to deputy director of FRC, a position Beeler held until his 

104 
THE X-15 ERA 

Paul F. Bikle. 

retirement. FRC’s budget, personnel, and facilities expanded throughout 

the 1960s, as did NASA’s as a whole, and these expanded resources added 

to Bikle’s administrative tasks. The center’s budget went from $3.28 million 

in 1959 to $20.85 million in 1963 and to $32.97 million in 1968. Staff went 

from 292 to a peak of 669 in 1965. Its facilities expanded as well. The 

center had built a special high-speed flight test corridor for the X- 15 (to 

be discussed later) and added a communications building in 1963, a runway noise measurement system in 1964, and a high-temperature loads 

calibration laboratory in 1966, which proved very useful during the 

YF- 12 Blackbird program.6 

The center’s organization remained largely unchanged from that of 

the 1950s. There were four main divisions, later designated as directorates: 

administration, research, data systems, and flight operation. In November 1965, Bikle added a Biomedical Program Office of equal stature with 

the divisions,* and in 1969 he added a safety director. Bikle also added a 

Projects and Program Management Office that evolved, after he left 

FRC, into a directorate of its own. The four main directorates-research, 

data systems, flight operations, and administration-continued to predominate under center director Lee Scherer until 1976, when, his 

*After Bikle’s departure, biomedical dropped from directorate level, becoming a branch of the 

center director’s office. See app. A for FRC organization during the Bikle and post-Bikle era. 

105 
ON THE FRONTIER 

successor David Scott added a Directorate for Shuttle Operations and 

shifted the projects office into the Directorate for Aeronautical Projects. 

In 1978, center director Isaac Gillam combined projects and research into 

a combined Directorate for Aeronautics. 

Prior to 1963, the various NASA centers reported to the NASA 

associate administrator and had a great deal of leeway in choosing 

projects within the areas of their expertise. In 1963, NASA authorized 

the Office of Advanced Research and Technology (OART) to supervise 

the five original laboratories and stations of the old NACA-Langley, 

Ames, Lewis, Flight, and Wallops Island-and to act as their managerial 

liaison with NASA Headquarters. FRC thus now reported to the NASA 

associate administrator in charge of OART. During the 1960s, OART 

itself was locked into competition for resources and support with the 

Office of Manned Space Flight (OMSF) and the Office of Space Science 

and Applications (OSSA), often causing OART’s engineers to mutter 

among colleagues that senior management had to remember NASA’s 

“first A stood for Aeronautics.” OART itself was expected to act within 

the agency much as the old NACA had acted for the military services and 

industry. OART “would have to anticipate problems, do preliminary 

studies, and carry its investigations to the point where the research could 

be usefully applied-in this case by NASA itself.”’ On this model, FRC’s 

relationship with OART was much like the earlier NACA-HSFS relationship, 

so that major upheavals in NASA itself only rocked FRC when they 

affected OART. OART was always heavily oriented toward winged 

vehicles; in 1972 NASA changed the name to the Office of Aeronautics 

and Space Technology (OAST) “to give adequate recognition to NASA’s 

responsibilities in aeronautics.”’ 

Above all, the decade of the 1960s was the decade of “Round TWO” 

(the X- 15) and, to a certain extent, “Round Three” (the Dyna-Soar and 

its follow-ons) as well. When Bikle assumed leadership of the NASA 

station, Round One was at an end. All eyes and NASA’s attention shifted 

to the rakish black rocketplane called X- 15, which would take the 

center’s research pilots to the fringes of space. 

THE BEGINNING OF ROUND Two 

The X-15’s origins were complex, for its development was stimulated by both foreign and domestic research. A major initial influence 

was the prewar and wartime work of German scientists Eugen Sanger 

and Irene Bredt (later Irene Sanger-Bredt), who in 1944 had set forth a 

concept of a hypersonic rocket-powered aircraft that could be boosted 

into orbit and then glide back to Earth (hence the term boost-glider). 

NACA’s John Becker later wrote: 

106 
Professor Sanger’s pioneering studies of long-range rocket-propelled aircraft had a strong influence on the thinking which led to initiation on the 

X-15 program. Until the Sanger and Bredt paper became available to us 

after the war we had thought of hypersonic flight only as a domain for 

missiles . . . . From this stimulus there appeared shortly in the United States a 

number of studies of rocket aircraft investigating various extensions and 

modifications of the Sanger and Bredt concept. These studies provided the 

background from which the X- 15 proposal emerged.g 

The Sanger-Bredt study directly influenced the birth of the X- 15. 

It also generated a climate from which sprang “Round Three,” the 

abortive Dyna-Soar effort. This occurred because Walter Dornberger, 

the wartime director of Germany’s Peenemunde proving grounds, had 

joined the Bell Aircraft Corporation after the World War I1 and used his 

position to propose various types of Sanger-Bredt-inspired boost-gliders 

for military missions, including orbital strike and reconnaissance. The 

Air Force, generally receptive, sponsored a number of studies that 

coalesced in 1957 as the Dyna-Soar program, later designated X-20A, 

the “Round Three” of Hartley SouK’s research aircraft classification 

scheme. All parties recognized the advisability of first acquiring basic 

hypersonic flight data, especially on hypersonic aerodynamics and heating, 

from a special high-speed research airplane-and thus was born the 

X- 15. 

Within NACA, the first call for such a vehicle came from Robert 

Woods of Bell Aircraft, a member of the prestigious NACA Committee 

on Aerodynamics and the man most responsible for getting Bell involved 

with the X-1 program nearly a decade before. In two committee 

meetings in October 1951 and January 1952, Woods urged that NACA 

study requirements for piloted mach 5 + research aircraft. NACA took no 

action on this proposal at the time, but individual engineers at the Ames, 

Langley, and Edwards facilities undertook their own studies of suitable 

configurations. At Edwards, two of Williams’s advanced planners, Hubert “Jake” Drake and L. Robert Carman, began a series of configuration 

studies. Langley engineers proposed salvaging the X-2 for a hypersonic 

test program, using two jettisonable rockets for additional boost and 

adding reaction controls. NACA headquarters moved slowly and 

deliberately. In mid- 1952, the Aerodynamics Committee endorsed a 

proposal for NACA to “devote a modest effort” to hypersonic studies, 

but Dryden, recognizing that a “modest effort” would stand little chance 

of accomplishing much and that NACA was already overcommitted to 

various projects, reduced it to a study to identify the problems of 

hypersonic flight, rather than research on the problems themselves. In 

August 1953 Drake and Carman submitted a proposal from Edwards to 

Headquarters for a five-phase hypersonic research program leading to 

107 
ON THE FRONTIER 

an orbital winged vehicle. Dryden and Crowley shelved the proposal as 

too futuristic, which indeed it was. Nevertheless, in its bold advocacy of a 

“piggy back” two-stage-to-orbit research craft, the Drake-Carman study 

constituted one of the earliest predecessors of Shuttle. By the end of 

1953, the notion of a hypersonic research aircraft had spawned two 

military study efforts, one by the Air Force Scientific Advisory Board, the 

other by the Office of Naval Research. The next year was the critical year 

of decision for the future X-15.’’ 

At its annual meeting for 1954, the RAPP concluded that NACA 

should procure a new hypersonic research aircraft. Just over a month 

later, on 9 March 1954, NACA headquarters directed the laboratories to 

submit their views to Washington for evaluation. Ames, Langley, and 

Edwards supported the concept. Lewis favored an unmanned rocket that 

could be launched from Wallops. Only Langley and Edwards submitted 

proposed configurations; Langley’s was in the greater detail and hence 

more useful for planning. Langley had created a five-man configuration 

study panel under the direction of John Becker, and this team had 

produced a configuration that closely resembled the later X- 15. When 

soliciting bids for what became the X- 15, NACA sent Becker’s study to 

interested companies. “We didn’t say ‘Here’s what we want,’ ” Becker 

One of the Drake-Carman proposals for advanced hypersonic research aircraft that injluenced later work on the X- 15 and Dyna-Soar. 

108 
THE X-15 ERA 

later recalled, “but we said, ‘Here’s one configuration that we think might 

solve the problems and be what we’re looking for.’ . . . the proposals that 

we got back looked pretty much like the one we had put in.”” 

A Dryden-arranged briefing of the military services on the Becker 

study in July 1954 met with enthusiastic endorsement. By October 1954, 

the Air Force and NACA had realized that such a program would be so 

large and expensive that a joint agency approach was desirable. On 18 

October the NACA, Air Force, and Navy created a three-man hypersonic 

aircraft committee to derive the precise specifications for the proposed 

airplane; Hartley SoulC represented NACA interests on the panel. 

Walter Williams’s staff at the High-speed Flight Station furnished the 

committee with a detailed study of the instrumentation requirements. On 

23 December 1954 Dryden and representatives from the Air Force and 

Navy signed a Memorandum of Understanding. NACA would have 

technical control of the project, the Air Force and Navy would fund the 

design and construction phases, and the Air Force would administer 

those phases. Upon completion of contractor testing, the aircraft would 

be turned over to NACA (NASA, as it turned out), which would conduct 

the flight testing and report results. The memo concluded that 

“accomplishment of this project is a matter of national urgency.”l2 

The three parties created a Research Airplane Committee, an 

interagency body of senior-level executives-Dryden represented NACA 

on the body-to supervise the project. Program participants recall that 

the committee, popularly known as the X- 15 Committee, did not exert 

much influence or control. It served primarily a psychological and 

political function and was largely honorary. The committee did not 

dabble in the design of the airplane; this was left up to the laboratoriesespecially Langley and the High-speed Flight Station-the contractor, 

and the earlier RAPP headed by Soul& Rather it offered high-level 

sanction of lower-level initiatives. As one senior engineer recalled, it “met 

once in a while, but usually provided only a rubber stamp. And it was 

useful [to get a budget approved] to say ‘And here’s what the X-15 

Committee wants to do.’ ”13 The committee continued in existence until 

26 October 1967, when OART closed it down. Its last significant action 

had been on 18 February 1964, when committee members amroved the 

Langley-developed Hypersonic Ramjet Experiment (HRk) for the 

X- 15A-2. 

The NACA- Air Force- Navy specification panel by mid-December 

1954 had stipulated that the craft should be capable of attaining an 

altitude of 76 000 meters and an airspeed of 2000 meters per second 

(mach 6 +). On 30 December 1954 invitations to bid on the contract were 

sent to 12 prospective contractors. Only 4 eventually submitted competitive 

designs: Bell, Douglas, North American, and Republic. For various 

technical reasons, Bell and Republic were quickly eliminated from 

109 
ON THE FRONTIER 

serious consideration, and the competition became a neck-and-neck race 

between North American Aviation and Douglas. Douglas proposed a 

magnesium structure for the craft, but North American preferred 

Inconel, a nickel alloy, and this coincided with the dominant view at 

Langley. A final NASA- Air Force-Navy listing ranked the proposals in 

order: 

1. North American (81.5 points out of a possible 100) 

2. Douglas (80.1 points) 

3. Bell (75.5 points) 

4. Republic (72.2 points) 

On 30 September 1955 the Air Force informed North American that it 

had won the X-15 competition. The X-15 now had a manufacturer. 

Round Two was under way.14 

NECESSARY PREPARATIONS 

The X- 15 program involved building three research airplanes; 

modifying two B -52 bombers to air-launch them; developing a powerful, 

fully reusable “man-rated” rocket engine for the craft; constructing a 

special aerodynamic test range running from Utah to Edwards, across 

the Nevada and California deserts; devising a special full-pressure flight 

suit; and building a special motion simulator connected to analog 

computing equipment-eventually X-15 pilots spent 8 to 10 hours in 

the simulator practicing each 10-12 minute flight. All these developments proceeded relatively smoothly, with the exception of development 

of the craft’s 250 000-newton (57 000-lb-thrust) rocket engine, the 

Thiokol XLR-99, which encountered various delays and difficulties that 

forced North American to substitute two of the older XLR- 1 1 engines 

first used in the X-1 series, until the larger powerplant was ready for 

flight in late 1960. The X-15 airplane itself was ready in mid-1959. 

One of the most important aspects of the X- 15 effort, and one that 

the High-speed Flight Station was intimately involved with, was creation 

of the X- 15’s tracking range, the so-called “High-Range,” short for High 

Altitude Continuous Tracking Radar Range. The NACA and Air Force 

cooperated in planning the range, with the High-speed Flight Station’s 

instrumentation staff under Gerald Truszynski determining its layout. 

Truszynski’s staff informed the RAPP in November 1955 that the range 

should be at least 640 kilometers long, with three radar tracking stations 

able to furnish precise data on aircraft position, reentry prediction, 

geometric altitude, and ground speed. It required an air-launch site 

located over an emergency dirt landing area, intermediate dirt landing 

sites, intermediate launch (drop) sites, nearby airfields that could be used 

for radar site support, and a “reasonably straight course.” Truszynski 

110 
e u. 

THE X-15 ERA 

A cutaway drawing shows internal details of the North American X- 15 rocket-propelled 

research aircrajl. 

and his staff concluded that the best course lay on a line from Wendover, 

Utah, to Edwards, with tracking stations at Ely and Beatty, Nevada, and 

at Edwards. The range would take the X-15 over some of the most 

beautiful, rugged, and desolate terrain in the Western Hemisphere. It 

would fly high over Death Valley before swooping down over the Searles 

basin to a landing at Rogers Lake. In 1956, construction started on the 

High Range, and it was ready for operation in July 1958. It measured 

780 kilometers long, with a corridor width of 80 kilometers. The Ely, 

Beatty, and Edwards tracking stations had radar and telemetry tracking 

with oscillograph recording, magnetic tape data collection, and console 

monitoring services. Each maintained a “local plot” of the X-15 as it 

passed on its way, much as national Air Route Traffic Control Centers 

process airliners on transcontinental flights. Edwards also had a master 

plot, and in the technical jargon of electronics engineers, the three sites 

had “interstation communication” via radio and telephone; real-time data 

passed to and fro from one to the other as the X- 15 sped along. On 

every flight, 87 channels, sampled 10 times per second, relayed information from the plane to the ground. The range would also prove beneficial 

to later NASA research involving vastly different aircraft. The three 

tracking stations did not come cheap: the Edwards station cost NASA 

$4 244 000; the other two together cost about the same. The Air Force 

spent another $3.3 million on High Range construction.15 

Aside from its involvement in the High Range, the High-speed 

Flight Station in the years prior to the arrival of the X- 15 supported the 

design and development stages of the program with such activities as the 

111 
* 

ON THE FRONTIER 

reaction control studies on the X-1B and later YF-104AY and the 

sidestick evaluation on the F- 107. Station representatives reviewed 

development progress on the aircraft, attended meetings with the 

contractor, participated in mock-up inspection, and generally supported 

NACA’s-and later NASA’s-involvement in the program with informed 

criticism and suggestions. When the first X-15 arrived at the HighSpeed Flight Station in the early months of 1959, the station’s technical 

staff was more than ready to begin work on it. 

The first of the three X-15s arrived at the High-speed Flight 

Station in mid-October 1958, trucked over the hills from the plant in Los 

Angeles. It was joined by the second airplane the following April. In 

contrast to the relative secrecy that had attended flight tests with the X- 1 

a decade before, the X- 15 was pure theater. 

The program inspired a great deal of public attention, coming, as it 

did, after Sputnik and during the race between the U.S. and U.S.S.R. to 

orbit a man, a race won by the Soviet Union. North American erected a 

huge neon sign over its plant reading “Home of the X- 15.” Journalists 

flocked to Edwards for the first contractor test flights; international 

rivalry with the Soviet Union received less attention from the press than 

did the idea of the X- 15’s being a tool in America’s “War against Space,” as 

one journalist tagged it. Implicit with this were literary “How do they do 

it?’’ looks at the test pilots, writers waxing eloquent over the airmen going 

out and confronting the X- 15 mano a mano. The project even gave rise to 

a ghastly Hollywood film, incorporating all the hackneyed stereotypes of 

celluloid test flying. And then, as Project Mercury moved from drawing 

board to launch pad, the camera crews and journalists left Edwards for 

Cape Canaveral; stayed there through Gemini, Apollo, and Skylab; and 

ventured back to the hinterlands of the high desert only when the squat 

Shuttle arrived on the scene. 

The X-15’s contractor program lasted two years, from mid-1959 

through mid-1960. North American had to demonstrate the craft’s 

general airworthiness during flights above mach 2 , and successful 

operation of its new XLR-99 engine before delivering the craft to 

NASA. Anything beyond mach 3 was considered a part of the government’s 

research obligation. The task of flying the X-15 during the contractor 

program rested in the capable hands of Scott Crossfield, who had left 

NACA to join North American and help shepherd the craft through its 

long development. Crossfield completed the first captive flight on 10 

March 1959 and first glide flight on 8June. Just prior to landing, the 

plane began a series of increasingly wild pitching motions; thanks to 

Crossfield’s instinctive corrective action, the plane landed safely. North 

American’s engineers subsequently modified its boosted control system 

to increase the control rate response. The X- 15 never again experienced 

the porpoising motions that had threatened it on its first flight. On 17 

112 
THE X-15 ERA 

The X-15 launches from its B-52 mothership on one of the early contractor demonstration Jzights. 

The X-15 begins its climb after launch. 

113 
r * P 

ON THE FRONTIER 

Followed b~ a Lockheed F-104A Staqighter chase plane, thefirst North American X- 15 

sinks toward touchdown on Rogers Dry Lake following a research flight. Official USAF 

photo. 

September the X- 15 completed its first owered flight, when Crossfield 

A series of ground and in-flight accidents marred the X-15’s 

contractor program, fortunately without injuries or even greatly delaying 

the program. On 5 November 1959 a small engine fire-always extremely hazardous in a volatile rocket airplane-forced Crossfield to 

make an emergency landing on Rosamond Dry Lake; the X- 15 landed 

with a heavy load of propellants and broke its back, grounding this 

particular X- 15 for three months. During a ground engine test with the 

third X-15 (the first one equipped with the large Thiokol engine), a 

stuck pressure regulator caused the craft to explode, necessitating virtual 

rebuilding. The second X- 15 was actually the first of the series to test-fly 

the large XLR-99 engine, and after adding the engine to the other two 

craft, North American delivered the last of the X- 15s to NASA in June 

1961. By that time, NASA, Air Force, and Navy test pilots had been 

operating the X-15 on government research flights for just over a 

year. l7 

flew the second airplane to mach 2.1 1. l? 

RESEARCHING THE FRINGES OF SPACE 

The government phase of the X- 15’s research program involved 

four broad objectives: verification of predicted hypersonic aerodynamic 

behavior and hypersonic heating rates, study of the X- 15’s structural 

114 
THE X-15 ERA 

characteristics in an environment of high heating and high flight loads, 

investigation of hypersonic stability and control problems during atmospheric exit and reentry, and investigation of piloting tasks and pilot 

performance. By late 1961, these four areas had been generally examined, 

though detailed research continued to about 1964 on the first and third 

aircraft, and to 1967 with the second (the X- 15A-2). Before the end of 

1961, the X- 15 had attained its mach 6 design goal and had flown well 

above 60 000 meters; by the end of the next year the X- 15 was routinely 

flying above 90 000 meters. Within a single year, the X- 15 had extended 

the range of winged aircraft flight speeds from mach 3.2 to mach 6.04, 

the latter achieved by Air Force test pilot Bob White on 9 November 

1961. 

The intensive flight program on the X-15 revealed a number of 

interesting things. Physiological researchers discovered that the heart 

rates of X-15 pilots varied between 145 and 180 beats per minute on a 

flight, as compared to a normal of 70 to 80 beats per minute for test 

missions in other aircraft. Aeromedical researchers eventually concluded 

that prelaunch anticipatory stress, rather than actual postlaunch physical 

stress, influenced the heart rate. They believed, correctly, that these rates 

could be considered as probable baselines for predicting the physiological 

behavior of future pilot-astronauts. Aerodynamic researchers found 

remarkable agreement between the tunnel tests of exceedingly small 

X- 15 models and actual results, with the exception of drag measurements. 

Drag produced by the blunt aft end of the aircraft proved 15% higher on 

the actual aircraft than wind-tunnel tests had predicted.* At mach 6, the 

X-15 absorbed eight times the heating load it experienced at mach 3, 

with the highest heating rates occurring in the frontal and lower surfaces 

of the aircraft, which received the brunt of airflow impact. During the 

first mach 5 + excursion, four expansion slots in the leading edge of the 

wing generated turbulent vortices that increased heating rates to the 

point that the external skin behind the joints buckled. As a solution, 

NASA technicians added small Inconel alloy strips over the slots, and the 

X-15 flew without further evidence of buckling. It was “a classical 

example of the interaction among aerodynamic flow, thermodynamic 

properties of air, and elastic characteristics of structure.”’* 

Heating and turbulent flow generated by the protruding cockpit 

posed other serious problems; on two occasions, the outer panels of the 

X- 15’s heavy glass cockpit windshields fractured because heating loads 

in the frame overstressed the soda-lime glass. NASA solved the difficulty 

*Correlating full-scale flight-test measurements of base drag with predicted drag values from 

tunnel tests continues to pose serious challenges for engineers, as evidenced by continuing NASA 

research on this subject. Many aircraft continue to exhibit much higher base drag in actual flight 

than has been indicated by tunnels. 

115 
ON THE FRONTIER 

by changing the cockpit frame from Inconel to titanium, modifying its 

configuration, and replacing the outer glass panels with high-temperature 

alumina-silica glass. Another problem concerned an old aerodynamics 

and structures bugaboo, panel flutter. Panels along the flanks of the 

X-15 fluttered at airspeeds above mach 2.4, forcing engineers to add 

longitudinal metal stiffners to the panels. All this warned aerospace 

designers to proceed cautiously. John Becker, writing in 1968, noted of 

the X- 15 experience, 

The really important lesson here is that what are minor and unimportant 

features of a subsonic or supersonic aircraft must be dealt with as prime design 

problems in a hypersonic airplane. This lesson was applied effectively in the 

precise design of a host of important details on the manned space vehicle^.'^ 

A serious roll instability predicted for the airplane under certain 

reentry conditions posed a serious challenge to flight researchers. To 

simulate accurately the reentry profile of a returning winged spacecraft, 

the X- 15 had to fly at angles of attack of at least 17”. Yet the cruciform 

“wedge” tail, so necessary for stability and control in other portions of the 

plane’s flight regime, actually prevented it from being flown safely at 

angles of attack greater than 20” because of potential rolling problems. 

By this time, FRC researchers had gained enough experience with the 

XLR-99 engine to realize that fears of thrust misalignment-a major 

reason for the large vertical fin-were unwarranted. The obvious solution was simply to remove the lower half of the ventral fin, a portion of 

the fin that X- 15 pilots had to jettison prior to landing anyway so that 

the craft could touch down on its landing skids. Removing the ventral 

produced an acceptable tradeoff. While it reduced stability by about 50% 

at high angles of attack, it greatly improved the pilot’s ability to control 

the airplane. With the ventral off, the X-15 could now fly into the 

previously “uncontrollable” region above 20” angle of attack with 

complete safety. Eventually the X- 15 went on to reentry trajectories of 

up to 26”, often with flight path angles of - 38” at speeds up to mach 6, 

a much more demanding piloting task than the shallow entries flown by 

manned vehicles returning from orbital or lunar missions. Its reentry 

characteristics were remarkably similar to those of the later NASA Space 

Shuttle orbiter.** 

When Project Mercury took to the air, it rapidly eclipsed the X- 15 

in glamour. FRC’s researchers and NASA Headquarters viewed the two 

programs as complementary, however. Mercury dominated some of the 

research areas that had first interested X- 15 planners, such as “zero g” 

weightlessness studies. The use of reaction controls to maintain a 

vehicle’s attitude in space proved academic after Mercury flew, but the 

X- 15 had already proved them and would also furnish valuable design 

116 
THE X-15 ERA 

information on the use of blending reaction controls with conventional 

aerodynamic controls during an exit and reentry, a matter of concern to 

subsequent Shuttle development. The X- 15 experience clearly demonstrated the ability of pilots to fly rocket-propelled aircraft out of the 

atmosphere and back in to precision landings. Flight Research Center 

director Bikle saw the X- 15 and Mercury as a 

parallel, two-pronged approach to solving some of the problems of manned 

space flight. While Mercury was demonstrating man’s capability to function 

effectively in space, the X- 15 was demonstrating man’s ability to control a 

high-performance vehicle in a near-space environment. . . . considerable new 

knowledge was obtained on the techniques and problems associated with lifting 

reentry. 21 

Operationally, the X-15 gave the Flight Research Center staff a 

number of headaches. Because of the complexity of its systems, the plane 

experienced a number of operational glitches that delayed flights, 

aborted them before launch, or forced abandonment of a mission after 

launch. Early in the program, the X- 15’s stability augmentation and 

inertial guidance systems were two major problem areas. NASA eventually replaced the Sperry inertial unit with a Honeywell unit first designed 

for the Dyna-Soar. The plane’s propellant system had its own weaknesses. 

Pneumatic vent and relief valves and pressure regulators gave the 

greatest difficulties, followed by spring pressure switches in the auxiliary 

power units, the turbopump, and the gas generation system. NASA’s 

mechanics routinely had to reject 24 to 30% of spare parts as unusable, a 

clear indication of the difficulties of devising industrial manufacturing 

and acceptance test procedures when building for use in an environment 

at the frontier of science.22 Weather posed a critical factor. Many times 

Edwards enjoyed fine weather, the lakebed bone-dry, while upcountry 

the High Range was covered with clouds, alternate landing sites were 

flooded, or some other meterological condition postponed a mission. In 

one case, weather and minor maintenance kept one X- 15 grounded 

from mid-October 1961 to early January 1962. When it finally flew, the 

pilot had to make an emergency landing up range. Weather and 

maintenance then grounded the plane until mid-A~ril.~~ 

The X- 15 had its share of accidents, one of which killed an Air 

Force test pilot; another seriously injured a NASA research pilot. As 

previously mentioned, Scott Crossfield once made an emergency landing 

on Rosamond Lake with an X- 15 damaged by an engine fire; the plane 

broke its back on landing, necessitating lengthy repairs. The third X- 15 

blew up during ground testing of its XLR-99 engine, but it too was 

rebuilt. In November 1962, an engine failure forced Jack McKay, a 

NASA veteran of Round One, to make an emergency landing at Mud 

117 
ON THE FRONTIER 

Lake, Nevada, in the second X-15; its landing gear collapsed and the 

X- 15 flipped over on its back. McKay was promptly rescued by an Air 

Force medical team standing by near the launch site, and eventually 

recovered to fly the X-15 again. But his injuries, more serious than at 

first thought, eventually forced his retirement from NASA. In November 

1967, Mike Adams was killed in a strange accident in the third X- 15 that 

will be discussed later in great detail. One of the most remarkable 

close calls in the X- 15 program involved Air Force test pilot William J. 

“Pete” Knight. In June 1967 he experienced a complete electrical 

failure while climbing through 30 000 meters at mach 4+. With no 

computed information and guidance, Knight continued to climb, suddenly reduced to “seat of the pants” flying technique. During reentry he 

managed to restart one of the auxiliary power units, restoring some 

instruments, and made an emergency landing at Mud Lake, for which he 

received the Distinguished Flying Cross. 

THE X- 15 FOLLOW-ON PROGRAM, 1963- 1967 

Within NACA and later NASA, developing the X- 15 had been left 

largely in the hands of Langley, the center most closely involved in 

determining its mission and configuration, with important inputs from 

the other centers, especially the High-speed Flight Station. The flight 

research program was the province of the Flight Research Center with 

liaison and support from the Air Force Flight Test Center at Edwards. In 

the summer of 1961, as the X-15 approached its maximum performance during test flights, a new initiative began, one that sprang jointly 

from the Air Force’s Aeronautical Systems Division at Wright-Patterson 

AFB and from NASA Headquarters: using the X-15 as a “testbed” or 

carrier aircraft for a wide range of scientific experiments unforeseen in 

its original conception. 

Pressures had existed even before the X- 15 first flew to extend the 

scope of the program beyond aerodynamics and structural research. 

Researchers at the Flight Research Center had proposed using the 

airplane to carry to high altitude some experiments related to the 

proposed Orbiting Astronomical Observatory; others suggested modifying one of the planes to carry a mach 5 + ramjet for advanced air-breathing 

propulsion studies. Over 40 experiments were suggested by the scientific 

community as suitable candidates for the X- 15 to carry. In August 1961, 

after consulting with Bikle at FRC, NASA Headquarters, and the Air 

Force Aeronautical Systems Division, NASA and the Air Force formed 

an X- 15 Joint Program Coordinating Committee to prepare a plan for a 

follow-on experiments program. Most of the suggested experiments were 

in space science, such as ultraviolet stellar photography. Others supported the Apollo program and hypersonic ramjet studies. A series of 

118 
c e 

THE X-15 ERA 

meetings held at NASA Headquarters over the fall of 1961 between the 

joint committee, Hartley SoulC, and John Stack, then NASA’s director of 

aeronautical research, culminated in approval of the proposed follow-on 

research program and the classification of two groups of experiments. 

Category A experiments consisted of well-advanced and funded experiments having great importance; category B included worthwhile projects 

of less urgency or imp~rtance.~~ 

In March 1962 the X- 15 committee approved the “X- 15 Follow-on 

Program,’’ which NASA announced 13 April in a Headquarters news 

conference presided over by Stack and FRC planner Hubert Drake. 

Drake announced that the first task would be to fly an ultraviolet stellar 

photography experiment from the University of Wisconsin’s Washburn 

Observatory. NASA had investigated the possibility of the X- 15 carrying 

a Scout booster that could fire small satellites into orbit, the entire 

B -52/X- 15/Scout becoming in effect a multistage satellite booster, but 

that the agency finally rejected the idea for reasons of safety, utility, and 

economy. The X- 15’s space science program eventually included 28 

experiments running from astronomy to micrometeorite collection, 

using wingtip pods that opened at 45 000 meters, and high-altitude 

mapping. Two of the follow-on programs, a horizon definition experiment from the Massachusetts Institute of Technology and tests of 

proposed insulation for the Saturn laiinch vehicle, directly affected 

navigation equipment and the thermal protection used on ApolloSaturn. FRC quickly implemented the follow-on program. In 1964, fully 

65% of all data returned from the three X- 15 aircraft involved follow-on 

projects; this percentage increased yearly through conclusion of the 

program.25 

NASA’s major X- 15 follow-on project involved a Langley-developed 

Hypersonic Ramjet Experiment (HRE). FRC advanced planners had 

long wanted to extend the X- 15’s speed capabilities, perhaps even to 

mach 8, by adding extra fuel in jettisonable drop tanks and some sort of 

thermal protection system. Langley researchers had developed a design 

configuration for a proposed hypersonic ramjet engine. The two groups 

now came together to advocate modifying one of the X- 15’s as a mach 8 

research craft that could be tested with a ramjet fueled by liquid 

hydrogen. The proposal became more attractive when the landing 

accident to the second X- 15 in November 1962 forced the rebuilding of 

the aircraft. The opportunity to make the modifications was too good to 

pass up. In March 1963 the Air Force and NASA authorized North 

American to rebuild the airplane with a longer fuselage. Changes were to 

be made in the propellant system; two huge drop tanks (1 X 7 meters) 

and a small tank for liquid hydrogen within the plane were to be added. 

Forty weeks and $9 million later, North American delivered the modified 

plane, designated the X- 15A-2, to NASA in February 1964.26 

119 
a 

ON THE FRONTIER 

The X- 15A-2 first flew in June 1964, piloted by Air Force test pilot 

Bob Rushworth. Early proving flights demonstrated that the plane 

retained satisfactory flying qualities at mach 5 + speeds, though on one 

flight thermal stresses caused the nose landing gear to extend at mach 

4.3, generating “an awful bang and a yaw,” but Rushworth landed safely 

despite blow-out of the heat-weakened tires upon touchdown. In November 1966, Air Force pilot Pete Knight set an unofficial world’s airspeed 

record of mach 6.33 in the plane. NASA then grounded it for application 

of an ablative coating to enable it to exceed mach 7.*’ 

Flight Research Center’s technical staff had evaluated several possible coatings that could be applied over the X- 15’s Inconel structure to 

enable it to withstand the added thermal loads experienced above mach 

6. NASA hoped that such coatings might point the way toward materials 

that could be readily and cheaply applied to reusable spacecraft, minimizing refurbishment costs and turn-around time between flights. Such a 

coating would have to be relatively light; have good insulating properties; 

be easy to apply, cure, and then remove; and be easy to reapply before 

another flight. On FRC’s advice, a joint NASA-Air Force committee 

selected an ablator developed by the Martin Company, MA-25S7 in 

connection with some corporate studies on reusable spacecraft concepts. 

Consisting of a resin base, a catalyst, and a glass bead powder, it would 

protect the X- 15’s structure from the expected 1100°C heating as the 

craft sped through the upper atmosphere. Martin estimated that the 

coating, ranging from 1.5 centimeters thick on the canopy, wings, vertical, 

and horizontal tail down to 0.38 millimeters on the trailing edges of the 

wings and tail, would keep the skin temperature down to a comfortable 

3 15°C. The first unpleasant surprise came, however, with the application of the coating to the X-15A-2: it took six weeks. Because the 

ablator would char and emit a residue in flight, North American had 

installed an “eyelid” over the left cockpit window. It would remain closed 

until just before approach and landing. During launch and climbout, the 

pilot would use the right window, but residue from the ablator would 

render it opaque above mach 6.28 

Late in the summer of 1967, the X- 15A-2 was ready for flight with 

the ablative coating. It had already flown with a dummy ramjet affixed to 

its stub ventral fin; the ramjet, while providing a pronounced nose-down 

trim change, actually added to the plane’s directional stability. The 

weight of the ablative coating-57 kilograms higher than plannedtogether with expected increased drag reduced the theoretical maximum 

performance of the airplane to mach 7.4, still a significant advance over 

the mach 6.3 previously attained with the plane. The appearance of the 

X- 15A-2 was striking, an overall flat off-white finish, the huge external 

tanks a mix of silver and orange-red with broad striping. NASA hoped 

that early mach 7 + trials would lead to tests with an actual “hot” ramjet 

120 
a a c 

THE X-15 ERA 

rather than the dummy now attached to the plane. On 21 August 1967 

Knight completed the first flight in the ablative-coated plane, reaching 

mach 4.94 and familiarizing himself with its handling qualities. His next 

flight, on 3 October 1967, was destined to be the X- 15’s fastest flight and 

the most surprising as well.*’ 

That day, high over Nevada, Knight dropped away from the B-52, 

the heavy X- 15A-2 brimming with fuel. Knight climbed under the full 

thrust of the rocket engine. When the external tanks were emptied, he 

jettisoned them and continued on the craft’s internal supply, leveling off 

at slightly over 30 000 meters. It was a flight in the grand Edwards 

tradition of Yeager and Crossfield. The X- 15A-2’s engine burned 

more than 141 seconds and reached mach 6.72, 7269 kilometers per 

hour-a mark that would stand as a record for winged vehicles until the 

return of the Space Shuttle Columbia from orbit in 1981. Unknown to 

Knight, however, all was not well with the plane. Preflight studies did not 

adequately predict the complex local heating conditions the aircraft 

would experience. Temperatures later determined to have been above 

1650°C (3000°F) burned the ramjet off its pylon and seared a hole 

measuring 18 by 8 centimeters into the ventral fin’s leading edge. An 

airscoop effect channeled hot air into the lower fuselage and damaged 

the propellant jettison system-Knight eventually had to land the plane 

680 kilograms heavier than planned because he could not jettison 

residual fuel. If the heat had damaged the craft’s hydraulics, Knight 

Pete Knight pilots the X-15A-2 on its mach 6.7flight. 

121 
ON THE FRONTIER 

might have had to abandon the plane. Fortunately, that did not happen. 

Knight landed at Edwards, the plane resembling burnt firewood. It had 

been an eventful flight; now the engineers sat down and took a long look 

at what it all meant.30 

What it really meant was the end of the refurbishable spray-on 

ablator concept. It was the closest any X-15 came to structural failure 

induced by heating. The plane was charred on its leading edges and 

nosecap. The ablator had actually prevented cooling of some hot spots by 

keeping the heat away from the craft’s metal heat-sink structure. On 

earlier flights without the ablator, some of those areas remained relatively cool because of heat transfer through the heavy Inconel structure. 

Some heating effects, such as at the tail and body juncture and where 

shockwaves intersected the structure, had been the subject of theoretical 

studies, but had never before been seen on an actual aircraft in flight. To 

John Becker at Langley, the flight underscored “the need for maximum 

attention to aerothermodynamic detail in design and preflight te~ting.”~’ 

To Jack Kolf, an X- 15 project engineer at the FRC, the X- 15A-2’s 

condition “was a surprise to all of us. If there had been any question that 

the airplane was going to come back in that shape, we never would have 

flown it.”32 The ablator had done its job, but refurbishing for another flight 

near mach 7 would have taken five weeks. Technicians would have had 

great difficulty in ensuring adequate depth of the ablator over the structure. 

Obviously, a much larger orbital vehicle would have had even greater problems. The sprayed-on ablator concept thus died a natural death. The unexpected airflow problems with the ramjet ended any idea of using that 

configuration on the X- 15. After the flight, NASA sent the X- 15A-2 to 

its manufacturer for general maintenance and repair. Though the plane 

returned to Edwards in June 1968, it never flew again. 

THE END OF AN ERA 

The third X- 15 featured specialized flight instrumentation and 

displays that rendered it particularly suitable for high-altitude flight 

research. A key element of its control system was a so-called “adaptive” 

flight control system developed by Honeywell; it automatically compensated for the airplane’s behavior in various flight regimes, combining the 

aerodynamic control surfaces and the reaction controls into a single 

control “package.” This offered much potential for future high-performance 

aircraft such as the Dyna-Soar and supersonic transports. 

By the end of 1963, this X-15 had flown above 80 kilometers, the 

altitude that the Air Force recognized as the minimum boundary of 

spaceflight. FRC pilot Joe Walker set an X-15 record for winged 

spaceflight by reaching 107 900 meters, a record that stood until the 

orbital flight of Columbia nearly a decade later. These flights, and others 

122 
R P u 

THE X- 15 ERA 

later, acquired reentry data considered applicable to the design of future 

“lifting reentry” spacecraft such as the present-day Space Shuttle. By 

mid-1967, the X- 15-3 had completed 64 research flights, 21 at altitudes 

above 60 000 meters. It became the prime testbed for carrying experiments to high altitude, especially micrometeorite collection and solarspectrum analysis experiments. 

As had happened in some other research aircraft programs, a fatal 

accident signaled the end of the X- 15 program. On 15 November 1967 

at 10:30 a.m., the X- 15-3 dropped away from its B-52 mothership at 

13 700 meters near Delamar Dry Lake. At the controls was veteran Air 

Force test pilot Maj. Michael J. Adams. Starting his climb under full 

power, he was soon passing through 27 000 meters. Then an electrical 

disturbance distracted him and slightly degraded the control of the 

aircraft. Having adequate backup controls, Adams continued on. At 

10:33 he reached a peak altitude of 80 000 meters. In the FRC flight 

control room, fellow pilot and mission controller Pete Knight monitored 

the mission with a team of engineers. Something was amiss. As the X- 15 

climbed, Adams started a planned wing-rocking maneuver so an onboard camera could scan the horizon. The wing rocking quickly became 

excessive, by a factor of two or three. When he concluded the wingrocking portion of the climb, the X-15 began a slow, gradual drift in 

heading; 40 seconds later, when the craft reached its maximum altitude, 

it was off heading by 15”. As the plane came over the top, the drift 

briefly halted, with the plane yawed 15” to the right. Then the drift 

began again; within 30 seconds, the plane was descending at right angles 

to the flight path. At 70 000 meters, encountering rapidly increasing 

dynamic pressures, the X- 15 entered a mach 5 spin.33 

In the flight control room there was no way to monitor heading, so 

nobody suspected the true situation that Adams now faced. The controllers did not know that the plane was yawing, eventually turning completely around. In fact, control advised the pilot that he was “a little bit 

high,” but in “real good shape.” Just 15 seconds later, Adams radioed 

that the plane “seems squirrelly.” At 10:34 came a shattering call: “I’m in 

a spin, Pete.” A mission monitor called out that Adams had, indeed, lost 

control of the plane. A NASA test pilot said quietly, “That boy’s in 

trouble.” Plagued by lack of heading information, the control room staff 

saw only large and very slow pitching and rolling motions. One reaction 

was “disbelief; the feeling that possibly he was overstating the case.” But 

Adams again called out, “I’m in a spin.” As best they could, the ground 

controllers sought to get the X- 15 straightened out. They knew they had 

only seconds left. There was no recommended spin recovery technique 

for the plane, and engineers knew nothing about the X- 15’s supersonic 

spin tendencies. The chase pilots, realizing that the X-15 would never 

make Rogers Lake, went into afterburner and raced for the emergency 

123 
ON THE FRONTIER 

lakes, for Ballarat, for Cuddeback. Adams held the X-15’s controls 

against the spin, using both the aerodynamic control surfaces and the 

reaction controls. Through some combination of pilot technique and 

basic aerodynamic stability, the plane recovered from the spin at 36 000 

meters and went into a mach 4.7 dive, inverted, at a dive angle between 

40 and 45°.34 

Adams was in a relatively high altitude dive and had a good chance 

of rolling upright, pulling out, and setting up a landing. But now came a 

technical problem that spelled the end. The Honeywell adaptive flight 

control system began a limit-cycle oscillation just as the plane came out of 

the spin, preventing the system’s gain changer from reducing pitch as 

dynamic pressure increased. The X- 15 began a rapid pitching motion of 

increasing severity. All the while, the plane shot downward at 49 000 

meters per minute, dynamic pressure increasing intolerably. High over 

the desert, it passed abeam of Cuddeback Lake, over the Searles Valley, 

over the Pinnacles, arrowing on toward Johannesburg. As the X-15 

neared 20000 meters it was speeding downward at mach 3.93 and 

experiencing over 15 g vertically, both positive and negative, and 8 g 

laterally. It broke up into many pieces amid loud sonic rumblings, 

striking northeast of Johannesburg. Two hunters heard the noise and 

saw the forward fuselage, the largest section, tumbling over a hill. On the 

ground, NASA control lost all telemetry at the moment of breakup, but 

still called to Adams. A chase pilot spotted dust on Cuddeback, but it was 

not the X-15. Then an Air Force pilot, who had been up on a delayed 

chase mission and had tagged along on the X- 15 flight to see if he could 

fill in for an errant chase plane, spotted the main wreckage northwest of 

Cuddeback. Mike Adams was dead, the X- 15 destroyed. NASA and the 

Air Force convened an accident board.35 

Chaired by NASA’s Donald R. Bellman, the board took two months 

to prepare and write its report. Ground parties scoured the countryside 

looking for wreckage, any bits that might furnish clues. Critical to the 

investigation was the cockpit camera and its film. The weekend after the 

accident, a voluntary and unofficial FRC search party found the camera; 

disappointingly, the film cartridge was nowhere in sight. Engineers 

theorized that the film cassette, being lighter than the camera, might be 

further away, to the north, blown there by winds at altitude. FRC 

engineer Victor Horton organized a search and on 29 November, during 

the first pass over the area, W. E. Dives found the cassette, in good 

condition. Investigators meanwhile concentrated on analyzing all telemetered data, interviewing participants and witnesses, and studying the 

aircraft systems. Most puzzling was Adams’ complete lack of awareness of 

major heading deviations in spite of accurately functioning cockpit 

instrumentation. The accident board concluded that he had allowed the 

aircraft to deviate as the result of a combination of distraction, misinter124 
THE X-15 ERA 

preting his instrumentation display-and possible vertigo.* The electrical 

disturbance early in the flight degraded the overall effectiveness of the 

aircraft’s control system and further added to pilot workload. The 

X-15’s adaptive control system then broke up the airplane on reentry. 

The board made two major recommendations: install a telemetered 

headin indicator in the control room, visible to the flight controller, and 

medica P ly screen X- 15 pilot candidates for labyrinth (vertigo) sensitivity. 

As a result of the X-15 crash, FRC added a ground-based “8 ball” 

attitude indicator, displayed on a TV monitor in the control room, which 

furnished mission controllers with “real time” pitch, roll, heading, angle 

of attack, and sideslip information available to the pilot, using this for the 

remainder of the X- 15 program.36 

So passed the third X- 15. The program itself did not long survive. 

NASA had grounded the X- 15A-2 for major repairs by North American Rockwell, a grounding that became permanent. Only the first X- 15 

remained and it soldiered on. Opinion within NASA had long been split 

as to whether the X-15 program should continue. The ramjet and 

proposed X- 15 delta conversion offered hope to zealots that the progam 

might last until 19’72 or 19’73, but the loss of two of the three aircraft 

ended that. As early as March 1964, after consultation with NASA, Brig. 

Gen. James T. Stewart, director of science and technology for the Air 

Force, had determined that the program would end in December 1968.37 

The X-15-1 had just about exhausted its research ability, and it cost 

roughly $600 000 per flight. Even FRC director Paul Bikle believed that 

the program had continued beyond its point of useful return. “X-15” 

and “FRC” had become such synonymous terms that uninformed speculation held that when the X-15 stopped flying, FRC would cease to exist. 

In fact, many other FRC programs could benefit from the resources 

needed to fly the X-15-programs such as the lifting bodies and the 

YF- 12A advanced supersonic mach 3 airplanes. NASA’s OART recognized 

this, so support for continued X-15 operations was not strong. NASA 

did not request funding for operations after December 1968.38 

During 1968, Bill Dana of NASA and Pete Knight of the Air Force 

took turns flying the first X- 15. A variety of weather, maintenance, and 

operational problems caused rescheduling and cancellation of a number 

of flights. On 24 October 1968 Bill Dana completed the first X- 15’s 81st 

flight, the 199th flight of the series. The plane attained mach 5.38 at 

7’7 700 meters carrying a variety of follow-on experiments. Two months 

remained before funding would end, and FRC engineers hoped to get 

the 200th flight before the program closed down. In spite of every effort 

*During testing for the Manned Orbiting Laboratory (MOL) program, Adams had shown an 

unusual susceptibility to vertigo and had experienced vertigo throughout boost to reentry on earlier 

X- 15 flights. Other X- 15 pilots often experienced vertiginous tendencies during boost. 

125 
5 

ON THE FRONTIER 

to ensure that this would become a reality, maintenance and weather 

problems intervened. After several abortive attempts and repeated 

changes in the flight plan, FRC had the X- 15 and B-52 ready for flight 

on 20 December-and Edwards had snow. The support helicopters 

didn’t have the visibility to get airborne and go up range. Technicians 

demated the pair for the last time, then left with the rest of the center’s 

personnel for a wake at Juanita’s saloon in Rosamond. Betty Love, 

assembling the log of the X- 15 trio for the FRC Pilots’ Office, closed the 

entries with a final notation: “This ends an era in flight research history.” 

And indeed it did. 

THE x- 15 IN RETROSPECT 

It was unfortunate that Hugh Latimer Dryden did not witness the 

conclusion of the X-15 program at the center soon to bear his name. 

Dryden had seen so much aviation history, from the early days of 

transonic research in the 1920s when he studied airflow around moving 

propeller tips, through the heyday of the X- 1, X- 15, and into Apollo. 

His voice had been an important one in design of several major systems 

in the X- 15. “It is fair to state,” Jerome Hunsaker and Robert Seamans 

have written, “that Dryden’s 1920 work on supersonic aerodynamics led 

consistently to operational supersonic airplanes, the famous rocketpropelled X- 15, and successful manned space flight.”3g But he was dead. 

Exploratory surgery in 196 1 revealed a serious malignancy. Dryden 

continued working almost to the end, living to see the X-15 hailed as 

the most successful research airplane of all time. His death on 2 December 

1965, at the age of 67, was a great loss to the nation and to NASA. He left 

a rich legacy and an outstanding reputation. Nothing could have satisfied 

him more than the three X- 15s flying in desert skies. 

Tabulating the X- 15’s statistics is easy. Assessing its significance to 

postwar aerospace research and development is more difficult. In 199 

flights, the X- 15 spent 18 hours above mach 1, 12 hours above mach 2, 

nearly 9 hours above mach 3, nearly 6 hours above mach 4, 1 hour above 

mach 5, and scant minutes above mach 6. It flew to a speed of mach 6.72 

and reached an altitude of 108 kilometers. Twelve pilots flew it. Starting 

as a hypersonic aerodynamics research tool, the X- 15 became much 

more than that. What, then, did it accomplish? 

In October 1968 John Becker enumerated 22 accomplishments from 

the research and development work that produced the X-15, 28 

accomplishments from its actual flight research, and 16 from testbed 

investigations. As of May 1968, the X-15 had generated 766 technical 

reports on research stimulated by its development, flight testing, and test 

results, equivalent to the output of a typical 4000-man federal research 

126 
a 

THE X-15 ERA 

center working for two years. As the X-1 had provided a focus and 

stimulus for supersonic research, the X- 15 furnished a focus and 

stimulus for hypersonic studies. A sampling of its accomplishments 

indicates their scope: 

0 Development of the first large restartable “man-rated throttleable 

0 First application of hypersonic theory and wind-tunnel work to an 

0 Development of the wedge tail as a solution to hypersonic 

First use of reaction controls for attitude control in space. 

e First reusable superalloy structure capable of withstanding the 

0 Development of new techniques for the machining, forming, 

0 Development of improved high-temperature seals and lubricants. 

0 Development of the NACA “Q’ ball “hot nose” flow-direction 

sensor for operation over an extreme range of dynamic pressures 

and a stagnation air temperature of 1900°C. 

0 Development of the first practical full-pressure suit for pilot 

protection in space. 

Development of nitrogen cabin conditioning. 

Development of inertial flight data systems capable of functioning 

0 Discovery that hypersonic boundary layer flow is turbulent and 

0 Discovery that turbulent heating rates are significantly lower than 

0 First direct measurement of hypersonic skin friction, and discov0 Discovery of “hot spots” generated by surface irregularities. 

Discovery of methods to correlate base drag measurements with 

tunnel test results so as to correct wind tunnel data. 

0 Development of practical boost-guidance pilot displays. 

0 Demonstration of a pilot’s ability to control a rocket-boosted 

aerospace vehicle through atmospheric exit. 

0 Development of large supersonic drop tanks. 

Successful transition from aerodynamic controls to reaction controls, 

0 Demonstration of a pilot’s ability to function in a weightless 

0 First demonstration of piloted, lifting atmospheric reentry. 

First application of energy-management techniques. 

rocket engine, the XLR-99. 

actual flight vehicle. 

directional stability problems. 

temperatures and thermal gradients of hypersonic reentry. 

welding, and heat-treating of Inconel X and titanium. 

in a high-dynamic pressure and space environment. 

not laminar. 

had been predicted by theory. 

ery that skin friction is lower than had been predicted. 

and back again. 

environment. 

127 
ON THE FRONTIER 

Studies of hypersonic acoustic measurements used to define 

insulation and structural design requirements for the Mercury 

spacecraft. 

Use of the three X- 15 aircraft as testbeds carrying a wide variety 

of experimental packages4’ 

The X-15 also made its mark in many other ways. When NACA 

began its development, the science of hypersonic aerodynamics was in its 

infancy; the few existing hypersonic tunnels were used largely for studies 

in fluid mechanics. Aerodynamicists feared that there might be a 

hypersonic “facility barrier,” much like the earlier transonic tunnel 

trouble that led to the Bell X- 1 and Douglas D-558, so that hypersonic 

tunnel tests might prove of little value in predicting actual flight 

conditions. The X-15 disproved this; predicted wind tunnel data and 

data flight testing of the airplane generally showed remarkable agreement. Proving that hypersonic laminar flow conditions did not develop 

led to the disappearance of this “technical superstition,” and recognition 

that the small surface irregularities that prevent laminar flow at low 

speed also prevent its formation at hypersonic speeds. Like the earlier 

X- 1, the X- 15 encouraged a great deal of ground research and simulation techniques. So successful were these methods and so great was 

the engineers’ confidence in these methods and the X- 15’s flight results 

that the X-15 wound up actually decreasing the likelihood of NASA’s 

developing any future hypersonic research aircraft with the prime 

justification being the generation of unique and otherwise unobtainable 

data. Any future research aircraft would be built more for “proof of 

concept” purposes than for acquiring information unobtainable by other 

means. At the conclusion of the X- 15 program, the German Society of 

Aeronautics and Astronautics presented the NASA X- 15 team with the 

Eugen Sanger Medal-. fitting and appropriate honor. In his acceptance address on behalf of the team, John Becker stated that “no new 

exploratory research airplane can ever again be successfully promoted 

primarily on the grounds that it will produce unique flight data without 

which a successful technology cannot be achieved.”41 

The X- 15 story had another side: its effect upon the people of the 

team. Their intense and devoted work was recognized in numerous 

honors: the Sanger Medal, the Collier Trophy, the Harmon Trophy, the 

Octave Chanute Award, the NASA Medal for Exceptional Bravery, the 

Thomas D. White Space Trophy, the NASA Exceptional Service Medal, 

the NASA Distinguished Service Medal, the NASA Medal for Outstanding Leadership, the Iven C. Kincheloe Memorial Award, the FA1 Gold 

Air Medal, the Lawrence B. Sperry Award, the Sylvanus Albert Reed 

Award, the Haley Astronautics Award, the Flight Achievement Award, 

the David C. Schilling Trophy, the NASA Group Achievement Award. All 

these, at one time or another, went to the X-15 team or its members. 

128 
P L * 9- ;5 c 

THE X- 15 ERA 

The public had little understanding of the X- 15 and, after the early 

fanfare, saw only the occasional items in newspaper back pages on new 

speed and altitude marks-as if that was all the X- 15 did. Laymen could 

not understand what went into a flight: the mission planning; the hours 

of simulator time; the flight practice; the endless maintenance; the 

annoying delays for weather; the excitement as the B-52 took off; the 

long wait to drop or, disappointingly, to an abort; the moment of launch, 

with ignition and boost, or an abort and emergency landing; the 

tenseness of the control room; the hypersonic glide back; the chase and 

X- 15 coming in like a flock of ducks; the resounding smack as its skids 

thumped into the lake; and, once again, the maintenance, debriefing, 

data analysis, and planning for the next mission. They could not know 

the strong bonds the program forged, nor the collective worry produced 

by an errant flight or an emergency condition, nor the heartache 

generated by the death of Mike Adams. They could not fathom the 

emotional and psychological release of the parties at Juanita’s. For a 

decade, the Flight Research Center sustained this effort, and its personnel found new kinship and dedication. When the X- 15s left the lake for 

the last time, a little bit of the center and its personnel went with them. 

But there were other programs, other vehicles. 

129 

7 

Serving Gemini and Apollo: 1962 - 196’7 

NASA’s major priority in the 1960s was, of course, space. The 

agency’s activities were related to three major manned spacecraft 

projects, Mercury, Gemini, and Apollo. Beyond Apollo, the agency had 

at best vague plans for some sort of semipermanent orbital space station 

supplied by an Earth-to-station “shuttle.” In truth, however, NASA had 

not formulated long-range plans beyond the lunar landing. Because of 

the intensity of the space program, particularly during the early 1960s, 

NASA channeled the activities of all the field centers and stations toward 

some aspect of it. The Flight Research Center during this time concentrated its efforts on various means of returning men from space-means 

such as the Paresev and lifting body, which will be discussed later-and 

analyzing how to land on the moon. This work was directly related to Gemini 

and Apollo, and to the later Space Shuttle as well. However, Flight 

Research Center labored under one serious handicap during the 1960s, a 

handicap that almost cost the center its existence. In an agency dominated by spaceflight, FRC appeared to be anachronistically obsessed with 

aeronautics. 

WHITHER FRC? 

In point of fact, FRC‘s research during the 1960s was oriented 

primarily toward spaceflight, though with a heavy aeronautical flavor: 

hypersonic flight within the upper atmosphere and into and back from 

space; the low-speed handling qualities of spacecraft; lifting reentry 

schemes; and support of space research at other NASA centers, such as 

high-altitude drop tests of Mercury spacecraft’s drogue parachute. Since 

FRC relied heavily upon research aircraft-vehicles having wings-the 

center seemed to be concentrating its activity on the airplane in the era of 

the spacecraft. But these aircraft were actually being used as tools for 

studying problems that were basically space technology. Research on the 

X- 15, for example, clearly benefited spaceflight studies more than, say, 

supersonic aerodynamic research. This tended to be missed among 

131 
I a 

ON THE FRONTIER 

individuals who were not familiar with the true scope of the center’s 

research. FRC suffered simply because no spacecraft were being managed from the center, no boosters were being developed by its engineers, 

no rockets were being launched there. 

As early as 195’7, the percentage of FRC’s research staff involved 

with space studies had begun to grow. This, too, was missed, possibly 

because most of these internal studies went no further than FRC’s “front 

office,” in part because many of them were speculative and not directly 

involved with mainstream NASA budget items. Even in the 1960s, the 

actual percentage of FRC’s personnel involved in space-related research 

appears from available internal evidence to have been higher than shown 

in published NASA statements. Table 3 shows the distribution of 

permanent personnel at FRC by fiscal year and budget activity, as set 

forth in NASA’s budget estimates, at two year intervals from 1960 

through 1968. A closer examination of these data, however, raises serious 

questions as to their accuracy and possibly indicates a source of misinformation that might well have convinced many within NASA and outside 

the agency-including Congress-that FRC was far less in step with the 

times than it actually was. 

The NASA budget estimate for 1960 states that approximately 90% 

of FRC’s staff was engaged in “aircraft technology.” Yet by 1959 the 

personnel breakdown in HSFS internal planning documentation indicates that no more than 40% were working on aircraft studies. Fully 35% 

were studying boost-glide (i.e., orbital) aircraft, another 16% were 

examining satellites (both manned and unmanned), 5% were engaged in 

ICBM and anti-ICBM research, and 4% were studying antiaircraft 

missiles.’ These figures certainly could not have changed in favor of 

aeronautics in one year. Clearly budget request statistics from 1960 to 

1968 are misleading because they lump together such major activities as 

the X- 15 and lifting body programs as “aircraft technology” when, in 

fact, these programs were space related. In 1962, fully 84.5% of FRC’s 

staff was officially listed under “aircraft technology,” but it is doubtful if 

more than 20% was engaged on purely aeronautical (i.e., flight within 

the atmosphere) projects at that time, and no more than 40% in 1968. 

Since so many of the X-15 and lifting body programs were related to 

manned spaceflight, it is inconceivable that FRC, in 1964, had only 8.3% 

of its staff investigating manned spaceflight activities. This figure should 

have been in the author’s calculations, about 40% as well, based on the 

flight research activities surrounding these projects, the number of 

employees engaged with them, and the amount of paperwork (an indication of administrative “prioritizing” of projects) generated by them. 

These statistics from NASA’s budget requests are misleading in 

another way: they ignore the trait of “ad hocracy” (in Alvin Toffler’s 

132 
E 

I P s 0 

SERVING GEMINI AND APOLLO 

Table 3 

Distribution of FRC Permanent Personnel by Program, 

1960- 1968 

(Number Assigned and Percentage of Total) 

Program 1960” 1962 1964 1966 1968 

Manned Space Flight 0 6 50 34 0 

Space Applications 0 0 0 0 0 

Unmanned Space Investigations 0 1 3 1 0 

0.0% 1.2% 8.3% 5.6% 0.0% 

0.0 0.0 0.0 0.0 0.0 

0.0 0.2 0.5 0.2 0.0 

Space Research & Technology 0 45 51 1 04 92 

0.0 8.6 8.4 17.2 16.2 

Aircraft Technology --- 443 344 308 325 

90.0 84.5 56.8 51.1 57.4 

Supporting Activitiesb --- 29 157 156 1 49 

10.0 5.5 26.0 25.9 26.3 

”Actual positions unavailable for FY 1959-60; percentages from NASA Office of Programming, 

Budget Operations Div., Histg, of Budget Plans, Actual Obligations, and Actual Expenditures for FY I959 

through 1963 (NASA, 1965), sect. 8. 

bIncludes tracking and data acquisition, data analysis, and technology utilization staff. 

SOURCE: Nimmen, Bruno, and Rosholt, NASA Historical Data Book, 1958-1968, vol. 1, NASA 

Resources, NASA SP-4012 (Washington, D.C.: NASA, 1976), Table 6-31, p. 277. 

words) that has always characterized FRC’s administrative style. Its small 

staff has never been divided by rigid administrative lines and networks 

separating programs, authorities, and administrative units; instead, specialized small work forces have been formed to accomplish certain 

projects or goals-such as the Paresev, lifting body, and lunar landing 

simulator.* Workers ostensibly “assigned’ to aeronautics projects might 

suddenly be called upon to participate in a space-related project. They 

might still show up on organizational charts as “aeronautics” personnel, 

when, in fact, they often flitted back and forth from “aero” to “space” as 

the research need arose. 

Doubtless the failure to portray adequately the wide-ranging air 

and space interests of FRC lay equally between FRC and NASA Headquarters. FRC’s casual though highly effective administration showed 

little inclination to set up a sharply structured bureaucracy that would 

clearly divide the activities of the center between aeronautics and astronautics, or spaceflight. Because of the small size of the center and the 

need to shift people to meet constantly changing project structures, such 

a bureaucracy would have made little sense anyway. Unfortunately, 

133 
. ON THE FRONTIER 

the persons in NASA Headquarters charged with preparing and submitting budget requests to Congress type-cast the FRC as an “aeronautics” 

center. Communication between FRC and Headquarters was inadequate, 

although Paul Bikle recognized the danger of being perceived as an 

aeronautics-only facility and worked hard to move FRC into the mainstream of space-related programs. Paresev, lifting bodies, and the lunar 

lander were Bikle initiatives. FRC’s staff may well have failed to grasp just 

how single-minded the non-NASA governmental community, especially 

Congress, was when it came to “emphasizing” aeronautics or astronautics 

in the early 1960s. 

All this would constitute little more than a curious footnote to FRC’s 

managerial style and visibility during the 1960s were it not for a critical 

event: an attempt by some congressional elements to close down the 

center at the conclusion of the X- 15 program. 

As has been mentioned, the X- 15 so dominated FRC’s activities in 

the early 1960s that some saw FRC and X- 15 as so intertwined that the 

end of the latter would spell the demise of the former. This feeling had 

reached the halls of Congress, and in the summer of 1963, during 

consideration of NASA’s 1964 budget, the influential House Committee 

on Science and Astronautics (later the House Committee on Science and 

Technology) recommended closing the Flight Research Center since, in 

members’ judgment, “no known future aircraft projects will specifically 

require the continued existence of the Flight Research Center beyond the 

date when the X- 15 project will be ~ompleted.”~ Dr. Raymond Bisplinghoff, 

OART director, worked hard over the next few weeks to save FRC, 

pointing out that NASA envisioned its participation in a range of 

programs in both aeronautics and space activities. Fortunately, the 

Senate Committee on Aeronuatical and Space Sciences restored funding 

for the FRC, on grounds that it would be vital to the upcoming American 

supersonic transport testing program. By the end of the summer, FRC 

was safe, having survived a serious attempt to legislate its demi~e.~ 

With hindsight, it is ironic that FRC was saved at a critical juncture of 

its existence by an anticipated need to support the American SST-which 

program itself fell to the congressional axe of 1971. By that date the 

center was again well established with a variety of research projects, 

primarily in aeronautics, that necessitated its continued existence. Further, 

its major role in flight testing the upcoming Space Shuttle was already 

mapped out. 

That FRC was so well established again by 1971 stemmed from a 

variety of factors but chiefly from the aggressive policies and initiatives of 

center director Paul Bikle. In 1963, at his urging, De Beeler and senior 

FRC staffers prepared a comprehensive five-year plan for the future 

direction of the enter.^ This document served as a general guide for 

center activities through the end of the decade. The plan (Table 4) 

134 
c * I e 

L 

SERVING GEMINI AND APOLLO 

Table 4 

FRC Five-Year Research Plan, 1963: 

Continuing Activities 

Aeronautics Technology 

Studies of SST operational problems using modified service aircraft. 

Space Technology 

X- 15 flight operations (X- 15 follow-on program). 

Paresev studies." 

Active support and research on Dyna-Soar.b 

New Initiatives 

Aeronautics Technology 

Renewed military service testing, starting with F- 11 1. 

Development of a mulitpurpose airborne simulator using a modified Lockheed 

JetStar transport to simulate a wide range of aircraft, from hypersonic reentry 

vehicles to SSTs. 

Investigation of the handling qualities of light airplanes to improve general aviation 

safety. 

Space Technology 

Flight testing of M2-FI lifting body and development of supersonic lifting bodies to 

assess the low-speed handling qualities and approach and landing characteristics of 

lifting body spacecraft. 

Development of a lunar lander simulator to serve as a training device for the Apollo 

program. 

Studies of an advanced hypersonic research vehicle successor to the X- 15. 

"A kite-like landing system for spacecraft, to be discussed subsequently. 

bDyna-Soar was terminated at the end of 1963. 

emphasized continuing four on-going air and space activities while 

developing six new initiatives. Some of these, such as lifting bodies, 

continued into the 1970s. By the mid-l960s, then, the Flight Research 

Center clearly knew where it was going in the future, even if others 

elsewhere were not so certain. 

EARLY SPACE RESEARCH AT FRC 

FRC's research in support of NASA's space program began in 1959 

when, at the request of the Space Task Group, the center flew a series of 

135 
ON THE FRONTIER 

F- 104 flights to drop test versions of the Project Mercury spacecraft’s 

drogue parachute from altitudes above 15 000 meters. As a result of 

these tests, critical design problems were discovered and corrected before 

the spacecraft first flew.6 The center’s greatest early space effort, however, 

was on the planned Dyna-Soar program, the X-20A. 

Dyna-Soar, the “Round Three” after the X- 15, was a Sanger-like 

boost-glider designed to be lofted into orbit by a Titan I11 booster. 

Dyna-Soar had three major objectives: to demonstrate controlled lifting 

reentry from space and acquire data useful for the development of other 

lifting reentry spacecraft; to investigate a pilot’s ability to perform useful 

tasks in space; and to explore piloted, maneuverable reentry including 

landing at conventional airfields.’ Its general configuration was that of a 

hypersonic slender delta, a flat-bottom glider using radiative cooling. 

Under development for the Air Force by Boeing, Dyna-Soar was pushing 

technology in many areas, including high-speed aerodynamics, hightemperature structural materials, and reentry protection concepts. 

Eventually, questions over its utility, research potential, and safety forced 

cancellation of the craft in December 1963. Nevertheless, Dyna-Soar was 

a generally useful design exercise; much of the research encouraged by 

this program significantly influenced subsequent Shuttle studies. Like 

others of the X series before it, the X-20A thus acted as an important 

research focal point.’ 

The Dyna-Soar project office, in conjunction with NASA, had 

selected an FRC pilot, Milt Thompson, as the only NASA pilot to fly the 

craft. Further, FRC had complete responsibility for stipulating the 

X- 20A’s instrumentation requirements. Center engineers had already 

prepared papers on Dyna-Soar’s expected operational problems and the 

possibility of air-launching it from B-52 and B-70 mothers hip^.^ In 

early 1961, the FRC had received two “castaways,” prototypes of the 

Douglas F5D-1 Skylancer, an experimental Navy fighter that had not 

been placed in production. The F5D-1 had a wing planform very 

similar to that projected for Dyna-Soar; FRC pilot Neil A. Armstrong 

recognized that the Skylancer could be used to study Dyna-Soar abort 

procedures. How to save the pilot and spacecraft in the event of a 

launch-pad booster explosion was a problem of great concern to the 

Dyna-Soar team. The X-20A Dyna-Soar had a small escape rocket to 

kick it away from its booster, but no one really knew what kind of 

separation flight path and landing approach would best bring Dyna-Soar 

safely to earth. Armstrong developed a suitable maneuver using the 

F5D-1; it consisted of a vertical climb to 2100 meters, pulling on the 

control column until the “X-20A” was on its back, rolling the craft 

upright, and then setting up a low lift-to-drag-ratio approach, touching 

down on a part of Rogers Lake that was marked like the 3200-meter 

landing strip at Cape Canaveral. Following Dyna-Soar’s cancellation, 

136 
P L 1 

4 0 

SERVING GEMINI AND APOLLO 

Neil A. Armstrong prepares to fly a Dyna-Soar abort simulation in one of the Flight 

Research Center’s Douglas F5D - 1 Sky lancer aircraft. 

FRC continued to fly the F5Ds in sup ort of lifting body and SST studies, before retiring the aircraft in 1970. 1B 

PARESEV: A SPACE-AGE KITE 

The center’s major space research support activities concerned the 

Paresev and the Lunar Landing Research Vehicle (LLRV), developed 

and flown at the FRC in support of the Gemini and Apollo programs. 

Paresev was an indirect outgrowth of kite-parachute studies by NACA 

Langley engineer Francis M. Rogallo. The “Rogallo wing” was a diamond 

profile with a flexible covering attached to a V-shaped (point foremost) leading edge and a longitudinal keel. As with a parachute, the 

air filled out the sail-type surface, giving it its shape. In the early 1960s, 

this shape seemed an excellent means of returning a spacecraft to Earth. 

A spacecraft could streak in through the atmosphere and then, at much 

lower altitudes and subsonic speeds, deploy a stowed Rogallo wing, 

enabling the astronauts on board to fly it down to an airplane-like 

landing, obviating the need for a water landing and recovery flotilla. 

NASA engineers had begun studying how the agency could apply the 

Rogallo wing to current spacecraft projects, especially one tentatively 

designated Mercury Mark 11. 

In January 1962, Mercury Mark I1 became the Gemini program, 

America’s second major man-in-space venture, involving a two-man crew 

and encompassing extravehicular “spacewalks,” rendezvous, and docking. 

In May 1961, when Mercury Mark I1 was slowly evolving, Robert R. 

Gilruth, director of NASA’s Space Task Group, requested studies of an 

inflatable Rogallo-type “Parawing” for spacecraft. Several companies 

responded; North American Aviation produced the most acceptable 

concept and development was contracted to that company. At a 28-29 

137 
ON THE FRONTIER 

November 196 1 meeting, NASA Headquarters launched a paraglider 

development program, with Langley doing wind tunnel studies and 

Flight Research Center supporting the North American test program. 

NASA grafted the parawing scheme onto the Mercury Mark I1 program.12 

Paraglider development involved solving major design difficulties of 

stowing and deploying the wing, ensuring that the crew would have' 

adequate control over the parawing-equipped craft, and providing 

satisfactory stability, control, and handling qualities. The Flight Research 

Center's technical staff was never convinced that the scheme was workable. 

Eventually, because of poor test results and rising costs and time delays, 

the idea was dropped from Gemini in mid-1964. FRC engineers and 

pilots had believed that any vehicle so equipped might present a pilot 

with a greater flying challenge than contemporary advanced airplanes. 

They thought that NASA should acquire some sort of baseline experience before attempting development and flight of Parawing on a 

returning spacecraft. After returning to Edwards, they continued their 

discussions among themselves. 

The best way to acquire such experience, of course, was by building 

and flying a Parawing. Two who actively favored such an approach were 

center research pilots Neil Armstrong and Milt Thompson. They approached Paul Bikle, who liked the idea, but recognized that both pilots 

had heavy Dyna-Soar commitments; FRC could not spare their services 

elsewhere, even to a project as interesting as the proposed Parawing. 

Instead, Bikle called in a group of center engineers under the direction 

of Charles Richards, a team composed of Richard Klein, Vic Horton, 

The Paresev I-A Rogallo research vehicle and one of its towplanes, a Stearman sport 

biplane. 

138 
SERVING GEMINI AND APOLLO 

Gary Layton, and Joe Wilson. Bikle’s instructions were characteristically 

short and to the point: build a single-seat Paraglider and “do it quick and 

cheap.” All this took place just before Christmas 1961. The team, now 

totaling nine engineers and technicians, set to work on this “Paraglider 

Research Vehicle,” conveniently abbreviated Paresev. Seven weeks later, 

after expending $4280 on construction and materials, the team rolled 

out the Paresev I. It resembled a grown-up tricycle, with a rudimentary 

seat, an angled tripod mast, and, perched on top of the mast, a 

14-square-meter Rogallo-type parawing. The vehicle weighed 272 kilograms, 

had a height of over 3.4 meters, and a length of 4.5 meters. The pilot sat 

out in the open, strapped in the seat, with no enclosure of any kind. He 

controlled the descent rate by tilting the wing fore and aft, and turned by 

tilting the wing from side to side. NASA registered the Paresev, the first 

NASA research airplane to be constructed totally “in-house,” with the 

Federal Aviation Administration on 12 February 1962. Flight testing 

started immediately. l3 

At first, with ingrained caution, engineers tested the Paresev by 

towing it behind a utility vehicle. Technicians drove a tow vehicle up to 95 

kilometers per hour on the lakebed; the Paresev lifted into the air at 

about 65 kilometers per hour, followed by a dusty gaggle of “chase” cars 

and motorcycles. Milt Thompson, one of the two project pilots (the other 

being NASA’s Bruce Peterson), would let the plane float along a few feet 

off the ground as he gained familiarity with the vehicle. The original 

configuration had several faults. The control system had built-in lag; 

pilots used to the sensitivity of modern ‘et aircraft found that the Paresev 

flew as if “controlled by a wet n~odle.”‘~ Because cloth-covered airplanes 

often used Irish linen, the Paresev design team decided to use it for the 

wing surface. Dick Klein and Gary Layton visited a sailmaker in Newport 

Beach; he cast a quizzical eye at the material and suggested Dacron 

instead. The team stuck with linen, found it did indeed have a number of 

problems including flutter at the trailing edge, and changed to Dacron at 

a later date.15 The Paresev was difficult to fly-Thompson considered it 

more demanding than the later lifting bodies. He made several hundred 

ground tows and 60 air tows, recollecting later that “it was a lot of fun.”I6 

But it had its moments of danger, too. During one ground tow, Bruce 

Peterson got out of phase with the lagging control system and developed 

a rocking motion that got worse and worse; just as the tow truck started to 

slow, the Paresev did a wing-over into the lakebed, virtually demolishing 

the Paresev and injuring Peterson, though not seriously. 

The accident ended the days of the Paresev I; FRC technicians 

salvaged only the tripod from the wreck. They totally rebuilt the vehicle, 

this time with a much more sophisticated control system using a conventional stick and rudder system. They took the sailmaker’s advice and used 

a Dacron wing. This became the Paresev I-A. Ground tows quickly 

139 
ON THE FRONTIER 

indicated this paraglider handled better than its predecessor, and NASA 

moved to flight tests. To tow the I-A, FRC rented a Stearman biplane 

from a Tehachapi sailplane operator. Later a Cessna L- 19 Bird Dog was 

acquired on loan from the U.S. Army Reserve. The Paresev project team 

also flew a smaller wing on the I-A. During Paresev I-A tests, tow 

planes dragged it to 3000 meters before release. For a test pilot used to 

the confined but comforting environment of a supersonic jet, it was an 

eery sensation to sit out in the open, like a pre-World War I aeronaut, 

strapped in the seat. In addition to Milt Thompson and Bruce Peterson, 

Neil Armstrong, Emil “Jack” Kleuver (an Army pilot detailed to FRC), 

astronaut Gus Grissom, and Langley research pilot Bob Champine-a 

Muroc old-timer-flew the little craft. It underwent one further 

modification, as the Paresev I-B, equipped with an inflatable Geminitype wing as well. NASA ended flight tests on the Paresev in 1964, having 

completed over 100 flights.” 

The Paresev program is a good example of the Bikle low-cost 

do-it-quick approach. Originally scheduled as a two-month flight test 

project, the program became interesting enough to warrant running for 

two years. Eventually engineers evolved a useful vehicle having acceptable handling characteristics. Nevertheless, it was a big step from this 

simple technology demonstrator with a rigid and fixed wing framework 

to a stowable, inflatable parawing on an actual spacecraft that could be 

relied on to return a crew safely to Earth. At the same time that NASA’s 

Paresev was concluding so agreeably, North American’s complex Gemini 

Paraglider program had already forced a test pilot to abandon one of the 

vehicles in flight-hardly encouraging. The long process involved in 

making the relatively unsophisticated Paresev an acceptable craft indicated the magnitude of the task awaiting those developing such devices 

for spacecraft. 

NASA’s FLYING BEDSTEADS 

NASA’s major undertaking in the 1960s was the Apollo program, an 

ambitious and breakneck-pace effort to place astronauts on the moon by 

the end of the decade. It is difficult now to relive those hectic days, to 

imagine the level of activity at NASA centers around the country, the 

frantic pace of meetings, the sense of mission that pervaded the agency 

and its workers. Virtually every worker felt privileged to work for the 

agency, and even the wing-oriented NACA old-timers did their best to 

contribute to the national space effort. 

One of the many critical questions in the Apollo program was the 

descent to the lunar surface. The descent vehicle would only be operating 

in a gravity 1/6 that of Earth’s, but the airless moon dictated a strictly 

propulsion-borne descent, not an aerodynamic descent. Grumman was 

140 
SERVING GEMINI AND APOLLO 

the subcontractor for the landing vehicle, the LEM, later shortened to 

LM.* Nobody wanted the first lunar landing, with its attendant high pilot 

workload and psychological stress, to be also the first time an astronaut 

team flew a lunar landing descent profile. Some sort of exotic simulator 

was needed to give the crew some useful experience before they tackled 

the task of setting down on the moon. There were several possible ways 

of doing this. One would be an electronic simulator. Another would be a 

free-flight test vehicle. Yet a third would be a tethered device, suspended 

beneath some sort of framework. NASA decided to be conservative and 

followed all three routes. The most ambitious of the three was the 

free-flight vehicle. As might be expected, this was the Flight Research 

Center’s contribution to Apollo. 

The FRC staff conceived the idea for a free-flight lunar landing 

simulator. In early 1961, Hubert Drake had convened a group of FRC 

engineers to investigate simulating a lunar landing. Drake contacted Walt 

Williams, then associate director of the Manned Spacecraft Center; 

Williams offered his enthusiastic support, recommending that FRC 

propose such a vehicle to NASA Headquarters. At the same time, 

unknown to the FRC group, Bell Aerosystems Company (heir of Bell 

Aircraft Corporation, which had built so many of the early X-series 

aircraft) was also examining ways of building a free-flight simulator. 

When Drake and FRC engineers Gene Matranga and Donald Bellman 

learned from NASA Headquarters that Bell was interested, they invited 

company representatives to FRC for consultation; this culminated in a 

$50 000 study contract to Bell, which FRC awarded in December 1961. 

At the time, FRC was thinking of the vehicle primarily for research, 

rather than as a training aid. 

At the same time, Langley Research Center was supporting a much 

less ambitious concept involving a tethered rig. When constructed, the 

large gantry (120 meters long, 75 meters high) supported 5/6 of the test 

vehicle’s weight. Rockets supported the remaining 116. The Langley 

Lunar Landing Research Facility cost $3.5 million and started operations 

in June 1965. By that time, FRC had already amassed considerable flight 

experience with its own lunar landing simulator, the remarkable Lunar 

Landing Research Vehicle, LLRV.” 

Ajet engine supported 5/6 of the LLRV’s weight; rockets lifted the 

remainder, simulating the descent propulsion system of an actual lunar 

lander. Attitude control thrusters allowed the pilot to control the vehicle; 

aerodynamics played no part. It was not a new idea, but an old idea 

serving a new purpose. Aircraft companies had built and flown similar 

vehicles, dubbed “flying bedsteads,” to acquire information needed for 

*Lunar Excursion Module, later just Lunar Module. 

14 1 
e 

ON THE FRONTIER 

designing vertical-takeoff-and-landing (VTOL) aircraft. Dr. A. A. Griffith, 

a pioneer in British VTOL technology, had built the first such rig, 

powering it with a pair of Rolls Royce Nene turbojets. Such rigs 

invariably had an open framework supporting the pilot, his instrumentation, 

the fuel system, the engines, and a variety of “puff pipes” running hither 

and yon to control the attitude of the vehicle. Griffith‘s “Flying Bedstead” 

first flew in August 1954, gaining a great deal of attention in the aviation 

and popular press. FRC’s engineers naturally considered this vehicle 

when conceiving the LLRV.” 

Bell was the only firm in the United States that had a great deal of 

experience in the design and construction of VTOL aircraft using jet lift 

for takeoff and landing. FRC’s engineers consulted with Bell personnel 

before drawing up the specifications for their vehicle. In early 1962, 

following award of the Bell study contract, Donald Bellman (head of the 

project), Gene Matranga, and Lloyd Walsh (FRC’s contracting officer) 

ventured to Bell to interest the company in fabricating such a vehicle for 

NASA. While at Buffalo, they rode company helicopters on simulated 

lunar descents; stopwatch and notepads in hand, they quickly learned 

that a helicopter could not match the expected descent rates and paths of 

a jet-lift lander. The tests quickly silenced those who thought NASA 

could simulate the lunar landing mission aerodynamically by using 

helicopters. Following the Buffalo visit, Bellman passed along their 

tentative findings to Walt Williams at Houston. Williams endorsed the 

concept. Out of this came support from the Manned Spacecraft Center 

and NASA Headquarters. On 1 February 1963 NASA awarded Bell a 

$3 610 632 contract for the design and fabrication of two lunar landing 

research vehicles capable of taking off and landing under their own 

power, attaining an altitude of 1200 meters, hovering, and horizontal 

flight. Bell had 14 months in which to build and deliver the first vehicle, 

with the second to follow 2 months later. NASA intended using them for 

studies of piloting and operational problems during the final phase of a 

lunar landing and the initial phase of a lunar takeoff. The tests would 

permit study of controls, pilot displays, visibility, propulsion control, and 

flight dynamics. Each ‘LLRV would carry 70 kilograms of research 

equipment.20 

Bell unveiled the first of the two LLRVs during ceremonies at its 

Wheatfield, New York, plant on 8 April 1964. Bell’s Kenneth L. Levin 

oversaw the development. FRC’s C. Wayne Ottinger served as NASA 

resident representative. The completed LLRV weighed 1680 kilograms, 

stood slightly more than 3 meters high, and had four aluminum truss legs 

spread 4 meters. A General Electric CF-700-2V turbofan engine 

provided 18 700 newtons (4200 lb) thrust, enough to boost the LLRV to 

altitude. Then the engine would automatically adjust to support 5/6 of 

142 
SERVING GEMINI AND APOLLO 

the vehicle’s weight, and the pilot would use two lift rockets capable of 

modulation from 440 to 2200 newtons (100 to 500 lb) thrust for 

controlling the “lunar descent.” The lift rockets burned hydrogen 

peroxide. Sixteen smaller rockets, arranged in eight pairs, controlled 

pitch, yaw, and roll. To permit the turbofan engine to maintain vertical 

thrust when the vehicle assumed other than a horizontal attitude, Bell 

gimballed the engine at the apex of the vehicle’s legs. The LLRV had 

six backup rockets capable of 2200 newtons (500 lb) thrust for emergency use if the turbofan engine quit. The pilot sat out in the open, 

behind a Plexiglas shield, on an emergency “zero-zero” ejection seata wise precaution, as things turned out. The LLRV could remain aloft 

14 minutes at full thrust, though safety considerations dictated a more 

prudent limitation of 10 minutes. It used an electronic “fly-by-wire” 

(FBW) control system connected to a conventional aircraft-type center 

stick for pitch and roll control and “rudder” pedals for yaw control. 

There were no aerodynamic control surfaces. The system provided 

direct electronic control-with no mechanical linkages, even as a backup 

safety system-of the attitude rockets. FBW also simulated the actual 

vehicle motions and control system response that an astronaut could 

expect to encounter while piloting a descending lunar module. 

After unveiling the surprising craft to the press, Bell sent both 

LLRVs to Edwards in partially disassembled and incomplete condition to 

expedite NASA’s installation of instruments, for FRC technicians believed they could complete the craft more quickly than could Bell. The 

two LLRVs arrived at the Flight Research Center on 16 April 1964, and 

center personnel immediately set to work preparing the first for flight.*l 

By September 1964, the FRC had LLRV #1 ready for its first trials, 

mounted on a fixed “tilt table” constructed by the center’s Aircraft 

Modification and Repair group. Joe Walker first tested out the craft in 

this manner. It had complete freedom of movement, being restricted 

only from flight. The tilt table tests proceeded smoothly; by the fall of 

1964, the LLRV research team was ready for free-flight trials. Test 

operations were set up at Edwards’ South Base, scene of the old 

High-speed Flight Station. On 30 October 1964 center test pilot Joe 

Walker took the craft on its first flight, making three separate liftoffs and 

landings, reaching a peak altitude of three meters, and remaining aloft 

for a total free flight time ofjust under one minute. The craft took off, as 

Walker subsequently described it, “just like going up in an elevator,’’ At 

liftoff, with the CF- 700 wailing, the pilot maintained proper attitude by 

firing short bursts of reaction controls; they hissed loudly, swathing the 

craft in peroxide steam and enhancing the Rube Goldberg appearance. 

By the end of the year, Walker was joined by Donald Mallick, a new FRC 

pilot who had transferred from Langley. Mallick completed his checkout 

143 
dj a 

ON THE FRONTIER 

on 9 December. Over the next year, LLRV #1 continued its flight 

program. By the end of August 1966, it had completed 175 flights, flown 

by WaIker, Mallick, and the Army’s Jack Kleuver. 

In preparation for an LLRV training program for the Apollo 

astronauts at Houston, Manned Spacecraft Center research pilots Joseph 

Algranti and H. E. “Bud” Ream checked out in the strange vehicle. On 11 

March 1966, piloted by Don Mallick, LLRV #1 flew with a three-axis side 

arm controller, making it comparable to the actual Grumman LM control 

system. NASA also moved the LLRV’s control panel from the center of 

the cockpit to the right side, again matching the LM configuration, and 

planned to reduce the amount of pilot visibility to give the craft the same 

visual characteristics as the lunar lander. In January 196’7 Jack Kleuver 

completed FRC’s first flight in LLRV #2, which had an’enclosed cockpit 

like the LM. LLRV #2 completed 5 more flights and #1 ran its total up to 

198 before the FRC concluded its program on the two vehicles in the 

winter of 1966. By this time, the LLRVs had flown as long as 9% minutes 

and attained altitudes nearing 240 meters.22 

Joseph Walker pilots the first lunar landing research vehicle (LLRV) during tests at 

Edwards’ South Base. 

144 
a 

SERVING GEMINI AND APOLLO 

FRC shipped LLRV #1 to Houston on 12 December 1966 and 

followed with #2 on 17 January 1967. Kleuver flew LLRV #1 at Houston’s 

Ellington AFB in March 1967. Afterward, Joe Algranti and Bud Ream, 

who would act as instructor pilots for the astronauts, also flew the craft. 

A month later Robert R. Gilruth, director of the Manned Spacecraft 

Center, in an official commendation of the LLRV Flight Research Center 

project team, said the flights at Edwards had “yielded important information on vehicle handling qualities and piloting techniques and procedures necessary for a successful lunar landing. . . . The LLRV program 

has and will continue to contribute much to the United States’ efforts for 

a manned lunar landing.”23 

Gilruth’s concluding remarks referred to an extension of the twovehicle LLRV program. In mid-1966, the Manned Spacecraft Center had 

ordered three more lunar landing simulators from Bell, these being 

designated LLTVs: Lunar Landing Training Vehicles. Each cost about 

$2.5 million. Incorporating modifications that resulted from experience 

with the LLRVs, the LLTV weighed 1860 kilograms and could attain an 

altitude of 120 meters. The cockpit display and control system was modeled on the lunar module, and the pilot’s visibility was restricted to 

match what the LM would offer. The first LLTV arrived at Houston in 

December 1967 and first flew 8 October 1968. The Manned Spacecraft 

Center modified the two original LLRVs as LLTV aircraft as well; they 

became LLTV-A1 and A2. The new vehicles ordered straight from Bell 

became the LLTV-B1, B2, and B3. Houston’s pilots made the initial 

LLTV flights at Houston and acted as instructor pilots to the astronauts. 

Manned Spacecraft Center quickly evolved an astronaut training program. 

Potential LM crewmen first went to helicopter school for three weeks, 

then to Langley’s Lunar Landing Facility, then on to 15 hours in a 

ground simulator, and finally to the LLTVs, which they flew from nearby 

Ellington AFB.24 

The LLTVs proved extremely useful. Indeed, as astronaut chief 

Donald “Deke” Slayton noted, there was “no other way to simulate moon 

landings except by flying the LLTV.”25 All prime and backup commanders of lunar landing missions practiced on the LLTV-A and B vehicles, 

and a number of other astronauts flew them. Gene Cernan completed 

the last LLTV flight on 13 November 1972. Commenting to newsmen 

following an LLTV training flight on 16 June 1969, a month before 

liftoff of ApoZZo 11, mission commander Neil Armstrong remarked: “We 

are very pleased with the way it flies. . . . I think it does an excellent job of 

actually capturing the handling characteristics of the lunar module in the 

landing maneuver. . . . we’re getting a very high level of confidence in 

the overall landing rnane~ver.’’~~ 

Houston’s LLTV operations were not without difficulty. In fact, 

three of the five vehicles crashed. On 6 May 1968 Neil Armstrong took 

145 
a 1 a 

ON THE FRONTIER 

off in LLTV- A1 , the former LLRV # 1. While hovering 10 meters above 

the ground, the vehicle suffered a loss of helium pressure in the 

propellant tanks, causing shutdown of its attitude control rockets. It 

started nosing up and rolling over, and Armstrong immediately ejected. 

His zero-zero seat kicked him away from the stricken craft, which tumbled 

into the ground and exploded as the astronaut safely descended by 

parachute. It was a sad fate for a pioneering flight craft. On 8 December 

1968 gusty winds forced LLTV-Bl out of control; MSC pilot Joe 

Algranti safely ejected just one second before the wobbling simulator 

crashed. Finally, on 29 January 1971, LLTV-€32 suffered an electrical 

failure that caused loss of attitude control. MSC pilot Stu Present 

abandoned this sick bird safely.27 

The LLRV-LLTV program is a remarkable example of how the 

Flight Research Center’s bias toward free-flight testing helped NASA 

achieve a spectacular success: the first manned lunar landing. Naturally, 

when discussions turned to putting astronauts on the moon, this bias had 

triggered a desire on the part of Flight Research Center engineers to 

build a specialized flight research testbed. Other centers, dominated by 

ground-based laboratory thinking, had favored less radical, more traditional and less satisfactory methods, such as fixed simulators and semimobile 

rigs. Combination of these methods produced the successful lunar 

landings, which went off flawlessly. Two of these craft still exist: the 

LLTV-A2 and the LLTV-BS. It is difficult now to conceive of such 

strange and grotesque hardware making a worthwhile contribution to 

any development effort; but that the LLTVs did contribute, and 

handsomely, is beyond dispute. 

By the time Neil Armstrong set foot on the moon, however, the 

Paresev and LLRV programs were rapidly fading memories at Edwards. 

FRC was busy on other space-related projects in an area of traditional 

FRC interest: hypersonic lifting reentry from space. At the heart of this 

effort was a strange group of test vehicles, the lifting badies. They come 

as a t to the early days of “Round TWO” and “Round Three” and 

as a to the Space Shuttle. 

146 
8 

Prelude to Shuttle: The Lifting Bodies, 

1962 - 19’76 

During the late 1950s and early 1960s, two camps emerged among 

those studying reentry from space. One group favored so-called “ballistic” 

reentry, literally dropping out of orbit and transiting the atmosphere 

like a plunging stone. The other camp favored “lifting” reentry, a longer 

passage from space to Earth that would enable a crew to fly a spacecraft 

to a conventional landing at an airfield. A lifting reentry spacecraft was a 

far more demanding-but potentially far more useful-technology than 

a ballistic “capsule.” Designers would have to develop a configuration 

with adequate structural strength to withstand the rigors of a missile-like 

launch, with a reusable or refurbishable thermal protection system for 

reentry, and with adequate hypersonic, supersonic, transonic, and subsonic flying qualities-no mean feat. The X-20A Dyna-Soar project was 

a premature attempt to develop such a craft. 

Dyna-Soar was not the only lifting reentry approach to orbital flight; 

there were also weird, wingless shapes known, for want of a better title, as 

“lifting bodies.” The lifting body concept dated back to the blunt-body 

studies of H. Julian “Harvey” Allen, an imaginative engineer at Ames 

Aeronautical Laboratory. Allen conceived the blunt body theory in 1951. 

Together with Alfred Eggers, Allen concluded that a ballistic missile 

warhead having a blunt, rounded nose (as opposed to a pointed shape) 

would better survive the intense heat generated as it entered the atmosphere from space at near-orbital velocities. The blunt shape produced 

a strong, detached bow shock wave that, in effect, gave the following 

warhead excellent thermal protection. Allen’s work remained highly 

classified, but the fruits of it appeared on the Atlas missile’s deadly nose. 

Necessarily the blunt body had a very low lift-to-drag ratio, far less 

than 1. It flew a ballistic descent path having a minimal “cross-range 

footprint.” Allen and Eggers, together with Clarence Syvertson, George 

Edwards, and George Kenyon, recognized that designers might be able 

to combine the blunt body with a manned orbital vehicle in such a way 

147 
ON THE FRONTIER 

that it had an acceptable lift-to-drag ratio, on the order of 1.5. This could 

reduce reentry g loadings from the 8 g experienced by a blunt body to 1 g 

and give a cross-range footprint in excess of 2400 kilometers from the 

initial point of atmospheric entry. Eggers deduced that one desirable 

shape for such a vehicle would be a modified half-cone (flat on top) witha 

rounded nose to reduce heating. Working at Ames, Eggers, Syvertson, 

Edwards, and Kenyon refined the concept in 1958, deriving the M2 

configuration, a 13” half-cone with a rounded nose having a lift-to-drag 

ratio of 1.4 at hypersonic speeds. At subsonic speeds, however, its 

woefully inadequate stability characteristics made it prone to tumble end 

over end. Eventually the Ames engineers “boat-tailed’ the top and bottom 

of the shape, giving it an airfoil cross-section and curing most of the 

stability difficulties. This final M2 version had a protruding canopy and 

twin vertical fins-the fins earning it the sobriquet “M2 Cadillac.” By 

1960 the lifting body work at Ames was far from fruition, but engineers 

had chosen a basic shape. (See lifting bodies in the color photo section at 

the end of this chapter.) 

Ames was not the only NASA center engaged in lifting-body studies. 

The High-speed Flight Station did not have the hypervelocity tunnels, 

guns, and shock tubes needed for such research, but the staff kept in 

touch with colleagues at the larger centers and were aware of what was 

going on. One night over drinks at the Antelope Valley Inn, Walt 

Williams prophetically suggested to Eggers that the HSFS could build a 

piloted M2 shape for low-speed stability and control tests, launching it 

from a B-52. The HSFS engineers would make their own contributions 

soon enough, originating the flight-test programs for the lifting bodies. 

At Langley, engineers favored a more traditional approach over sawing a 

cone in half. They opted for modified delta configurations. Eventually, 

as a result of the work of Eugene S. Love, Langley devolved the shape for 

the HL-10-HL standing for horizontal lander. It first appeared on 

Langley drawing boards in 1962 as a manned lifting reentry vehicle. 

Though still working on Dyna-Soar, the Air Force considered other 

lifting reentry schemes and in the early 1960s, commissioned a series of 

studies that eventually spawned the Martin SV-5D shape, a configuration between the cone-like M2 and the modified delta HL-10. In sum, 

then, the Ames M2, Langley HL-10, and Air Force-Martin SV-5D 

shapes were all outgrowths of the same climate of research that had 

created the Dyna-Soar program; their roots were in “Round Three” 

thinking. 

THE FIRST LIFTING BODY 

Robert D. Reed, an FRC Research Division engineer, was fond of 

building flying models. While recognizing that models are limited in the 

148 
x1 e 

THE LIFTING BODIES 

range of information they can return, he knew they could validate basic 

stability and control characteristics of a new configuration. Reed had 

followed with interest the Ames work on the M2, noting that while it had. 

potentially excellent hypersonic characteristics, doubts existed that the 

M2 could successfully fly to a landing because of difficulties in handling 

at transonic and subsonic speeds. Other NACA engineers had suggested 

in the 1958 HSFS research assessment that NACA develop low-speed 

testbeds of proposed hypersonic shapes to determine their landing 

behavior. In February 1962, Reed built a 60-centimeter model of the M2, 

which he launched from a larger radio-controlled “mothership” having a 

150-centimeter wingspread-a typical FRC approach scaled down in size. 

Reeds wife filmed some of the flights to show center director Paul Bikle, 

De Beeler, and Alfred Eggers. Reed also flew small lifting body models 

down the corridors at FRC, causing raised eyebrows among skeptics. But 

Eggers promised the use of wind tunnels at Ames, and Bikle authorized a 

six-month feasibility study of a cheap, manned, lightweight M2 glider, 

the “next step” suggested by Reed-who also flew sailplanes as a hobby.’ 

In September 1962 Bikle authorized design and construction of a 

manned M2 glider. Victor Horton headed the effort, assisted by Dick 

Eldredge and Dick Klein. FRC engineers built the tubular steel structure, 

and Gus Briegleb of the Sailplane Corporation of America built the 

plywood outer shell. At first, Reed, Horton, Eldredge, and Klein wished 

to test various lifting body shapes, including M1, M2, and a lenticular 

“flying saucer” concept. The M2 seemed the most practicable, however, 

and was the only one the FRC proceeded with. Technicians set aside floor 

space in a hangar, walled it off with canvas, and put up a sign reading 

“Wright’s Bicycle Shop.” The project team drew on many other FRC 

staffers for assistance, especially the large local NASA community of 

aircraft “homebuilders,” mostly members of the Experimental Aircraft 

Association. Bikle ran the project out of local funds on a nickel-and-dime 

basis, because he feared he could not secure Headquarters support 

rapidly enough to permit a quick development program. Bikle’s concern 

over complicating the project by working through the system was well 

founded: one major aircraft company informed the FRC M2 team that it 

would have cost $150 000 for the firm to build such a vehicle. By using 

in-house funding and exacting cost control, FRC engineers kept expenditures on the design and fabrication of the M2 glider, including support, 

beneath $30 000. Briegleb‘s own construction team, consisting of three 

mechanics and a draftsman working at El Mirage Dry Lake, built the 

mahogany plywood body shell (23 millimeters thick) in 120 days. The 

FRC team had stipulated that the body shell weigh less than 135 

kilograms; Briegleb‘s team managed to complete it at 124 kilograms.* 

The FRC-Briegleb team finished the M2 glider, which the FRC 

designated the M2-F1, early in 1963. A tubby vehicle, it measured 6 

149 
* 

ON THE FRONTIER 

meters long and 3 meters high, with a width of 4 meters. It had two 

vertical fins, just like the earlier Ames “M2 Cadillac” study, and stubby 

elevons were mounted on the fins. The body had trailing edge flaps for 

trimming purposes and landing gear wheels from a Cessna 150 airplane. 

With its pilot, the M2-F1 weighed 516 kilograms. The pilot sat under a 

large bubble cockpit; though at first the craft had no provisions for 

emergency ejection, the FRC later added a lightweight Weber rocketpropelled zero-zero seat. Later the craft also had a 10’70-newton (24-lbthrust) solid-fuel rocket developed by the Naval Ordnance Test Center 

at nearby China Lake to assist in the prelanding “flare” maneuver if this 

became necessary. The craft was trucked to Ames for low-speed tunnel 

testing in the 40 x 80 ft tunnel. The tunnel tests, completed in March 

1963, were very encouraging. NASA project pilot Milt Thompson often 

sat in the cockpit of the M2-F1 during the studies, “flying” the 

rigidly mounted craft in the cavernous maw of the full-scale tunnel. 

Satisfied, Ames gave the shape its blessing, and FRC took it back to 

Edwards in preparation for its first flights, a series of Paresev-like ground 

tows. 

Strange enough already, the M2-F1 program now took a real turn 

toward the bizarre. Obviously, the shape had a lot of drag, requiring a 

tow vehicle with great power and speed. NASA’s general-purpose trucks 

and vans just could not do the job; a specialized, high-performance tow 

car was needed. The solution did not take long. Out in the desert lived a 

number of racing aficionados, many of whom worked at FRC. After 

consulting with them, the FRC M2 team bought a stripped-down Pontiac 

convertible with the largest engine available, a 4-barrel carb, and a 

4-speed stick shift, capable of towing the M2 to 1’7’7 kilometers per hour 

in 30 seconds. Then the team turned it over to “funny car” expert Mickey 

Thompson’s shop in Long Beach, where technicians fine-tuned the 

engine, added rollbars, installed radio equipment, turned around the 

right passenger bucket seat to face aft, and removed the rear seats, 

installing another bucket seat for a second observer facing sideways. 

. Fearful lest a critic hastily conclude that this was somebody’s private 

toy paid for with government funds, the team quickly painted “National 

Aeronautics and Space Administration” on the sides and sprayed the 

hood and trunk high-visibility yellow, like any other flight-line vehicle.* 

The NASA engineers added a tow rig and some airspeed measuring 

equipment, and then took it to the Nevada desert, with its (then) 

anything-goes speed limit to calibrate the speedometer-just like any 

*Toward the end of 1963, NASA shipped the Pontiac to Langley for tests at Wallops Island. “No 

longer,” mourned the X-Press, “can we drive along the lakebed and pass the airplanes in flight.” 

150 
THE LIFTING BODIES 

other research airplane. Team members fondly recollect the strange 

head-shaking stares of California and Nevada highway patrolmen as the 

exotic auto rumbled along, driven by Walter Whiteside, engine exhausts 

roaring. Its gasoline mileage wasn’t good-just six kilometers per gallon. 

Finally, by the spring of 1963, all was ready. Milt Thompson ventured out 

on the lake, the M2-Fl rigged behind the Pontiac on a tow line for its 

first excursion into .the air.3 

The M2-F1 completed its first ground tows on 5 April 1963 and 

made 45 others by the month’s end. From then until the first air tows, the 

little lifting body made over 100 tows, an accumulated air time of nearly 

four hours. Generally speaking, the M2-F1 had acceptable flying 

qualities, warranting its being air-towed to altitude and released; but 

Thomas Toll, FRC’s chief of research and one of the men responsible for 

the X-15 concept, had serious misgivings. He became especially concerned after Thompson’s first flight, when the pilot encountered a 

dangerous lateral oscillation. Nevertheless, Bikle went ahead and approved air tows. FRC had a Douglas C-47 “Gooney Bird” assigned for 

general duties. The C-47, the military version of the legendary DC-3, 

had been an excellent glider tug during World War I1 in such campaigns 

as Sicily and Normandy. Vic Horton of the FRC’s M2 team scrounged up 

a C-47 tow mechanism from a junkyard. The team installed it on the plane, 

and on 16 August 1963 Milt Thompson piloted the little lifting body as 

the center’s C-47 towed it off the lake. On this and other flights, the 

C-47 generally climbed at about 190 kilometers per hour to over 3000 

meters, the M2-F1 trailing on a 300-meter towline. The towplane would 

release the glider above its intended landing spot on Rogers Lake, and 

Thompson would guide the rapidly sinking craft to a touchdown about 

two minutes after release, landing at 137- 145 kilometers per hour. On 3 

September FRC unveiled the craft to aviation news reporters. The lifting body concept at once became a hot journalistic item.* 

The first flights of the M2-F1 had proved that the lifting body 

shape could fly. As early as mid-April 1963, Bikle was convinced enough 

to bring NASA Headquarters into his confidence. He told Milton Ames, 

NASA’s director of space vehicles: “The lifting-body concept looks even 

better to us as we get more into it. We also recognize a rising level of 

interest in the concept at Ames and at Langley.”’ There was a rising level 

of interest on Capitol Hill as well, as word got back to Washington. By 

mid-April 1963, many congressmen were quizzing NASA Headquarters 

officials on the M2 flight program, and causing consternation among 

some Department of Defense officials who apparently had no idea that 

the M2 was flying. Some congressmen feared the low-budget M2 might 

soar overnight to a major multi-billion-dollar post-Apollo development 

program; others later suspected that the program was a way for NASA to 

151 
ON THE FRONTIER 

circumvent the decision to cancel Dyna-Soar. Hugh Dryden and OART’s 

Raymond L. Bisplinghoff defended the FRC effort, and the M2 program 

continued.6 

At Edwards, seven other pilots checked out in the airplane; NASA 

test pilots Bruce Peterson, Donald Mallick, and Bill Dana; and the Air 

Force’s Chuck Yeager, Capt. Jerauld Gentry, and Lt. Col. Donald Sorlie. 

Colonel Yeager clambered out of the craft after his first flight exclaiming 

“She handles great!” He hoped to use similar vehicles, powered by small 

jet engines, as lifting body simulation trainers at the Aerospace Research 

Pilots School, which he commanded. 

Eventually the little M2 - F 1 completed approximately 100 flights 

and 400 ground tows before retirement to the Smithsonian’s National Air 

and Space Museum (it is now held in storage at Dryden for the museum). 

FRC did have to make some modifications to the craft. On one flight, 

NASA’s Bruce Peterson landed with sufficient force to shear off the 

landing wheels, and the M2 - F 1 sustained minor damage; during the tow 

to altitude, the automobile-type shock absorbers had become chilled, and 

the cold hydraulic fluid simply failed to function properly on touchdown. 

NASA replaced the Cessna 150 landing gear with more rugged gear 

from a Cessna 180. On two other flights, Jerauld Gentry became involved 

in some extremely hazardous rolling maneuvers. On one occasion, Vic 

Horton glanced out of the C-47 in time to see Gentry and the M2-Fl 

rolling inverted on the towline; for several seconds, the launch crew in 

the C-47 did not know if the errant lifting body had ploughed in. When 

they next saw it, however, it rested safely on the lake: Gentry had cast off, 

stabilized the M2-F1, flared, and landed-just another close call. Not 

wishing to take further chances, Bikle shut down the M2-Fl program. It 

had served its purpose: it proved that the lifting body shape could fly 

and encouraged further research with supersonic, rocket-powered lifting 

bodies, to determine if the shapes so desirable for hypersonic flight could 

safely fly from supersonic speeds down to landing, through the still tricky 

area of transonic trim changes. When the tubby M2-F1 completed its 

last air-tows in August 1964, work was already well along on two 

“heavyweight” aluminum follow-ons-the M2-F2 and the HL- 10, both 

Northrop products.’ 

ESTABLISHING A JOINT LIFTING BODY PROGRAM 

With the encouragement afforded by the M2-F1, FRC pressed 

forward on its lifting body studies, which eventually led to the Northrop 

M2-FZ (and later the M2-F3) and the Northrop HL-10. Air Force 

interest resulted in formation of a joint NASA-Air Force lifting body 

program. The Air Force Flight Test Center and the NASA Flight 

152 
* 

THE LIFTING BODIES 

Research Center issued a Memorandum of Understanding on the 

program in April 1965. 

Early in 1963, as the M2-F1 took shape at Edwards and El Mirage, 

Dale Reed’s M2 team had preliminary studies under way on an airlaunched, “mission weight,” rocket-propelled, mach 2 lifting body using 

off-the-shelf systems and equipment. This research vehicle, informally 

dubbed “Configuration 11,” could return useful information on the 

supersonic and transonic behavior of such craft, piloting problems and 

workloads, and approach and landing characteristics of a “mission 

weight” lifting body. The earlier lightweight M2-F1 had a “wing 

loading” only 115 of that expected with a fully developed and operational 

space-rated lifting body. Oddly, NASA recognized from the outset that 

the lightweight lifting body would be considerably more difficult to land 

than the heavyweights. Even though both had the same lift-to-drag 

ration, the lightweight M2 had an inherently shorter time between the 

pilot’s landing flare and touchdown than the heavyweight would have. 

This increase in time available before touchdown was desirable from a 

piloting standpoint, but the heavyweight vehicles also landed much 

faster. The FRC M2 team had decided to proceed with the lightweight 

M2 tests, even though the vehicle would be difficult to fly, because its low 

touchdown speed (around 137 kilometers per hour) reduced the risk of 

pilot injury.’ 

Bikle’s almost-covert M2 operation at Edwards proved a big success 

in boosting the lifting body concept. The flight test results encouraged 

greater participation by other NASA centers and Headquarters through 

the Office of Advanced Research and Technology under NASA Associate Administrator Raymond Bisplinghoff. On 15 and 16 September 

1964, just after the end of the M2-F1 program, Bisplinghoff and some 

of his staff met with Paul Bikle and the M2 team at Edwards. What came 

out of this meeting was a directive to the NASA center directors asking 

that they document “existing research effort on entry vehicles of the 

lifting-body class,” with a view toward possible construction of a hypersonic 

lifting body. OART now strongly supported the lifting body research 

program at Edwards; Bisplinghoff wrote, “I believe it is essential that we 

have a strong in-house research effort covering all the technical problem 

areas of importance to lifting-body vehicle design and ~peration.”~ 

By this time the “heavyweight” program was under way. In February 

1964 FRC solicited proposals from 26 firms for two heavyweight, lowspeed, lifting body gliders. NASA would test them in the full-scale Ames 

wind tunnel and also air-launch them from a B-52 flying at 13 700 

meters. The firms had five weeks to submit proposals. OART would supervise the program, with Ames, Langley, and FRC participating. One glider 

would be an M2, and the other would be Langley’s own proposed 

HL- 10 modified delta shape. Only five companies submitted proposals; 

153 
ON THE FRONTIER 

FRC selected the Norair Division of the Northrop Corporation to build 

the vehicles. On 2 June 1964 the FRC awarded a fixed-price contract to 

Northrop for the fabrication of the M2 and HL- 10 heavyweight gliders 

for $1.2 million apiece. Northrop would deliver the MZ-FZ in the late 

spring of 1965, with the HL- 10 following six months later.” The lifting 

body program had moved into its next phase. FRC and Headquarters still 

favored going beyond gliders to powered supersonic lifting body trials; in 

early August 1964 Bikle, Bisplinghoff, and Bisplinghoff s deputy Alfred 

Eggers agreed on incorporating provision for XLR- 1 1 rocket engines in 

the two new gliders.” 

What most influenced Bikle and the FRC project team in their 

selection of Northrop were the elements of simplicity and costs. Northrop, 

a company in the midst of a highly successful “private” fighter venture 

(the F-5 program), assured FRC that it could build the two gliders 

cheaply. Richard Horner, who had worked with Bikle first at Edwards, 

then from NASA Headquarters, was now executive vice president of 

Northrop. The two men dispensed with all unnecessary paperwork and 

red tape. The result of this simplification was that the vehicles, which one 

industry spokesman had predicted could cost $15 million apiece, wound 

up costing just $1.2 million apiece, unheard of for complex research 

airplanes. Bikle assigned FRC engineer John McTigue as NASA program manager, while Northrop assigned Ralph Hakes as Norair’s program manager. The two men devised a Joint Action Management Plan to 

minimize paperwork, to minimize the number of employees working on 

the project, to make decisions by individuals and not by committees, to 

locate the project in one area where all necessary resources could be 

easily and quickly directed to it, and to fabricate the vehicle using a 

conservative design approach. As Hakes recalled, 

We never had more than a handful of engineers.. . . They were all 

twenty-year men who had worked to government specifications all their lives 

and knew which ones to design to and which to skip. McTigue’s people and 

ours would talk things over and decide jointly what was reasonable compliance with the specifications. Decisions were made on the spot. It didn’t 

require proposals and counter-proposals. l2 

Because of his long Air Force association, Paul Bikle always worked 

closely and effectively with his Air Force Flight Test Center counterparts, 

much as Walt Williams had before him. He recognized that, like the 

X- 15, the lifting body program required some sort of joint operations 

agreement because the program was getting too large for NASA to 

manage and operate alone. He knew that the NASA-Air Force-contractor 

flight testing relationship was a close one; as with the NACA in the late 

1940s at Muroc, there were few if any disagreements among the 

154 
a 5 L1 * 

THE LIFTING BODIES 

working-level personnel. Such disagreements as existed were imposed 

from above. Bikle saw that the Air Force and NASA had similar interests 

in the lifting body concept; over the early spring of 1965, he met with 

Maj. Gen. Irving Branch, commander of the Air Force Flight Test Center 

at Edwards. Out of these meetings came a Memorandum of Understanding on 19 April 1965. The memo drew on previous X- 15 program 

experience, alluding to the similarities between the programs and the 

excellent working relationships that had existed between Air Force and 

NASA personnel assigned to the X- 15 program. The memo created the 

Joint FRC/AFFTC Lifting Body Flight Test Committee composed of 10 

members: director of FRC (chairman), commander of the AFFTC 

(vice-chairman), NASA and Air Force pilots, NASA and Air Force 

engineers, NASA and Air Force project officers, NASA instrumentation 

representative, and medical officer from the Air Force. 

The joint flight test committee had overall responsibility for the test 

program; it also assumed responsibility for all outside relations and 

contacts. FRC had responsibility for maintenance, instrumentation, and 

ground support of the craft, while the AFFTC assumed responsibility for 

the launch aircraft, support aircraft, medical support, the rocket power plant, 

and the pilot’s personal equipment. AFFTC and FRC assumed joint 

responsibility for planning research flights, analyzing flight data, test 

piloting, range support, and overall flight operations.’ Bikle and Branch 

issued the memo two months before Northrop rolled out the M2-F2. 

But the M2-F2 and the HL- 10 were no longer the only “heavyweights” 

under construction. A year and a half later, on 11 October 1966, the 

AFFTC and FRC amended the memo to cover NASA participation in an 

Air Force-sponsored lifting body program, the Martin SV-5P. l4 

The Martin SV-5P had a complex genesis. In 1960 the Air Force 

had begun examining manned, maneuverable, lifting body spacecraft as 

alternatives to the ballistic-type orbital reentry concepts then in favor. 

This investigation became Project START (Spacecraft Technology and 

Advanced Reentry Tests), though this name emerged only much later. 

START involved a three-phase program, with ASSET (AerothermodynamidElastic Structural Systems Environmental Tests), PRIME (Precision 

Recovery Including Maneuvering Entry), and PILOT (Piloted Lowspeed 

Tests) as its eventual constituents. 

In May 1961, the Air Force Flight Dynamics Laboratory awarded the 

McDonnell Aircraft Corporation a contract for a suborbital lifting body 

reentry vehicle called ASSET. The craft measured over 1.5 meters long 

and generally resembled the canceled X-20A. McDonnell built six of 

these, launching them down the Eastern Test Range from Thor-Delta 

and Thor boosters between September 1963 and March 1965. These 

shapes reached speeds between 16 000 and 21 700 kilometers per hour 

155 
6 

ON THE FRONTIER 

while making lifting reentries from 60 000 meters over the South 

Atlantic. All the vehicles survived reentry, though some were lost at sea 

before recovery crews could pick them up. 

The next step, PRIME, began in November 1964 when the Space 

Systems Division of the Air Force Systems Command gave the Martin 

Company a contract to design, fabricate, and test a maneuvering reentry 

vehicle to demonstrate whether a lifting body could, in fact, be guided 

from a straight course and returned back to that course. Martin already 

had been studying lifting reentry vehicles for some time-the company 

had, after all, been in the Dyna-Soar competition-and had put more 

than 2 million man-hours into lifting entry studies. The outcome had 

been the SV-5 body shape, which resembled a finned potato. Company 

engineers built a 1.5-meter radio-controlled model and flew it at Martin’s 

Middle River, Maryland, plant. They raised it to altitude under two 

balloons, then dropped it and guided it to a landing. These quick-anddirty trials proved the shape could fly; eventually Martin refined the 

design into the SV-5D, a 400-kilogram aluminum vehicle with an 

ablative heat shield. The Air Force ordered four of the SV-5D PRIME 

vehicles, designating them X-23A and launching three of them between 

December 1966 and mid-April 196’7 over the Western Test Range using 

Atlas boosters that blasted them at 24 000 kilometers per hour toward 

Kwajalein. The three vehicles performed so well that the Air Force 

canceled the last launch to save money. The PRIME project demonstrated that a maneuvering lifting body could indeed successfully alter its 

flight path upon reentry. 

The Air Force and Martin had further expanded upon the company’s 

PRIME work and had derived PILOT-a proposed mach 2 “low-speed” 

research vehicle that the service could test to determine its supersonic, 

transonic, and subsonic-to-landing behavior. This vehicle the company 

designated SV-5P.15 

Martin also proposed a low-speed lifting body trainer, the SV-5J, to 

be powered by a small turbojet, for use at the Air Force test pilot school. 

Nothing came of this, though the company built the shells of two such 

vehicles and tried to entice a NASA pilot-one of FRC’s best-to fly it if 

and when it was completed.* On the other hand, the SV-5P development program went smoothly. The Air Force awarded Martin a contract 

*The pilot in question would have had to make three landings to earn a very lucrative payoff. 

The SV-5J would be very underpowered-perhaps too underpowered to gain enough altitude to 

execute the critical flare before landing. During consultations, colleagues waggishly proposed 

putting three logs across the Edwards runway. The SV-5J would hit the first, bounce, and the pilot 

would key his mike, calling “That’s one.” Bouncing over log 2: “That’s two,” followed by log 3: 

“That’s three,” followed by “Where’s my money?” Fortunately, for the sake of FRC‘s reputation and 

the health of the pilot, the SV-5J program died. 

156 
c I 

THE LIFTING BODIES 

for one SV-5P vehicle in May 1966, and the company began development under the direction of engineers Buz Hello and Lyman Josephs. 

Martin completed it a little over a year later, rolling it out of the 

Baltimore plant on 11 July 1967. The Air Force designated the craft 

X-%€A. It soon journeyed to Ames for comprehensive wind tunnel 

testing, and from there to Edwards, where the other lifting bodies, the 

M2-F2 and HL- 10, had already flown.16 

THE “HEAVYWEIGHTS” FLY 

Without a doubt, the lifting bodies were the ugliest of the postwar 

research aircraft. Only two were passingly handsome: the HL- 10 was 

pleasingly plump and the X-24B, with its laundry-iron shape, had 

rakish lines that hid the tubby bulge of its X-24A ancestry. Despite their 

lines, they generally flew satisfactorily. “Lifting bodies,” one test pilot 

remarked at the unveiling of the X-24A, “fly a lot better than they look.” 

For convenience, the aircraft will be discussed in the following order: the 

M2-F2 and M2-F3, the HL-10, and the X-24A and X-24B. 

The M2-FZ rolled out of Northrop’s Hawthorne, California, plant 

on 15 June 1965 and was trucked over the hills to Edwards the next day. 

It resembled the earlier M2-F1. At its unveiling, it still lacked the 

planned XLR- 1 1 rocket engine; NASA would fly it first as a glider and 

then modify it for powered flight. Fabricated from aluminum, the 

M2 - F2 weighed 2 100 kilograms and measured 6.76 meters in length, 

with a span of 2.92 meters. Like the earlier M2-F1, it had two vertical 

fins, but lacked the earlier craft’s horizontal control surfaces. Unlike the 

M2-F1, it had a retractable landing gear, assembled from off-the-shelf 

components, including the main landing gear of a Northrop T-38 

trainer and the nose gear of a North American T-39 Sabreliner. 

High-pressure nitrogen would blow down the gear just prior to touchdown. 

It had a complex series of body flaps: a full-span ventral flap controlled 

pitch, while split dorsal flaps controlled roll (lateral) motion through 

differential operation and pitch and trim through symmetrical operation. 

The twin vertical fins provided directional (yaw) control and also acted as 

speed brakes. The M2-F2 had a stability augmentation system to assist 

the boosted control system in damping out undesirable vehicle motions. The 

pilot could use four throttleable hydrogen peroxide rockets rated at 1780 

newtons (400 lb) apiece for “instant lift’’ during the prelanding flare; 

if the craft proved unmanageable or some other calamity struck, the 

M2-F2 had a modified zero-zero ejection seat from an F- 106 Delta Dart. 

At FRC, technicians checked out the aircraft, added research 

instrumentation, and then trucked it to Ames for two weeks of tests in the 

full-scale wind tunnel. Ames completed 100 hours of testing in August 

157 
ON THE FRONTIER 

1965; apart from a correctable high-frequency oscillation of the upper 

surface flaps, the M2-F2 received a clean bill of health. It returned to 

Edwards for its initial flight trials. Northrop furnished a special 6.7-meter 

adapter so that the M2-F2 could launch from the B-52 mothership’s 

existing X- 15 launch pylon. On 23 March 1966 the M2-F2 completed 

its maiden captive flight. Following a series of similar checkouts, NASA 

readied the craft for free flight.” 

In preparation for the MZ-FZ’s first flights, FRC launched a 

cooperative pilot training and aircraft simulation program with the 

Cornell Aeronautical Laboratory of Buffalo, New Ymk. Earlier, FRC had 

flown Cornell’s highly modified variable-stability Lockheed T-33A jet 

trainer to simulate the low lift-to-drag reentry characteristics of the 

X-15. Now, in the spring and summer of 1965, the FRC again flew 

Cornell’s T-33AY this time on lifting body studies, using the M2-F2 as 

the reference type. The variable-stability T-33A-in its own right, one 

of America’s most successful postwar research aircraft-had “drag petals” 

installed on its wingtip tanks. These petal-shaped surfaces, extended in 

flight, varied the lift-to-drag ratio of the aircraft from the T-33A’s 

normal 12 - 14 to as low as 2, the approximate ratio of an M2 lifting body. 

Typical lifting body approaches were executed by Cornel1 test pilot 

Robert Harper and by FRC pilots Milt Thompson, Bruce Peterson, Bill 

Dana, and Fred Haise. The T-33A tests indicated that the M2-F2 

aircraft would have undesirable lateral control characteristics under 

certain conditions-a fact that later assumed critical importance. In 

addition, NASA’s pilots simulated lifting body approaches and landings 

using the center’s F- 104s and the amenable Douglas F5D.18 

The M2-F2 completed its maiden flight on 12 July 1966. NASA 

pilot Milt Thompson dropped away from the B-52 mothership at 

13 700 meters, flying at ’725 kilometers per hour. During the brief 

flight-not quite four minutes-Thompson made a 90” turning descent, 

performed a practice landing flare maneuver at 7500 meters, made 

another 90” turn onto final approach, increased his gliding speed to 560 

kilometers per hour, initiated the landing flare at 365 meters reducing 

his rate of descent from 75 metedsecond to 3 meterdsecond, lowered 

the landing gear, and touched down exactly at the planned aiming point 

on Rogers Lake at 320 kilometers per hour, coasting 2.4 kilometers 

across the lakebed. The MZ-FZ’s first flight had been an unqualified 

success. By mid-November 1966 the craft had completed an additional 

13 flights, piloted by Thompson, Bruce Peterson, and the Air Force’s 

Capt. Jerauld Gentry and Lt. Col. Donald Sorlie. Following flight 14 on 

2 1 November, NASA grounded the M2 - F2 for installation of its XLR- 1 1 

rocket engine. On 2 May 196’7 the M2-F2 made its first flight carrying, 

but not using, the rocket engine, another glide flight piloted by Jerauld 

Gentry. Along with all other pilots who had flown the craft, Gentry did 

158 
THE LIFTING BODIES 

not like the M2 - F2’s poor lateral-directional stability characteristics. At 

low angles of attack at high speeds, it often developed a rolling motion 

that increased in severity. If the pilot increased the angle of attack, this 

motion damped out. On the very next flight this behavior contributed to 

a major accident that set back the entire lifting body program and 

seriously injured NASA’s Bruce Peter~on.’~ 

On 10 May 1967 Peterson launched away from the B-52 at 13 560 

meters, heading to the north and flying east of Rogers Dry Lake. All went 

well as the M2-F2 sank like a stone, until the wingless craft reached 2 135 

meters. Then, flying with a “very low” angle of attack, the M2-FZ began 

a “dutch roll” motion, rolling from side to side at over 200” per second. 

Peterson, who earlier had turned a nearly uncontrollable first flight in 

the HL- 10 into a brilliantly successful landing, was an excellent pilot; he 

quickly and instinctively raised the nose, damping out the lateral motions. 

The recovery had carried the craft away from its intended flight path. 

The pilot realized he was too low to reach the planned landing site near 

lakebed Runway 18 and was rapidly sinking toward a section of lakebed 

that lacked visual runway reference markings, which were needed to 

estimate height above the lake with accuracy. 

At this point, a rescue helicopter appeared in front of the M2-F2. 

Peterson, overburdened, disoriented from the rolling motions, now had 

an additional worry. He called, “Get that chopper out of the way,” 

following this seconds later with “That chopper’s going to get me, I’m 

afraid.” FRC chase pilot John Manke, flying an F5D, assured Peterson 

the helicopter was clear, and it did chug off, out of Peterson’s path. 

Realizing he was very low, Peterson fired the landing rockets, and the 

M2-F2 flared nicely. He lowered the landing gear, which needed only 1 ‘/2 

seconds to deploy from up-and-locked to down-and-locked. But time had 

run out. Before the gear locked, the M2-F2 hit the lake, shearing off its 

telemetry antennas. In the control room, engineers saw the needles on 

their instrumentation meters flick to their null points. Startled, they 

looked up to the video monitor-in time to see the M2-F2, as if in a 

horrible nightmare, rolling over and over across the lakebed at more 

than 400 kilometers per hour. It turned over six times before coming to 

rest on its flat back, minus its canopy, main gear, and right vertical fin. 

Peterson, who by all expectations should have died in the accident, was 

badly injured. Rescue crews pulled him from the wreckage, rushed him 

to the Edwards hospital for emergency surgery, then to the hospital at 

March Air Force Base, and several days later to UCLA’s University 

Hospital. He pulled through, though losing the sight of one eye. The 

plucky airman remained at the FRC as the center’s director of safety and 

continued to fly as a Marine reservist.“ 

Instead of simply trucking the M2-F2’s remains to a scrapyard, 

NASA returned them to Northrop’s Hawthorne plant. Technicians 

159 
0 

ON THE FRONTIER 

placed the battered lifting body in a jig to check alignment, removing the 

external skin and portions of the secondary structure. The inspection 

took 60 days. In March 1968 NASA’s Office of Advanced Research and 

Technology authorized Northrop to restore the primary structure and 

return the vehicle to FRC. There it sat, while lifting body advocates from 

Ames and FRC determined its future. In light of its poor handling 

characteristics, the craft obviously needed modification. By this time the 

rival HL- 10 was already demonstrating superior handling qualities. 

Nevertheless the M2 shape still appeared worth studying; on 28 January 

1969 NASA Headquarters announced that the agency would repair, 

modify, and return the MZ-FZ to service as the M2-F3.21 

The rebuilt aircraft, which returned to Edwards and first flew in 

1970, looked much like its predecessor, except for a short stubby vertical 

fin located midway between the two large vertical fins. This center fin 

acted as a large “flow fence” to improve lateral control. The craft had a 

new jet-reaction roll-control system, which NASA hoped might be used 

on future lifting body spacecraft so that the pilot could rely on a single 

control system all the way from orbit to landing, rather than the 

multiplicity of systems used on such craft as the X-15. NASA planned to 

employ the M2-F3 as a testbed for research on the lateral control 

problems encountered by lifting body vehicles. 

On 2 June 1970 Bill Dana completed the craft’s first flight, a glide 

flight to evaluate how the modifications changed the plane’s performance from that of the earlier M2-F2. A planned powered flight on 25 

November went awry when the engine shut down prematurely. Air Force 

test pilot Jerauld Gentry, the only pilot at Edwards to fly the MZ-FZ, 

HL- 10, and M2-F3, flew the plane on 9 February 1971 and said it flew 

as well as the HL-10; this was praise, for the HL-10 flew much better 

than the unmodified M2-F2. NASA and the Air Force then embarked on 

a joint program of incrementally increasing its speed and altitude 

performance, with the last two flights setting the fastest and highest 

MZ-FZ marks. On 25 August 1971 Bill Dana had made the craft’s first 

supersonic flight, attaining mach 1.1. Over a year later, on 13 December 

1972, Dana attained mach 1.613, 1712 kilometers per hour, the fastest 

M2-F3 flight. On the last flight of the craft, on 20 December FRC test 

pilot John Manke attained 21 790 meters, an M2 record. On only one 

occasion did trouble occur; on its tenth flight, 24 September 1971, the 

M2-F3 experienced an engine ignition malfunction; Dana shut down 

the XLR-11 engine, but a small amount of propellant flared briefly in 

the engine bay before extinguishing itself. Dana made “a hard but 

otherwise uneventful landing” on Rosamond Dry Lake, the alternate 

emergency landing site to Rogers. Toward the end of the craft’s flying 

career, FRC technicians installed and evaluated a rate command augmentation control system, a kind of fly-by-wire system that used an analog 

160 
c 

THE LIFTING BODIES 

computer and a side-arm control stick in addition to the regular control 

stick. Altogether, the M2 completed 43 flights. 16 as the F2 and 27 as the 

F3. Retired at the end of December 1972, the lane subsequently joined 

NASA complemented the M2 - F2 and M2 - F3 trials with an extensive 

evaluation of the Northrop HL- 10. In contrast to the accident-marred 

M2 flight test program, HL-10 testing moved along quite smoothlyonce the aircraft had been modified after a very frightening first flight. 

The HL-10, product of Eugene Love’s work at Langley Research 

Center, was among the most successful of the lifting bodies; indeed, 

when the Space Shuttle began to take shape, the consensus among NASA 

engineers at the Flight Research Center was that it should look like the 

HL-IO. Unlike the M2, which had a cone-shaped underside, the HL-10 

had a flat bottom and a rounded top; it was, in effect, an inverted airfoil 

in cross-section, with a delta planform. It had three vertical fins, two of 

them angling outwards from the body, and a tall center fin. The flush 

canopy did not protrude above the body lines of the vehicle. Like the 

M2-F2, it measured 6.7 meters in length, but it was wider (4.6 meters) 

and higher (3.5 meters). It used many off-the-shelf components from the 

T-38, T-39, and F- 106, among others. The control system consisted of 

upper body surface and outer fin flaps for transonic and supersonic trim, 

blunt trailing edge elevons, and a split rudder on the center vertical fin. It 

had a three-axis stability augmentation system, landing rockets, and 

provisions for an XLR- 11 engine, though the engine was not installed at 

roll-out from Northrop’s Hawthorne plant 18 January 1966.23 

Northrop shipped the vehicle to Ames for testing in the 40 X 80 ft 

full-scale tunnel. The tunnel tests proceeded uneventfully, though some 

tests hinted at flow separation over the outer vertical fins, a condition 

engineers did not consider serious. At the Flight Research Center on 22 

December 1966 NASA pilot Bruce Peterson completed the craft’s first 

glide flight. It was anything but routine. During the 3-minute descent to 

landing, Peterson discovered that he had minimal lateral control over the 

lifting body; flow separation was much worse than anticipated. Peterson 

managed to set the HL- 10 down safely on Rogers Dry Lake, no small 

tribute to his piloting skills. NASA immediately grounded it for study, 

also taking the opportunity to install its rocket engine. The first flight, in 

the words of Langley engineers, “once again demonstrated the value of 

flight tests as proof-of-~oncept.”~~ Langley undertook a series of tunnel 

tests. As a fix, NASA engineers modified the leading edge of the outer 

vertical fins so as to direct more air over the control surfaces. Technicians 

added the new leading edges, constructed of fiberglass, late in 1967, 

smoothing over the installation with epoxy paint. The HL- 10 experience reemphasized to engineers that aerodynamically shaping lifting 

body designs for good subsonic performance could lead to potentially 

161 

the collection of the Smithsonian Institution. 28 
ON THE FRONTIER 

disastrous flow separation problems in the absence of thorough design 

analysis. “This experience,” Langley engineers concluded, “. . . pointed 

up the significance of seemingly minor shape changes. . . .’’25 

When the HL-10 took to the air again on 23 October 1968, it 

handled very nicely. What was to have been the first HL-10 powered 

flight had to be aborted after launch when only one of the XLR-11’s 

chambers fired; Jerauld Gentry made an emergency landing on Rosamond 

Dry Lake. On 13 November everything clicked; NASA pilot John Manke 

reached mach 0.84 (843 kilometers per hour) using two of the engine’s 

four thrust chambers. NASA now began incrementally working toward 

the craft’s maximum performance. The HL- 10 went supersonic for the 

first time on 9 May 1969; this was the first supersonic flight of any 

manned lifting body and a major milestone in the entire lifting body 

program. The craft exhibited acceptable transonic and supersonic handling characteristics. On 18 February 1970 Air Force test pilot Maj. Peter 

C. Hoag reached mach 1.86 (2072 kilometers per hour), the fastest lifting 

body flight ever made; nine days later, on 27 February 1970, Bill Dana 

reached an.altitude of 27 524 meters, another record for the lifting body 

program. The HL- 10 thus became the fastest and highest-flying piloted 

lifting body ever built.26 

Toward the end of the HL-10 flight test program, NASA embarked on a series of powered landing trials. By 1970, the Space Shuttle 

was being discussed. One critical question was whether it should make 

unpowered landing approaches or, like a conventional transport aircraft, 

fly a powered approach and landing. Engineers had several schemes for 

the powered landing, the most popular being “pop-out” retractable 

turbojet “landing engines” that the Shuttle crew could deploy at subsonic 

speeds while approaching the earth. Advocates thought the landing 

engines would give Shuttle a shallower descent angle, reducing pilot 

workload and enhancing overall mission safety. While popular with many 

industry and government engineers who had little background in the 

“Round One,” “Round TWO,” and lifting body programs, this scheme was 

not at all popular at Edwards. Test pilots and engineers alike recognized 

the complexity that landing engines would add to any Shuttle design, as 

well as the danger to a Shuttle crew if one of the engines failed during the 

final and most critical portions of flight. Because of the popularity of this 

idea elsewhere, FRC engineers embarked on a powered-landing program using the HL-10. 

In February 1970, following the record altitude and speed flights, 

NASA grounded the HL- 10 and replaced its XLR- 11 rocket engine 

with three 2200-newton (500-lb-thrust) Bell Aerosystems hydrogenperoxide rocket engines. NASA planned launching from the B-52 in 

the vicinity of Palmdale; the pilot of the HL- 10 would ignite the rocket 

162 
THE LIFTING BODIES 

engines as the lifting body passed through an altitude of 2000 meters. 

The rockets would reduce the approach angle of the aircraft from its 

customary 18” to 6” and give the HL-10 an airspeed in excess of 560 

kilometers per hour. At 60 meters above the lakebed, the pilot would 

shut down the rockets and extended the landing gear, executin a 

routine landing. The HL-10 completed two of these flights pilotedgby 

Pete Hoag on 11 June and 17 July 1970, the latter flight being the craft’s 

final mission. The flights gave much more encouragement to the Edwards 

viewpoint than to those in favor of landing engines. The shallow descent 

angle had in fact increased pilot workload and degraded mission safety. 

Hoag found he had more trouble in determining the landing aiming 

point, and the higher approach speed aggravated control-sensitivity 

problems. 

The HL-10 tests carried the day for advocates of a “deadstick” 

Shuttle reentry, approach, and landing. As Milton Thompson, a test pilot 

with experience in numerous low WD research aircraft, subsequently 

stated, 

the shuttle, whether it has landing engines or not, must be maneuvered, 

unpowered, to a point near the destination because the engines cannot be 

started until the vehicle is subsonic and only limited fuel will be available. To 

us it seems ridiculous to maneuver to a position where power must be relied 

upon to reach the runway. 

The HL- 10, in large measure, contributed to the decision to design the 

Space Shuttle without landing engines.*’ 

During its brief flying career, the HL-10 completed 3’7 flights. In 

storage at the Dryden Flight Research Center, it awaits restoration and 

exhibition at the center, like its earlier compatriot, the X-1E. It was a 

fine flying vehicle, and its flight test program encouraged Eugene Love 

of Langley to advocate the HL- 10 design concept for any future NASA 

shuttle. For a variety of reasons, this did not come to pass. Pilots who flew 

the craft uniformly praised its handling ChaTacteristics, reserving criticism only for its bubble Plexiglas nose. The lenticular-shaped nose acted as 

a giant “demagnifying” lens at low altitude, causing severe visual 

distortion and misleading pilots into thinking that they were much higher 

over the lakebed than they really were. Consequently they sometimes 

waited too long before extending the landing gear. With experience, 

however, they learned to compensate for this distortion, and the problem 

disappeared. 

At first, NASA had no role to play in the Air Force’s X-24A 

(SV-5P) program. In mid-1965, before the Air Force had issued Martin 

a development contract for the vehicle (then designated SV-5P), NASA’s 

Ray Bisplinghoff and his opposite number in the Air Force, Alexander 

163 
a tv * 

ON THE FRONTIER 

Flax, had agreed in principle that the SV-5P should be added to the Air 

Force-NASAjoint M2-F2 and HL- 10 programs. OART was receptive 

to testing the SV- 5P, but the then-uncertain state of the program 

prevented inclusion of the SV-5P into the joint program until October 

1967, when NASA and the Air Force concluded a memo of understanding on use of the vehicle, now designated the X-24A. The memo also 

confirmed the earlier joint lifting body program agreements established 

by Paul Bikle and Maj, Gen. Irving Branch. Branch subsequently died in 

the crash of a T-38 trainer, but his successors at AFFTC had also 

approved participation in the NASA M2 and HL- 10 programs.28 

Martin had completed the X-24A at its Middle River, Maryland, 

plant in the summer of 1967. The craft had little aesthetic appeal; 

indeed, it could lay claim to being the most unattractive of these odd 

designs. Its ultimate maturation into the sleek X-24B shape thus has 

elements of the story of the ugly duckling that one day turned into a 

swan. The body shape differed greatly from the M2 and HL-10. 

Whereas M2 was basically a modified, boat-tailed half cone, and the 

HL- 10 a delta derivative with negative camber (Le., an inverted airfoil) 

and boat-tailing, the plump X-24A had positive camber. It had a 

landing weight of 2850 kilograms, a span of 4.1 meters, and a length of 

7.5 meters. After rollout on 11 July 1967, Martin shipped the craft to 

Ames for full-scale tunnel testing. That completed, NASA shipped the 

craft to Edwards in early 1969 for flight trials. Jerauld Gentry completed . 

the maiden glide flight on 17 April, the craft making nine more such 

flights before its first powered mission. Gentry flew the X-24A’s first 

powered flight on 19 March 1970, reaching mach 0.87, well into the 

transonic region. Following this flight, Gentry, NASA pilot John Manke, 

and Air Force test pilot Maj. Cecil Powell steadily opened the X-24A’s 

performance envelope. On 14 October 1970, 23 years to the day since 

Chuck Yeager’s first supersonic flight, Manke piloted the X-24A on its 

own initial excursion past mach 1, reaching mach 1.19 (1261 kilometers 

per hour) at 20 700 meters. Not quite two weeks later, Manke flew the 

X-24A to 21 765 meters, simulating a Space Shuttle approach and 

landing from that altitude. On 29 March 197 1 Manke reached mach 1.60 

(1667 kilometers per hour), the X-24A’s fastest research flight. On 4 

June 1971 the 28th and final research mission was a disappointment 

because only two of the XLR-11 engine’s four chambers ignited, 

limiting the craft to subsonic speeds2’ 

The little X-24A had no vices, though it once gave researchers a 

bad moment. The rocket engine shut down prematurely and a small fire 

erupted in the engine bay, but Gentry made an emergency landing. 

Damage to the four maneuvering flaps, wiring, and flap instrumentation 

kept the ugly duckling grounded for nearly two months. The X-24A did 

have one bothersome quirk: during boost, it exhibited a pronounced 

164 
a 

THE LIFTING BODIES 

nose-up trim change that prohibited low angles of attack during powered 

flight. FRC engineers concluded that the aerodynamic effects of the 

rocket exhaust plume impinging on the craft caused the nose-up condition, 

and warned the designers of the Shuttle to beware similar problems in 

that ambitious project. Though such trim changes sound innocuous, they 

could impose unacceptable aerodynamic loads on the Shuttle during its 

boost to orbit. Aside from this quirk, the X-24A flew very well and the 

pilots liked it. Like the M2-F3 and HL-10, the X-24A demonstrated 

that shuttle-type hypersonic vehicles could make precise landings without 

power. The X-24A pilots found they could land the vehicle on lakebed 

Runway 18 with an average 76-meter longitudinal “miss” distance from 

the intended touchdown spot. Indeed, NASA lifting body team members 

had no qualms about attempting landings on a confined concrete 

runway, such as the 4600-meter runway at Edwards. This had not been 

attempted with earlier lifting bodies only because they lacked nosewheel 

steering. All the lifting body trials gave great confidence to advocates of 

landing an unpowered Space Shuttle on a conventional runway after its 

return from space. This was the plan ultimately followed for the Space 

Shuttle and demonstrated at Edwards with the Orbiter Enterprise in 

1977.30 Had this been all that the X-24A contributed, the program 

would have been satisfactory. Instead, however, the ugly duckling turned 

into the sleek and significant X-24B. 

THE END OF AN ERA 

The Martin X-24B was America’s last postwar rocket research 

aircraft; its story began in the late 1960s when engineers at the Air 

Force’s Flight Dynamics Laboratory evolved a family of reentry shapes, 

the FDL-5,6, and 7, having a reasonable lift-to-drag ratio (approximately 

2.5) at hypersonic speeds and large internal volume. These configurations were all suited to hypersonic aircraft capable of flight from mach 4 

to orbital velocities, but tailored primarily for aircraft in the mach 8- 12 

performance regime. The Air Force hoped that these shapes could be 

used for two applications: sustained hypersonic-cruise aircraft powered 

by advanced airbreathing engines, and unpowered orbital reentry vehicles capable of landing at virtually any convenient airfield. At first, of 

course, the Flight Dynamics Laboratorywished to verify the performance 

of the shapes on low-speed lifting body vehicles. (See the color photo 

section at the end of this chapter.) 

In a bid to reduce costs, Air Force engineers thought of modifying 

one of the abortive Martin SV-5J shells into an FDL-7 body shape, 

gloving the FDL-7 around the SV-5J, retaining the three vertical fins, 

and redesignating this composite shape the FDL-8. In January 1969 the 

Flight Dynamics Laboratory issued a proposed development plan for the 

165 
a 

ON THE FRONTIER 

project, the jet-powered craft to be air-launched from a B-52 mothership. 

As studies matured, however, the advantages of rocket propulsion 

became obvious. This led the Air Force to scrap the SV-5J plan and, 

instead, build the FDL-7 shape around the X-24A then flying at 

Edwards. Because of the joint lifting body agreements, Air Force engineers had consulted their NASA counterparts, including Paul Bikle at 

the FRC and Fred J. DeMeritte, NASA OART’s chief of the lifting body 

program, to secure tentative NASA support. In August 1970, the 

laboratory sent a memorandum describing the proposed program to all 

interested parties. By the end of the month, the directors of both the Air 

Force Flight Test Center and NASA’s FRC had concurred, but Air Force 

Systems Command delayed approval pending arrangements for joint 

NASA-Air Force funding. On 11 March 1971 NASA transferred $550 000 

to the Air Force to initiate acquisition of the aircraft. The Air Force 

pledged a similar amount, and on 2 1 April 197 1 the AFSC’s director of laboratories gave the program its go-ahead, five months later than supporters 

had desired. On 4 June 1971 the X-24A completed its last flight. On 1 

January 19’72 the Air Force awarded the Martin Marietta Corporation 

the modification contract. The X-24B program was now officially under 

way, and modifying the existing craft secured for $1.1 million a research 

vehicle that could have cost $5 million if built from scratch. Hypersonic 

tests at the Air Force’s Arnold Engineering Development Center indicated that the FDL-8 shape performed well at those speeds. However, as 

always, the big question was what happened when the vehicle decelerated 

to much lower velocities. As Fred DeMeritte stated at the beginning of 

the program, “We are looking for surprises as we go through tran~onic.”~~ 

Martin Marietta Corporation’s Denver plant delivered the X-24B in 

the fall of 19’72. It had grown 3 meters in span and 4.4 meters in length 

and weighed 6250 kilograms at launch. It had a ’78” “double delta” 

planform for good center-of-gravity control, a boat-tail for favorable 

subsonic lift-to-drag characteristics, a flat bottom, and a sloping 3” nose 

ramp for hypersonic trim. Like the earlier lifting bodies, the X-24B 

used several off-the-shelf components; portions of its landing gear, 

control system, and ejection system came from the Northrop T-38, 

Lockheed F- 104, Martin B-57, Grumman F1 lF, Convair F- 106, and 

the North American X- 15. It had an XLR- 11 rocket engine and Bell 

Aerosystem landing rockets. Once the aircraft was back at Edwayds, 

technicians installed a research instrumentation package. Program managers Johnn Armstrong and Jack Kolf supervised preparations for the 

John Manke completed the X-24B’s first glide flight on 1 August 

1973, launching from the B-52 carrier aircraft at 12 200 meters, coasting 

earthward at 740 kilometers per hour, and performing a series of 

handling-qualities maneuvers and a practice landing approach before 

166 

first flight. 32 
THE LIFTING BODIES 

making a 320-kilometers-per-hour landing on the lakebed. The flight 

initiated the usual sort of programs and investigations that accompany all 

new research aircraft. On succeeding missions, Manke and the Air Force 

project pilot, Maj. Michael V. Love, checked the vehicle’s behavior in a 

variety of configurations. Following this series of glide flights the X-24B 

made its first powered flight piloted by John Manke, on 15 November 

1973. As always, the pilots practiced for their brief seven-minute sojourns 

in the X-24B with numerous lifting body simulation approaches in 

T-38 and F- 104 aircraft. By the end of the X-24B program, pilots had 

flown more than 8000 such approaches in support of the entire lifting 

body program. On the X-24B’s sixteenth flight, on 24 October 19’74, 

Mike Love reached mach 1.76 (1873 kilometers per hour), the craft’s 

fastest flight. Manke followed this on 22 May 1975 by making the craft’s 

highest approach and landing, coming down to the lake from a height of 

29 500 meters. Both Love and Manke were pleasantly surprised by the 

handling qualities at all speed ranges, and with and without engaging the 

control dampers in the stability augmentation system. Even in turbulence 

the aircraft flew surprisingly well; its handling qualities, including the 

landing approach, reminded pilots of the F- 104. Its subsonic handling 

qualities in general earned the X-24B a rating of 2.5 on the NACAdeveloped Cooper-Har er ilot rating scale, a very high mark. In short, 

By mid-1975 the Space Shuttle was well into its design phase; mission 

planners were still interested in whether such unpowered low WD 

reentry shapes could demonstrate successful landings on the relatively 

confined geographical and heading constraints of a fixed runway. John 

Manke was convinced that the X-24B could execute such an approach 

and landing. He recommended that the lifting body-which, in contrast 

to its fellows, did have nosewheel steering-make a series of landings on 

the main 4500-meter concrete runway at Edwards, Runway 04/22. 

Manke, Love, and others considered such a demonstration important to 

developing the confidence to proceed with similar landings of the Space 

Shuttle itself. In January 1974 the X-24B Research Subcommittee 

approved the proposal. Manke and Love began a three-week farniliarization program flying F- 104 and T-38 approaches that simulated the 

X-24B’s characteristics. Manke alone shot over 100 such approaches. 

The payoff came on 5 August 1975, when Manke launched from the 

mothership B-52, ignited the XLR-11 engine, climbed to 18 300 

meters, and began his descent. Seven minutes after launch, Manke 

touched down precisely at the planned target mark 1500 meters along 

the Edwards runway. Afterward he said: “We now know that concrete 

runway landings are operationally feasible and that touchdown accuracies 

of 2500 feet can be expected. We learned that the concrete runway, with 

its distance markers and unique geographical features, provides addiit was a fine airplane. 2 

167 
L t 

ON THE FRONTIER 

tional ‘how goes it’ information not available on our current lakebed 

runways.” Two weeks after Manke’s first runway landing, Mike Love 

duplicated the feat. The runway landing program, a major accomplishment, 

brought the X-24B research program to a conclusion. The Air Force 

and NASA embarked on a series of pilot checkout flights.34 

On 9 September 1975 Bill Dana completed the X-24B’s last 

powered flight, a flight that also brought to an end the postwar American 

rocket research program. No more would the rumble of an igniting 

rocket engine echo along the lakebed. No more would the XLR-11 

power some exotic airframe. Old-timers who had worked in the early 

days with Chuck Yeager and Walt Williams on the XS- 1 recognized that 

a unique period had at last come to a close. Following Dana’s flight, as the 

X-24B sat inert on the ground, the four chase planes, two T-38s and 

two F- 104s, closed up in a tight diamond formation and dipped low in a 

noisy salute over the Flight Research Center. That night, center personnel reminisced until the wee hours at an “End of an Era’’ party at the 

Longhorn, outside Lancaster. Following Dana’s flight, the X- 24B completed a series of six pilot familiarization glide flights, by Air Force Capt. 

Francis R. Scobee and NASA’s Einar Enevoldson and Tom McMurtry. 

On 26 November 1975 the X-24B dropped from the sky for the last 

time, piloted on its 36th flight by McMurtry. The NASA flight report 

concluded laconically that “all objectives for this flight were attained.” 

Through the dedication ceremony the following spring renaming FRC as 

the Hugh L. Dryden Flight Research Center, the X-24B remained at 

Edwards, resplendent in blue and white. Then it departed for the Air 

Force Museum, where it is currently exhibited. The lifting body flight 

test program gave way to the next phase: Space Shuttle’s approach and 

landing tests. 

BEYOND THE X-24B? 

Of Flight Research Center’s space-related activities in the 1960s, 

among the most important and influential were the lifting body studies. 

Evidence exists that the Soviet Union has followed a similar course, 

air-launching a lifting body shape reminiscent of the X- 20 Dyna-Soar 

from a Tupolev Tu-95 mothership. The Flight Research Center’s work 

on the other space-related projects-such as the Project Mercury drogue 

chute, the Paresev, and the LLRV-LLTV-was important, but the lifting 

bodies received the center’s greatest attention. The fact that the lifting 

body per se did not dictate the Space Shuttle shape is no reflection on 

NASA’s work with these shapes; indeed, the FDL-8 shape used on the 

X- 24B is considered ideal for a hypersonic sustained-cruise aircraft. 

Other considerations dictated the Shuttle’s shape; these, together with 

new thermal protection systems, lessened the once-urgent need for pure 

168 
THE LIFTING BODIES 

blunt-body lifting reentry vehicles. Writing in 1968, lifting body advocate 

Clarence Syvertson stated: 

A technology so new and challenging cannot be rushed. . . . But I believe that 

later in this century we will come to regard today’s purely ballistic manned 

capsules, splashing down in an ocean, as a relatively crude and inefficient way 

of returning from a space mission. The lifting body offers an alternative that 

is already proved in prin~iple.’~ 

NASA’s lifting body program led to two abortive research efforts, a 

“mini-Shuttle” and an air-breathing hypersonic follow-on to the X- 24B. 

In the former case, center engineers proposed construction of manned, 

flying, 11-meter versions of the Space Shuttle to study the most critical 

area of its flight, the deceleration from mach 5 through the landing. 

Mach 1, 2, and 3 models were to be powered (respectively) by one, two, 

and three XLR- 11 engines, or a mach 5 model could be powered by an 

XLR-99. Such research aircraft, air-launched from a B-52, could fly ‘in 

direct support of Space Shuttle development, especially by validating 

wind-tunnel predictions of stability, controllability, and performance at 

hypersonic, supersonic, transonic, and subsonic velocities. They could be 

used for astronaut training and for investigating launch abort maneuvers. 

As with the earlier lifting bodies, FRC advocates of the subscale shuttle 

planned on using components from a variety of existing aircraft, including the M2-F3, F-4, YF- 12, F- 15, and X- 15, as well as some Apollo 

hardware. It was hoped that, using this approach, costs could be kept 

down. An XLR-99-equipped mach 5 subscale shuttle was estimated to cost 

$19.7 million. If NASA’s Office of Aeronautics and Space Technologythe successor to OART-and the Office of Manned Space Flight had 

authorized immediate go-ahead, the mini-Shuttle could have been flying 

toward the end of 1975.36 

This was a typical Flight Research Center proposal: do something 

that no other center could do, and do it in support of a broader research 

program. Unfortunately, the proposal came to grief. The major push for 

a subscale shuttle came in August 1972, with preparation of a well 

defined and detailed proposal. Following this, Milton Thompson, Joe 

Weil, and other mini-Shuttle proponents traveled to the Manned Spacecraft Center and NASA Headquarters to make presentations for the 

vehicle. It had some high-level support-Robert Gilruth of MSC was a 

strong advocate-but critics argued that the projected costs were far too 

low, that a realistic cost estimate would be more like $150 million. FRC 

supporters pointed to costs in the earlier FRC-managed lifting body 

program. They conceded that if the program went through conventional 

management procedures at Headquarters, its costs would indeed rise. 

Other critics believed FRC could not go it alone on the project and that it 

would ultimately involve people who were at work on the Shuttle. But the 

169 
c a 

ON THE FRONTIER 

overriding difficulty seems to have been a matter of pride: FRC justified 

the subscale shuttle on the basis of its validating and verifying the results 

of wind tunnel testing-an old sorespot to tunnel devotees who passionately believed in their facilities. Despite strong industry support from 

Northrop and Martin (both with lifting body experience) and Rockwell, 

the Shuttle contractor, the subscale shuttle succumbed to the cost 

argument. The actual Shuttle’s hypersonic, supersonic, and transonic 

performance remained unchecked by actual results until the first all-out 

mach 25 reentry from space.” No one seems to have proposed a subscale, 

unmanned shuttle reentry vehicle to be flown like the earlier ASSET and 

PRIME shapes. There is no reason to believe that such a proposal would 

have won a~ceptance.~’ 

The other proposal derived from the lifting body effort, as well as 

desires for an X-15 follow-on, was the “X-24C,” a strange aircraft 

subsequently awkwardly redesignated as the NHFRF: National Hypersonic 

Flight Research Facility, pronounced “Nerf.” The Flight Research Center 

had high hopes for development of this vehicle, a B-52 air-launched 

mach 8 research aircraft equipped with rocket boost and designed for 40 

seconds of sustained mach 6 + cruise. FRC, in conjunction with Langley’s 

hypersonic ramjet research program, could use the aircraft to test 

“Scramjet” (supersonic combustion ramjet) air-breathing engines. As early 

as the mid-l960s, De Beeler of the Flight Research Center had pressed 

hard for development of such a craft. With the conclusion of the X- 15 

program in 1968, calls from enthusiasts for an advanced hypersonic airbreathing research aircraft became clamorous. Langley Research Center 

launched two programs: HYFAC, the Hypersonic Research Facilities 

study, a mach 12 design; and the less ambitious HSRA, a mach 8 HighSpeed Research Aircraft. The Air Force originated two proposals, one 

for a mach 3-5 test vehicle, and the other for the Incremental Growth 

Vehicle, a test airplane initially designed for mach 4.5, but which could be 

modified for flight at mach 6, and later for mach 9. Starting in July 1974, 

after recognizing the probable high costs of the program, NASA and the Air 

Force jointly conducted a series of design studies for an air-breathing 

hypersonic vehicle. The Flight Dynamics Laboratory FDL- 8 body shape 

appeared ideal; studies pursued this approach, encouraged by Air Force 

research on two proposed follow-on X-24 configurations, one with 

“cheek” air inlets, and the other with an XLR-99 rocket engine. In 

December 1975 NASA Headquarters and the Air Force established an 

“X-246” Joint Steering Committee, composed of the commanders of 

the Air Force’s Flight Dynamics Laboratory and Flight Test Center, and 

*For the record, its behavior was highly satisfactory. 

170 
THE LIFTING BODIES 

the directors of NASA‘s Langley and Flight Research Centers. In July 

1976, out of this joint committee came the NHFRF.38 

The NHFRF came close to winning approval. It was strongly 

supported at Dryden at all levels. Langley’s hypersonic aerodynamicists 

and propulsion team saw in it the fruition of all their work. They also saw 

it as a good opportunity to “cover the whole hypersonics waterfront and 

do it before we’ve lost all the hypersonic talent we developed from the 

X- 15 program.” There were certainly psychological overtones as well, 

primarily a desire to reassert and revitalize the role of aeronautics within 

the agency. NASA forecast a $200-million program involving construction of two aircraft, with 200 flights over a 10-year period. The agency 

and the Air Force would start funding the program in 1980, with the first 

airplane flying in 1983. To Dryden management, uneasily eyeing the 

future of the center after the Space Shuttle left the lake for the last time, 

the NHFRF seemed especially important for the 1980s. It would be the 

logical conclusion of two decades of X- 15-X-20A-X-24B 

What happened was a sad anticlimax. Discussions between the Air 

Force and NASA continued into 1977. As plans grew, so did the expected 

cost of the vehicles. The 40-second cruise requirement added complexity 

that translated directly into higher costs. Finally, despite the wishes of 

NHFRF supporters at Edwards and Langley, NASA Headquarters 

canceled the program in September 1977. James J. Kramer, NASA’s 

acting associate administrator for aeronautics and space technology, 

stated that “the combination of a tight budget and the inability to identify 

a pressing near-term need for the flight facility had led to a decision by 

NASA not to proceed to a flight test vehicle at this time.”40 The Air Force 

was in no financial or political position to go it alone on such an ambitious 

venture. The result hit Dryden hard. Center morale dropped precipitously. 

Some blamed over-management. Some blamed the cruise requirement. 

Others felt the FRC should have pressed harder for a no-frills off-theshelf shape. It was all to no avail: NHFRF was gone. 

It is ironic that the center’s work with lifting bodies for reentry from 

space eventually spawned an abortive interest in hypersonic atmospheric 

flight. It was a joining together of two streams of research: the stream 

running from the X- 15 through the X-20 and on to the HSRA; and the 

stream running from the Allen blunt body to the Eggers M2, the Love 

HL-10, the Martin SV-5, the FDL-8/X-24B, and the NASA HYFAC. 

Both streams pooled together in the NHFRF. The subscale shuttle was 

certainly spawned by the lifting body program, and constitutes a little 

puddle of its own to the side. It did not influence the work on what 

became NHFRF, though some of its technology was very close. Following 

the cancellation of the NHFRF, there was a general feeling among 

subscale-shuttle proponents that it might have evolved into a research 

17 1 

4 
ON THE FRONTIER 

tool, like the NHFRF, had NASA proceeded with development. That is 

indeed likely. 

With cancellation of the NHFRF, the national program on transonic, 

supersonic, and hypersonic flight research using specialized rocketpropelled research vehicles was over. The actual Space Shuttle, of course, 

does not fit in any of these research areas. As its enthusiasts claim, it is a 

space-age DC- 3, a vehicle to revolutionize manned and unmanned 

orbital spaceflight. The cancellation of NHFRF came in the midst of the 

center’s program on the Space Shuttle. The Shuttle was, for a very brief 

time, a major center program. While Johnson Space Center (formerly 

MSC) had overall control of the program, Dryden furnished the technical expertise on flight-testing to validate the craft’s approach and landing 

characteristics. The Shuttle program ultimately involved a great number 

of center personnel, plus others from Johnson, and brought Dryden its 

greatest public exposure. The odd sight of a 747 carrying and then 

launching a delta monstrosity the size of a DC-9 airliner could not help 

but draw attention. The Shuttle program involved a lot of preparation, 

including a special “mate-demate” facility, a microwave landing system, 

and work on the 747 mothership. Yet this transitory program was over 

almost as soon as begun and did not reappear until four years later, when 

the first Space Shuttle dropped out of the Mojave skies to land on the 

Edwards lakebed. 

The center’s involvement with space came as a prelude to the Space 

Shuttle. But the same years that witnessed the X-15, the Paresev, the 

LLRV, and the lifting bodies also saw a return to conventional aeronautics: 

flight at transonic and supersonic speeds. Though the Flight Research 

Center did not run an extensive number of service-type test programs in 

the 1960s and early 1970s, several aeronautical research projects were 

under way. Some of these, such as the Blackbird, XB-7OA, Supercritical 

Wing, and the TACT program, became quite visible and were very 

important, both in terms of their technology contributions and in how 

they promoted the reputation of the center. Though they played second 

fiddle during the heydey of space, it has been these programs-and 

others like them-that have since emerged as Dryden’s life blood. 

172 
In the foreground, lifting body configurations that were launched from “Mother,” the large 

twin-engine radio-controlled model airplane in the background. 

The plywood M2-Fl lifting body in towed flight over Rogers Dry Lake. 
The “heavyweight” Northrop M2 -F2 lifting body. 

Three lifting body vehicles line up on Rogers D~J Lake (left to right): the Martin X-24A, 

the Northrop M2-F3 (rebuilt from the M2-F2), and the Northrop HL-10. The M2 

and HL-10 were both NASA concepts. 

NASA’s A-SA, wed for simulation studies of the supersonic transport in 1963. 
The Martin X-24B, whose laundry-iron shape was added to the existing Martin X-24A, 

giving it a new lease on life. 

Seconds from touchdown, the Martin X-24B flares above Runway 18 on Rogers Dry 

Lake. The craft's shadow on the lake bed clearly delineates its slender delta configuration. 

The Flight Research Center's variable-stability North American F-1 OOC Super Sabre was 

used for a range of airborne simulation studies, including some in support of the X-15 

and SST programs. 

a 
A low sun angle highlights the blended wing-body configuration of NASA’s mach 3 4- 

YF -1 2C Blackbird. 

North American’s awesome XB - 70A Valkyrie thunders off the lake on a research mission. 

NASA flew this large supersonic aircraft in support of the national SST program. 
6 

9 

Mach 3 Again: 1966- 1979 

As long as NASA had not yet fulfilled its mandate of landing men on 

the moon before the end of the 1960s, aeronautics had to take a second 

place to space within the agency. Yet even before Neil Armstrong’s “one 

small step” at Tranquillity Base, a ground swell of renewed interest and 

support for aeronautics was building. Within the agency, engineersespecially those at the old NACA centers, Langley, Ames, Lewis, and 

Flight-decried the imbalance. In May 1966, a congressional report 

bluntly stated that “any new or expanded aeronautical activity within 

NASA immediately has to compete for attention, money, resources, and 

manpower with an urgent, presidentially declared, national space goal. 

Under these circumstances it is perhaps surprising that NASA’s aeronautical efforts have not suffered any more than they have.”’ And the 

Flight Research Center, so recently out of favor with some congressional 

staffers, now came back into the good graces of the legislative branch. 

Indeed, the same report credited the FRC with “a spectacular series of 

technological ‘firsts.’ ” 

Several major developments suggested the need for greater aeronautical research and development. First, a protracted war in Southeast Asia 

was revealing surprising problems with American aircraft and airpower 

doctrine. In one measure, the overwhelmingly favorable air-combat 

victory-loss ratios of earlier wars--8 to 1 against the Luflwufe and about 

12 to 1 against North Korea-were missing; indeed, at times the 

victory-loss ratio slightly favored the North Vietnamese. Advancing 

aircraft technology offered the hope that clear military air supremacy 

might be regained. Foreign military aircraft technology was moving 

rapidly, especially in the Soviet Union. NASA’s OART, in an in-house 

19’7 1 study, concluded that “the U.S. traditional preeminence in military 

airpower has been lost in recent years. While progress in foreign 

airpower during the last decade has been rapid, few truly advanced 

aircraft have been developed in this ~ountry.”~ Second, new generations 

of jet transports-particularly supersonic jet transports-were being 

177 
ON THE FRONTIER 

developed in the US., Europe, and the Soviet Union. NASA’s aeronautical partisans and congressional supporters recognized a need to strengthen 

America’s traditional position of leadership in civil air transportation. For 

the 1960s, this meant supporting the national SST effort. Further, 

vertical-takeoff-and-landing (VTOL) and short-takeoff-and-landing (STOL) 

aircraft, new advanced wing designs for more efficient transonic and 

supersonic flight, and new concepts for flight-control systems-all these 

would require sustained NASA research. 

NASA’s Langley Research Center remained, as it had always been, 

the agency’s principal aeronautical research resource. Langley was the 

agency’s “team leader” for advanced supersonic aircraft design, particularly in relation to the national SST program, then a joint effort between 

NASA, the Federal Aviation Administration, and American industry. 

When NASA began devoting more time and resources to aeronautics 

from the mid-1960s onward, Langley intensified its own research. The 

Flight Research Center followed these activities as much as possible, 

offering opinions and judgments as to what technical policies and 

programs NASA should support. The center remained heavily committed to the space-related efforts of the X- 15, LLRV, and lifting bodies, so 

the amount of engineering talent available to work on non-hypersonic 

non-space-oriented programs was relatively small. Nevertheless, the 

center applied some resources to comprehensive supersonic research in 

support of the national SST effort and, later, to research on improving 

the efficiency and performance of transonic aircraft. This involved the 

center in four major aeronautical research programs: the XB -70A, 

YF- 12, F-8 Supercritical Wing, and F- 11 1 Transonic Aircraft Technology effort. The first two involved research in sustained mach 2.5-3 + 

flight. The latter two were concerned with transonic aircraft design. 

Figure 4 places these four programs within the context of selected FRC 

activities from 1959 through 1980. The gradual deemphasis on space 

research in favor of more traditional aeronautical research is obvious, 

and FRC’s experience mirrors that of Langley, Ames, and Lewis over 

the same peri~d.~ 

EARLY SUPPORT OF THE SST 

FRC’s supersonic research during the 1960s emphasized support of 

the national SST program, a logical outgrowth of the center’s research on 

“Round One” and Century Series aircraft in the 1950s. The American 

SST program had begun in 1963, but dated to a Kennedy Administration 

initiative in 1961 that called for development of a mach 3 supersonic 

transport. With hindsight, the goal was obviously ill-chosen; the complexity of such a craft and its enormous costs made it at best luxury and at 

worst a severe burden on the airline community expected to buy it. 

178 
MACH 3 AGAIN 

HL-10 

M2-F3 

X-24A 

X-24B 

XB-70A 

YF-1% 

YF-12C 

’ F-8 SCW 

M2-F2 

F-111 TACT 

- 

- 

* - __-_- 

- 

- .I

- 

- 

- - 

- - 

- 

- 

- - t 

11l11111111 

- 

* 

t 

Grounded following first flight for additional R&D 

Ongoing program 

Figure 4. Selected Dryden Flight Research Center research programs, 1959-1 980, 

Proponents argued for an SST largely from a “pure” technology standpoint, 

with overtones of nationalism. The requisite technology base exists for 

such a craft, the argument went, as a result of the nation’s supersonic 

research program in the 1950s and the development of such supersonic 

bombers as the B-58 and the XB-70; therefore, the country should do 

it. Often added to this was the thought that if the United States did not 

develop an SST, Europe or the Soviet Union would sweep past American 

technology with their own SSTs. Thoughtful arguments questioning a 

mach 3 SST’s cost, utility, and desirability were ignored, especially after 

1963, when the Federal government had committed itself to supporting 

development of such a craft as a major American aeronautical research 

and development initiative. 

In 1963, the Flight Research Center was flying three military aircraft 

on SST studies. Because the Douglas F5D-1 Skylancer had a modified 

delta-wing planform similar to wing configurations suggested for a 

mach 3 SST, center pilots flew the F5D-1 on SST landing studies, 

179 
R 

ON THE FRONTIER 

accumulating data on sink rates and approach characteristics. A North 

American F- 1 OOC Super Sabre, modified to have the variable-stability 

characteristics that would simulate the handling qualities of an SST, was 

acquired from Ames and flown to generate information on predicted 

SST handling qualities. FRC also acquired a North American A-5A 

Vigilante attack bomber from the Naval Air Test Center at Patuxent 

River, Maryland, and flew it to determine the let-down and approach 

conditions of a SST flying into a dense air traffic network. During 1963, 

center pilots Milt Thompson and Bill Dana flew the Vigilante over 

remote areas around Edwards on expected supersonic transport flight 

profiles and even flew supersonic approaches into the terminal approach 

control zone to Los Angeles International Airp~rt.~ The A-5A was 

returned to the Navy at the end of the year. 

lanned to 

provide funds-and eventually did contribute approximately P 2 millionto instrument the experimental North American XB -70A Valkyrie 

mach 3 + bomber so that it could return supersonic-cruise research data. 

In February 1963, the center purchased a Lockheed Jetstar four-engine 

business jet; suitably instrumented with an analog computer, it could 

simulate the handling characteristics of a wide range of aircraft, including SSTs. FRC purchased the Jetstar for $1 325 000 and sent it to the 

Cornel1 Aeronautical Laboratory at Buffalo, New York, for installation of 

the simulation equipment at a cost of an additional $1.3 million. Back at 

Edwards for test duty in November 1965, it was known as the GPAS: 

general purpose airborne simulator. Many engineers believed that any 

SST would require a movable “droop” nose (such as later employed on 

Concorde) for adequate pilot visibility in the high angle of attack 

assumed by such an aircraft on takeoff and landing. Others believed 

visibility could be provided by an extendable, periscope-like, binocular 

system. FRC engineers installed binocular optics in the center’s two-seat 

F-l04B, and center pilot Bill Dana evaluated it in flight. The press of 

concurrent X- 15 work terminated the program; eventually, the advocates of the “droop nose” carried the day.5 By the middle 1960s, then, 

the FRC was definitely SST-minded in its aeronautical research. Its principal 

involvement with the,SST program came with the XB - 70A test program. 

(See the color photo section preceding this chapter.) 

FRC went beyond these efforts. The research staff 

THE XB-70A ACCIDENT 

North American’s XB -70A Valkyrie was a six-engine experimental 

bomber designed for mach 3 + speeds. Generally, the two prototypes of the 

XB - 70A closely resembled the aerodynamic configuration that could be 

expected of a large supersonic jet transport. At the time of its maiden 

flight on 21 September 1964, the Valkyrie was the world’s largest 

180 
MACH 3 AGAIN 

experimental airplane, with a length of 58 meters, a wingspan of 32 

meters, and a height of 10 meters. It had two large vertical fins, a canard 

(“tail-first”) horizontal control surface mounted on the fuselage, and a 

sharply swept delta wing, the tips of which could be lowered to furnish 

greater supersonic lateral (roll) and directional (yaw) stability. Constructed of titanium and brazed stainless steel “honeycomb” materials, it 

could withstand sustained temperatures on the order of 332°C as it 

cruised at high altitude and mach 3. It was designed as an intercontinental bomber, but production in quantity was canceled before its first flight 

because of changes in Defense Department offensive doctrine. Instead, 

the government decided to complete the two prototypes and use them 

for mach 3 research in support of the SST program. The first XB-70A 

had an FRC-funded package of test instrumentation capable of telemetering 36 separate measurements of aircraft performance and condition to 

ground stations. A further 900 measurements were recorded by digital 

pulse-code-modulation and analog frequency-modulation recording systems on magnetic tape at the rate of 20 000 samples per second-a far cry 

from the scratchy oscillograph film used on the old X- 1. 

During the first phase of its flight-test program, the XB-70A and its 

later sister ship were flown by North American and Air Force test pilots. 

The planes were routinely flying above mach 3 by early June 1966. Turns 

required flight corridors hundreds of kilometers wide; obviously an SST 

could not use conventional airway routes, a vital discovery. The first 

airplane proved to have poor stability characteristics above mach 2.5; on 

the basis of wind-tunnel studies at Ames, North American had added 5” 

dihedral to the wing of the second XB-70A. This airplane had much 

better stability characteristics above mach 2.5, so researchers designated 

it the prime mach 3 research airplane. The complex systems of the 

airplanes posed maintenance headaches. Also poor bonding of the 

stainless steel skin on the wing sometimes allowed whole sections of it to 

peel off in flight. Landing gear retraction problems plagued the craft; 

in one case, because of partial gear failure, the plane veered almost a 

kilometer off a lakebed runway’s centerline, causing the test pilot to 

scribble in his report, “This landing could not have been accomplished on 

any runway in this country. Thank God for Rogers Dry Lake. . . .,, Despite all these difficulties, the XB-70As were returning a great deal 

of useful information for SST designers-on noise, operational problems, 

control system requirements, validation of tunnel test techniques by 

comparison with actual flight-test data, and high-altitude clear-air 

turbulence.6 

NASA’s OART had already allocated $10 million for support of the 

XB-70A program, primarily for flight-test instrumentation on the first 

and second aircraft. Then in the spring of 1966, the Air Force and NASA 

announced a joint $50-million program to be run by FRC and the Air 

181 
ON THE FRONTIER 

Force Aeronautical Systems Division. To begin in mid-June 1966, at the 

conclusion of the North American airworthiness demonstration program, 

the joint NASA- Air Force program would study the problems of sonic 

booms and evaluate the aircraft during typical SST flight profiles. FRC's 

Joe Walker was designated project pilot for the civilian agency. 

On 8 June 1966, the second XB-70A took off from Edwards, 

piloted by North American test pilot A1 White and a new copilot, Maj. 

Carl Cross, making his first flight in the plane. The XB-70A was to 

make a series of tower passes at various airspeeds to calibrate its onboard 

airspeed system, then make a single pass at mach 1.4 and 9450 meters to 

acquire sonic boom information during an overflight of a specially 

instrumented test range. There was another item on the flight plan, not a 

critical one: the Air Force had approved a request by General Electric for 

the XB-70A to lead a formation of aircraft equipped with General 

Electric engines. The XB-70A used GE J93s. Participating would be a 

Navy F-4B Phantom, an Air Force T-38A Talon and YF-5A, and a 

NASA F-104N Starfighter piloted by Joe Walker. A Lear Jet would 

photograph the formation for publicity purposes. At the preflight 

briefing the day before, John Fritz, a GE test pilot who would be flying 

the YF-5A, advised the other pilots to fly a loose formation, with about 

one wingspan clearance between airplanes.' 

The XB-70A took off from Edwards at 7:15 a.m. on 8 June, 

followed by a T-38A piloted by Pete Hoag and Joe Cotton. White and 

Cross made three tower flybys, aborted a fourth because they were not 

properly aligned with the course, and canceled the remaining eight 

because of low altitude turbulence. At 7:59 White and Cross climbed for 

altitude while Hoag and Cotton landed and refueled their T-38. White 

and Cross completed the sonic boom pass by 8:30 and headed for the 

formation flight rendezvous point, Lake Isabella. By 8:43 the F-4B from 

Point Mugu, the YF-5A, the NASA F-l04N, the photo Lear Jet, and 

the now-refueled T-38 had all joined up with the big white delta. The 

plan for the formation flight called for the XB-70A to lead the other 

aircraft on a racetrack pattern between Mojave and Mt. Whitney at 6 100 

meters. White and Cross soon discovered that clouds precluded this 

original plan and changed to a racetrack pattern northeast of Rogers. 

The new track was much shorter: the formation covered the straight 

portion of the track in a little over a minute and then made a 3-minute 

turn through 180". The Air Force T-38 and Navy Phantom rode off 

the XB-70A's left wing, with Walker's Starfighter and the YF-5A on 

the right. A two-seat Air Force F-104D returning from a test mission 

briefly joined the group while the rear-seat cameraman took high-speed 

motion pictures, using up his film. The visiting pilot noticed that the two 

right-hand aircraft, the F- 104N and YF-5A, were flying a much tighter 

formation than the Navy F-4B and Air Force T-38. He suggested the 

182 
c 

MACH 3 AGAIN 

T-38 tighten its position relative to the F-4B to improve the looks of the 

formation.* 

The F- 104D left for Edwards while the. XB-70A flew along, 

followed by its flock. Joe Walker in the F- 104N edged closer and closer 

to the mammoth research airplane. A B-58 on a test flight passed high 

overhead. Then, for reasons that will forever remain unknown, Walker’s 

plane closed with the XB-70A7 its horizontal stabilizer touching the 

downturned tip of the Valkyrie’s wing. 

Why? There were a lot of possible factors. For one thing, Walker was 12 

meters ahead of the tail of his plane, a plane with an unusual protruding 

tail configuration, a T-tail that had its maximum width high above 

Walker’s cockpit. Then there was the long, sharply swept leading edge of 

the XB-70A’s wing: deltas are notoriously difficult to maintain formation on, and the chances for misjudging distance are high. Checking wing 

and tail clearances would have required Walker to resort to extreme neck 

craning. There was the possibility of pilot distraction: the group had held 

formation for 43 minutes, not unsafe or unusual for a loose formation, 

but dangerous for a tight one. Then there was the darting Lear Jet and 

the oncoming B-58. That initial F-104N motion was slight; even the 

YF-5A pilot, off Walker’s right wing, failed to detect a significant change 

in the Starfighter’s position. 

In any case, the F- 104N touched the XB-70A and then, passing 

through the leading edge vortex of the XB-70A’s wing, the Starfighter 

rapidly rolled over the top of the XB-70A7 hooking its left wing tank on 

the Valkyrie’s wing. The tip tank broke up, initiating a built-in sequence 

so that the F- 104N’s right tank immediately jettisoned. The Starfighter, 

still rolling over the XB-YOA, smashed into the right a‘nd left vertical 

fins, exploded in flames, and impacted the top of the XB-70A’s left 

wing. Walker was killed instantly. The F-104N fell away in bits of 

wreckage and flame; the XB-70A continued on, minus its vertical fins 

and with major damage to both wings, a doomed air~raft.~ 

The other aircraft reacted immediately. Hoag and Cotton radioed 

“Mid-air, mid-air!” followed by “You got the verticals, this is Cotton, you 

got the verticals-came off left and right. We’re stayin’ with ya, no sweat, 

now you’re holdin’ goodAl.. . .”The F-4B and YF-5A broke formation. 

The Lear Jet stayed away. The XB-70A continued to fly straight and 

level for 16 seconds. In the cockpit, White and Cross were unaware that 

they had been involved in a collision; White thought it might be two of 

the chase planes, and he missed the “s” on Cotton’s “verticals,” Then the 

XB-70A abruptly yawed right and rolled right, tumbling over and over 

so violently that White thought the plane’s nose would break off. Hoag 

and Cotton still called “Bailout, bailout, bailout” over and over. Finally a 

parachute appeared; one pilot was out. In fact, the chute belonged to White, 

who had just waged a successful struggle to stay alive. After he initiated 

183 
c x3 a 

ON THE FRONTIER 

the escape sequence, the capsule’s closing clamshell doors trapped his 

right elbow; he worked it free, but then the doors would not close, and he 

ejected in that condition. The doors had inflicted painful shoulder 

injuries, but White faced a more serious problem: the open doors 

prevented the capsule’s built-in “shock attenuation bag” from deploying. 

The capsule struck the ground with a 45-g force, causing White severe 

internal injuries. Carl Cross died in the wreckage of the Valkyrie. The 

copilot’s ejection capsule never even left the airplane.” 

One minute and 11 seconds after the collision, the XB-70A spun 

into the ground and exploded, six kilometers northwest of Barstow. 

Walker’s F- 104, in several pieces, was already burning in the desert, 16 

kilometers away. White’s capsule floated downward. Woag and Cotton 

circled around and around, looking for another chute. Back at Edwards, 

ground monitors received the first word of the accident. It spread like 

wildfire through the center, a numbing shock. A casual observer of flight 

testing might wonder why the participants are not hardened to death, but 

it is not so. One mathematician reflected: “You just feel so defeated. You 

know what I mean? The life you can’t replace. The loss of the aircraft was 

secondary. You can get another airplane, but you can’t get another pilot 

like that.” The word first came from Operations: an accident had 

occurred, an accident involving the XB-70A. Little knots of people came 

by. All Operations knew was that an F- 104 had hit the XB-7OA. Then 

came confirmation. NASA F- 104N 8 13 had collided with the XB - 70A. 

Both aircraft were down. Joe Walker was presumed dead, as was one of 

the XB-70A crewmen. Then came the final word: Walker and Cross 

dead, White badly injured, two airplanes destroyed. l1 

Of course, there was an accident investigation. The Air Force 

Directorate of Air Safety established a team of more than 60 people, and 

a smaller accident board as well. The board was under Air Force control, 

and NASA’s official representative, FRC engineer Donald Bellman, was 

a non-voting member. Wreckage analysis clearly indicated what had 

happened, and the XB-70A’s telemetry system had transmitted data all 

the way down to impact. The XB-70A program had great national 

visibility, and the deaths of Walker and Cross called forth tributes from 

many quarters. NASA Deputy Administrator Robert Seamins cited Joe 

Walker for his many contributions to flight research, and President 

Lyndon Johnson issued a statement of tribute from the White House.12 

Charges over the wisdom of risking the XB-70A and the lives of test 

pilots merely to provide corporate publicity photographs flew back and 

forth. But none of this could change the unhappy situation: two test 

pilots had died and two aircraft had been lost. NASA’s Flight Research 

Center had lost a valued colleague, and the XB-70A program had received a serious setback. 

. 

184 
MACH 3 AGAIN 

FRC’s XB-70A PROGRAM 

The accident to the second XB-70A drastically altered plans for 

NASA’s joint SST research program with the Air Force. After the first 

numbing shock, the FRC went back to work, assessing where the 

program now stood. The first XB-70A was down for maintenance, 

including modifications to its landing gear, instrumentation, and inlet 

system. It did not resume flying until November 1966. Meanwhile, the 

Air Force reassessed its own plans for the aircraft. The second XB-70A 

had been the better suited for the Phase Two flight tests planned by 

AFSC and NASA. It had a better wing configuration, better inlet ramp 

control system, and much better instrumentation. It was gone. AFSC 

doubted that the first XB - 70A could meet the same goals and, indeed, 

when testing resumed, it never ventured beyond mach 2.57. On 3 

November 1966 Joe Cotton and NASA pilot Fitz Fulton” took the 

remaining XB-70A over an instrumented test range for boom assessment at mach 2.1. The plane made 10 more flights by the end of January 

1967.13 

That same month the Air Force, after comparing cost with research 

utility, decided to transfer total program and funding responsibility for 

flight, the big aircraft remained down for maintenance for 2% months. 

During that time, Air Force and NASA officials worked out the details of 

the transfer. On 15 March NASA and Air Force representatives signed 

an agreement under which the Air Force would continue to run some 

XB - 70A research projects and provide aircraft support and pilot 

participation. A week later, FRC Director Paul Bikle and AFFTC 

commandant Maj. Gen. Hugh Manson created a joint FRC-AFFTC 

XB - 70A operating committee patterned on the very successful X- 15 

and lifting body agreements. Expenditures up to this point had amounted 

to approximately $2 million per month; to stay within its available 1967 

and 1968 spending rates, NASA limited its planned XB-70A monthly 

program expenses to $800 000 per month, which automatically cut back 

the planned flight program. The agency had requested $10 million in 

FY 1968 funding, sufficient to continue the program through 1968. Also, 

FRC awarded an $8.9 million contract to North American for maintenance 

and support of the XB-70A while it was flown by NASA and a 

$l.g-million contract to General Electric for engine maintenance.’* 

the XB-70A to NASA “as soon as possible.” Following its last Air Force u 

*Fulton, a former senior Air Force test pilot on the XB-’IOA, had retired from the Air Force. 

He had launched most of the early “Round One” rocket airplanes from B-29 and B-50 

motherships while flying for the Air Force. Fulton was a welcome addition to the FRC pilots’ office, 

for he was the world’s finest test pilot of large multiengine supersonic airplanes. 

185 
li c 

ON THE FRONTIER 

During its 11 flights from November 1966 through January 1967, 

the XB-70A supported the National Sonic Boom Program. This program, 

begun in June 1966, had involved a number of military aircraft inflights 

over selected American cities. The XB-70A made these flights at 

different weights, altitudes, and mach numbers over a test range at 

Edwards instrumented to record the “boom carpet” of the aircraft and its 

“overpressure” (pressure rise) on two specially constructed test houses. 

Such studies were critical; while the boom of a supersonic fighter 

might do little more than annoy citizens, the possibility existed that a 

large heavy SST would lay down a boom of such magnitude that it might 

do serious damage. During the XB-70A’s tests, the craft made one 

overflight at mach 1.22, 192 000 kilograms weight, and an altitude of 

8200 meters, generating an overpressure of 150.8 newtons per square 

meter (3.15 lb/sq ft). Higher, at 21 300 meters, the XB-70A once 

generated a boom having 11 1.6 newtons per square meter (2.33 lb/sq ft) 

overpressure directly underneath the aircraft, and an overpressure of 

77.8 newtons per square meter (1.71 lb/sq ft) up to 13 kilometers to 

one side of the plane. An overpressure of 3 18 newtons per square meter 

(7.5 lb/sq ft) is sufficient to damage some structures. During turns, the 

XB -70A’s shock waves converged, often doubling the overpressure felt 

on the ground. The tests clearly indicated that much work remained on 

tailoring aircraft design to minimize shock wave magnitude; even though 

the booms were not materially damaging, they were annoying. Indeed, 

the XB - 70A tests went far toward providing quantitative evidence that 

overland commercial SST operations at supersonic speeds would generate boom phenomena that simply would not be t01erated.l~ 

When the XB-70A returned to the air in April 1967 on its first 

NASA flights, the agency had mapped out another program for the 

airplane: acquiring flight data that could be used to correlate and validate 

the data from two SST simulators, a ground-based simulator at Ames 

Research Center and FRC’s Lockheed Jetstar general-purpose airborne 

simulator (GPAS). NASA also had the XB-70A aircraft instrumented to 

record information on aeroelastic response of the structure to gusts; 

handling qualities, especially during landing approach; and boundary 

layer noise. NASA engineers believed that the combination of XB-70A 

tests and tests of the GPAS aircraft could benefit the development of 

Boeing’s proposed SST in four key areas, including control in the event of 

engine failure at supersonic speeds, development of an SST stability 

augmentation system, derivation of longitudinal stability requirements, 

and the influence of “ground effect” upon the landing characteristics of 

an SST. Later FRC added other programs to investigate inlet performance and structural dynamics, including fuselage bending and canard 

flight loads.16 

186 
MACH 3 AGAIN 

Fitz Fulton and Joe Cotton completed the XB-70A’s first NASA 

flight on 25 April 1967. By the end of March 1968, the plane had 

completed a further 12 flights by Fulton, Cotton, Van Shepard, Lt. Col. 

Emil “Ted” Sturmthal, and NASA pilot Donald Mallick. Following the 

73d flight on 2 1 March, NASA grounded the airplane for installation of a 

structural dynamics research package dubbed ILAF-meaning identically located acceleration and force. Two small, thin exciter vanes 

extended 60 centimeters outward from just in front of the crew 

compartment. They could rotate 12” at a frequency up to 8 cycles per 

second. The vanes induced structural vibrations having a known frequency and amplitude; accelerometers sensed the disturbances and 

signaled the aircraft’s stability augmentation system to move the aircraft’s 

controls and suppress the disturbance. NASA hoped the ILAF program 

would serve as a prototype for advanced systems that could be installed 

on SSTs, enabling them to fly with increased smoothness, reducing the 

fatigue experienced by both passengers and airframe. Previously XB - 70A 

crews had frequently experienced annoying trim changes and buffeting 

from clear air turbulence and rapidly fluctuating atmospheric temperature. 

Test results indicated’ that the ILAF system reduced the buffeting 

associated with such conditions. The XB-70A made its first ILAFequipped flight on 11 June 1968; from then until the end of the program 

in 1969, the aircraft acquired a great deal of information applicable to 

the design of future SST or large supersonic military aircraft. ’’ 

By the end of 1968, operating expenses and maintenance problems 

had caught up with the XB-70A. The research data gained from the 

plane no longerjustified the resources needed to maintain and operate it. 

The Flight Research Center could look forward to operating another 

mach 3 + airplane, the Lockheed YF- 12A Blackbird, which represented a 

more advanced technology than that of the already dated XB-70A. On 

13 January 1969, NASA Headquarters announced termination of the 

joint NASA-DoD XB - 70A flight research program. The announcement 

rightly hailed the XB-70A as “a productive flight research vehicle for 

studying sonic boom, flight dynamics, and handling problems associated 

with the development of advanced supersonic air~raft.”’~ On 4 February 

1969, the Valkyrie made its last flight, to Wright-Patterson AFB, Ohio, 

where it is now on exhibit at the Air Force Museum.lg Together the two 

XB-70A aircraft had completed 129 flights. The first XB-70A had 

completed 83 of these. The total flying time for both airplanes had been 

252 hours, 38 minutes. Of this, 22 hours were spent above mach 2.5. 

Today visitors at the Air Force Museum can compare the XB-70A to 

other dinosaurs of flight. The Valkyrie is still an impressive sight.*’ 

Thus ended the XB-70A program. Without a doubt, the loss of the 

second aircraft hurt whatever results NASA and the Air Force could have 
ON THE FRONTIER 

expected to reap out of this long time- and budget-consuming project. 

Critics of the aircraft often fail to realize, however, just how ambitious the 

XB-70A was. It was the world’s first large transport-size aircraft 

capable of sustained, long-range supersonic flight. So intoxicating were 

its performance figures that in 1959, the FAA administrator, Gen. 

Elwood Quesada, recommended to President Eisenhower that the United 

States develop a commercial version of the aircraft. While this proposal 

went nowhere, North American naturally drew quite heavily on its 

XB-70A work when developing its own abortive SST plans. Critics also 

fail to recognize that the aircraft did return a great deal of information 

on sustained supersonic cruise. The data predicted SST behavior, which 

could be incorporated in simulators, and the structural and control 

requirements of such airplanes. The flight requirements for a mach 3 

SST are far more complicated than the requirements for a mach 2 SST. 

The magnitude of the problems is easily determined by noting that the 

Anglo-French Concorde, a modest mach 2 airplane, is the product of one 

of the greatest international cooperative industrial efforts conceived to 

this time. The problems of mach 3 present an even greater engineering 

challenge. Designers of mach 3 aircraft cannot use a conventional 

aluminum airframe. Rather, because of aerodynamic heating, they must 

use sophisticated and challenging material such as titanium. Controlling 

an aircraft moving at mach 3 and integrating it into an air transport 

network with aircraft moving much slower than it does also presents 

problems. It is remarkable that the XB-70A achieved the performance it 

did though it was the first U.S. venture into large supersonic aircraft 

design. 

NASA’s Flight Research Center engineers had always hoped that the 

center could play some role in the development and testing of Boeing’s 

SST, seeing such activity as the logical conclusion of the center’s work 

with the XB-70A and GPAS programs. In September 1967, center 

engineers prepared a rough proposal for the FAA and NASA Headquarters enumerating a variety of areas where the FRC could assist the FAA 

and Boeing on development of the airplane. In some of the areas-such 

as studies on pressure drag, skin friction, surface roughness, shock waveboundary layer interaction, and boundary layer noise-Boeing and the 

FAA had no research efforts under way, while FRC’s experience and 

background were unique.*l 

The American SST fell further and further behind its European 

competitors as cost and complexity rose. Even before the XB-70A 

concluded its flying program, the first supersonic transport, the Soviet 

Tu- 144, had completed its maiden flight. One month after the XB-70A 

retired, the Anglo-French Concorde took to the air. In contrast, the 

Boeing design was in serious difficulty, including numerous major design 

changes, such as going from a variable sweep wing to a fixed modified 

delta-a bad sign. Though the American SST had the full support of 

188 
MACH 3 AGAIN 

three successive presidents-Kennedy, Johnson, and Nixon-it had 

numerous critics, ranging from thoughtful spokesmen who questioned its 

economic utility to neo-Luddites operating simply from an antitechnological 

bias. To save the foundering program, the FAA created, at the behest of 

President Nixon, an Office of the Supersonic Transport. This office, 

directed by William M. Magruder, a distinguished test pilot and, ironically, 

former technical director of Lockheed’s own SST design, did its best to 

keep the Boeing SST alive, but to no avail. On 24 March 1971, the Senate 

declined to appropriate $289 million for prototype fabrication, abandoning the field to Concorde and the Tu- 144. 

Since that time, industry had continued work on developing the 

technology necessary for an American SST. Dryden Flight Research 

Center engineers have kept in touch with these efforts. Nevertheless, the 

driving impetus that characterized the earlier SST effort is missing. The 

Arab oil embargo of 1973 and the subsequent high cost of jet fuel have 

increasingly made a petroleum-fueled SST look like a money-losing 

liability. Should an SST-or even a hypersonic transport-be developed 

in the future, it might well be fueled by liquid hydrogen. Such an aircraft 

could enter commercial service around the turn of the century, but it 

would require a major national investment and the greatest possible 

cooperation between private industry and the Federal government.22 

When the XB-70A program concluded, hopes were still high that 

the United States might produce an SST for the 1970~~ and the 

program’s end did not end FRC’s work on advanced supersonic cruise 

aircraft. Indeed, the center terminated the XB-70A to make way for an 

even more advanced vehicle: the Lockheed YF- 12A Blackbird. The first 

NASA FRC research flight on the YF-12A took place in 1969, but by 

that time center engineers had already been supporting the Air Force on 

the Blackbird program for two years. That program quickly took up 

where the XB-70A program had left off. 

NASA AND THE BLACKBIRDS 

Even though two decades have passed since the first flight of the 

Blackbird series, this program is shrouded in secrecy. Conceived by the 

Lockheed company to fulfill a requirement for a mach 3+ strategic 

reconnaissance aircraft, the program spawned two similar configurations, 

the YF- 12A, an abortive interceptor, and the SR-71A, a long-range 

reconnaissance aircraft. Exact performance figures are still highly classified; 

official sources still only refer to the planes as mach 3 vehicles capable of 

flying at 24 400 meters. Their true performance may be quite a bit higher 

than these conservative statistics. 

The Blackbirds came out of the Lockheed Advanced Development 

Projects Group, the famed “Skunk Works” headed by Clarence “Kelly” 

189 
ON THE FRONTIER 

Johnson. Considering the scope of the technical challenges, the Blackbirds offered unparalleled design difficulties that Johnsan and his team 

of fewer than 200 engineers overcame. Because of the sustained high 

temperatures that the planes would encounter during mach 3 cruise, 

Johnson chose a largely titanium airframe. All supporting systems and 

fluids, including lubricants and fuels, had to be developed from scratch. 

During mach 3 + cruise, the afterburning turbojet engines functioned 

more as ramjets than as gas turbines. The first Blackbird flew at a remote 

airstrip in 1962, and flight tests generally went smoothly. Though flown 

in single- and two-place versions, Lockheed standardized on a two-place 

configuration, with a pilot and navigator-systems operator. The plane 

featured a distinctive, blended wing-body shape, with long chines running along the fuselage sides from the wing roots. Each engine was 

located at mid-span, and each nacelle was surmounted by a large, 

inwardly canted, vertical fin. For additional stability, the YF- 12A had a 

folding ventral fin and two smaller, fixed ventral fins as well. In February 

1964 President Lyndon Johnson announced the existence of the plane. 

The first of the definitive reconnaissance variants, the SR-71AY flew 

later that same year.23 

The Flight Research Center’s involvement with the Blackbird program began in 1967. Ames Research Center had opened negotiations 

with the Air Force for access to the early YF-12 wind-tunnel data that 

had been generated at Ames under extreme secrecy. The service agreed, 

in return for NASA assistance on the flight test program then under way 

at Edwards. This arrangement closely dovetailed with the plans of 

OART, which saw the Blackbird as a means to advance high-speed 

technology, especially that necessary to build SSTs. In the summer of 

1967, the Air Force and NASA agreed to Flight Research Center 

participation. Paul Bikle and FRC research chief Joseph Wed asked 

engineer Gene Matranga to represent NASA on the Blackbird test force. 

Matranga, then busily involved in general aviation studies, thought about 

it over a weekend and agreed to go. Bikle, Weil, and Matranga assumed 

the center would work with the Air Force on the project for about six 

months. The exposure would give FRC engineers data to compare with 

the flight results coming from the XB-70A program. Matranga began 

working on Blackbird stability and control and soon brought a small team 

of experienced FRC engineers to labor along with him. Much good will 

between the Air Force, Lockheed, and NASA test force team members 

ensued. 

The service team needed assistance in several technical areas. The 

Air Force wanted to get the SR-71A fully operational with the Strategic 

Air Command as quickly as possible. NASA wanted an instrumented 

SR-71A for the agency to use for its own research; failing that, NASA 

was willing to install an instrument package on the Air Force SR-71A 

190 
P 

MACH 3 AGAIN 

stability and control test aircraft. The Air Force declined, but offered 

NASA use of two YF-12A aircraft then in storage at Edwards. NASA 

quickly assented, even taking the unusual step of paying the operational 

expenses of the airplanes, using funds made available by termination of 

the X-15 and XB-70 programs. The service would also furnish a test 

team from the Air Defense Command for maintenance and logistics support. A memorandum of understanding was signed 5 June 1969; public 

announcement came on 18 July. Matranga and the FRC team immediately set to work instrumenting the two YF-12A aircraft and mapping 

out a joint program with the Air Force.24 

At FRC and Ames, interest was high in Kelly Johnson’s Blackbird. Its 

airframe, propulsion system, and related equipment most engineers 

expected to see on future mach 3 airplanes. It was an ideal vehicle for 

assessing the state of the art of wind-tunnel prediction, aerodynamics, 

propulsion, and structural design. The plane could also carry experimental research packages, but FRC considered this a secondary objective, at 

least at first. Langley engineers had interest in running fundamental 

aerodynamics experiments and tests of advanced structures. Lewis was 

interested in propulsion research. Ames, a vital partner to FRC, was 

interested in inlet internal aerodynamics and the correlation of windtunnel and flight data. Flight Research Center thus had the challenging 

task of organizing these interests into a single unified research program. 

At first, FRC concentrated on aerodynamic loads and structural effects 

because instrumentation was available for those investigations. Much 

time-consuming work remained to be done before one of the Blackbirds 

could be instrumented for propulsion tests. So when the Air Force brought 

the two YF- 12As out of storage, FRC technicians installed strain gauges 

and thermocouples. They instrumented the wing and fuselage for aerodynamic loads and the left side of the aircraft for temperature measurements to better define the craft’s thermal en~ironment.~~ 

NASA and Air Force technicians spent three months readying the 

first of them for flight. On 10 December 1969, the joint flight research 

program got under way with a successful maiden flight. The first 

YF- 12A ready quickly became the program’s workhorse, while technicians readied its stablemate.* With the first flight out of the way, the 

NASA-Air Force team got down to the serious business of acquiring 

data points. While the Air Force concentrated on military applications, 

such as studying bomber penetration tactics against an interceptor having 

YF- 12A capabilities, NASA pursued a loads-research program. FRC 

*These two aircraft were the second and third YF-12As actually built; the second, serial 

number 60-6935 became NASA’s long-lived YF- 12A. The third, 60-6936 crashed and was 

replaced by the YF-l2C, 60-6937. 

191 
a 

ON THE FRONTIER 

and Langley engineers were interested in measuring the flight loads, 

which depended on both the actual load conditions and the effects of 

structural heating. At some future date, FRC engineers planned to move 

the airplane into FRC’s High Temperature Loads Laboratory, heat it, 

and determine how much of the load stemmed from thermal heating of 

the structure. This is not an innocuous as it sounds. When an airplane’s 

structure is heated, the induced thermal stresses change the shape of the 

structure even without loads being applied. The changed airframe shape 

then has a much different load distribution pattern. When actual flight 

loads are added, the importance of knowing how the structure reacts to 

temperature and load is self-evident. To predict loads and structural 

response, NASA had developed two computer modeling programs using 

a technique known as finite element analysis. Both programs, FLEXSTAB 

and NASTRAN, were applied to the YF-12A. One of the major 

objectives of the flight tests on the Blackbirds was to compare the actual 

flight test results with the predicted data. Technicians also installed a 

Hasselblad camera within the fuselage of the YF- 12A to photograph the 

structure during high-g maneuvers, recording the deformation of the 

aircraft. Under certain conditions, the camera revealed that the plane 

experienced as much as 15 centimeters of deflection at the aft end of the 

fuselage.26 

While the program on aircraft 935 went smoothly, the program on 

936, the other YF- 12A, ended badly. The aircraft had just embarked on 

its joint NASA-Air Force research program when it crashed. During a 

flight 24 June. 197 1 to acquire operationally useful information, this 

Blackbird experienced fatigue failure of a fuel line and fire in the right 

engine. Lt. Col. Ronald J. Laytdn and systems operator Maj. Billy A. 

Curtis debated whether they could land the burning Blackbird. They 

wisely elected to eject, and the YF-12A smoked down to an explosive 

finale.27 The loss of the YF-12A did not seriously affect the NASA 

structures program, which was almost finished; it did delay plans for the 

propulsion research program. NASA had wanted to add a third aircraft 

to the YF- 12A joint test program, solely for propulsion tests. A month 

after the loss of the YF-l2A, the Air Force made available 937. This 

aircraft, which was designated YF- 12C, had SR-7 1A features; because 

the SR-71 program was shrouded in the highest security classification, 

the Air Force restricted NASA to using the aircraft solely for propulsion 

testing with YF- 12A-model inlets and engines in place of the presumably more sophisticated inlets and engines on the SR-71A. The YF- 12C, 

which looked like the SR-71A, was thus an oddball. For the NASA 

programs on both the YF-12A and YF-126, the Flight Research 

Center had designated pilots Fitz Fulton and Don Mallick and flight-test 

engineers Vic Horton and Ray Young. As the program developed, 

generally Fulton and Horton flew together as one team, Mallick and 

192 
MACH 3 AGAIN 

Young as the other. At Beale AFB, the pilots received familiarization 

flights in a humpback SR-71B having a second pilot cockpit in place of 

the navigator-systems operator’s cubicle.28 

On 24 May 1972 Fulton and Horton crewed the YF- 12C on its first 

NASA flight. By this time, NASA had already accumulated 53 flights in 

the YF- 12A and had grounded the airplane for testing in FRC’s High, 

Temperature Loads Laboratory. It remained in the lab for over a year, 

not flying again until July 1973. As a result of the correlation between 

flight tests and tests in the heat laboratory, FRC engineers were confident 

that they had developed instrumentation and test procedures that would 

allow the aircraft industry to proceed with assurance on the development 

of other high-temperature aircraft. 

NASA engineers approached the propulsion program on the YF- 12C 

with a similar purpose in mind: “provide a baseline of information that 

can be used in future times as well as the present time to assess the 

validity of current prediction and wind tunnel test technique^."^' Together with Pratt & Whitney (the engine manufacturers) and Lockheed, 

FRC engineers assembled a computer model of the engine and inlet 

system. In conjunction with Ames, Langley, and Lewis research centers, 

the flight data of the aircraft were compared with data taken from tests of 

scale-model inlets; also a full-scale inlet was tested in the Lewis 10 x 10- 

foot tunnel in early 1972. One surprise was the discovery that a strong 

vortex, coming from the fuselage chines, streamed into the middle of the 

inlet. These studies were very detailed, examining such questions as what 

percentage of airflow through the inlet left through bypass doors in the 

inlet and what percentage actually passed through the engine. The FRC 

team also examined inlet “unstart”-if the airflow was not properly 

matched to the engine, internal pressure would force the standing shock 

wave from inside to outside the inlet. This action lost the thrust provided 

by inlet pressure recovery; the thrust imbalance generated a large yawing 

motion, as well as residual pitching and rolling tendencies. The first time 

one NASA crewman encountered unstart, the aircraft motions and 

accelerations were so violent that he expected the YF-12 might break 

up. Obviously this condition could not be tolerated on an SST aircraft. 

NASA devoted a great deal of attention to unstart in an attempt to learn 

how to control it, deliberately inducing unstarts on test flights. Automatic 

inlet sensing and control was one method of combatting it; the production SR-71A’s system worked so well that the Air Force had to induce 

the phenomenon to familiarize pilots with it during training. NASA’s 

YF- 12 crews became so familiar with unstarts that they could sense when 

one was imminent even before the instrumentation showed it.30 

The FRC YF- 12 program was ambitious; the aircraft flew an average 

of once a week unless down for extended maintenance or modification. 

Program expenses averaged $3.1 million per year just to run the flight 

193 
ON THE FRONTIER 

tests, and Ames, Lewis, and Langley were heavily involved in the program 

as well. The YF- 12A program dominated the annual FRC Basic Research 

Review reports that the center prepared for OAST’s Research Council 

during the 1970~.~’ The scope of what was involved in a YF-12 flight 

was enormous. Technical preparation and briefings aside, the flights. 

required coordination of the highest order between NASA, FAA, and 

Air Force. The crew would suit up 1% hours before takeoff, using a 

special Air Force aeromedical van, drive out to the flightline, and enter 

the aircraft. For what seemed an interminable time they would run up 

the engines and check out systems. The Blackbirds-and sometimes both 

would fly together-would sit on the ramp, engines oddly muted, exhaust waves shimmering over the lake. Other FRC personnel would 

ready an F- 104, and maybe a slower T-38 as well, to follow the craft on 

takeoff and acceleration to mach 2. Further north, at Beale AFB, the Air 

Force would send aloft a KC- 135Q tanker with a load of the Blackbird’s 

special JP-7 fuel. Finally all would be ready; one after another, the 

aircraft would taxi from the Flight Research Center to the 4600-meter 

runway. After final safety checks, the Blackbirds would scoot down the 

runway and rumble into the air with a shattering roar reminiscent of a 

Saturn V booster. The chase planes would follow. The YF-12A would 

accelerate to about mach 0.9, dive (the most efficient way to exceed mach 

l), nose upward, and accelerate to the maximum speed selected for the 

flight, outrunning and outranging the chase. After one gigantic circuit 

over the western U.S. (with the Air Force and FAA keeping a watchful 

eye to make certain that the craft did not wander around other SR-71As 

or U-2s tooling about in the sky), the Blackbird would decelerate and 

descend, take on a load of fuel from the KC- 135Q, again go supersonic, 

make another circuit, then return and land. 

NASA’s Blackbird program had its exciting moments, routine unstarts 

aside. On one YF- 12C flight, Don Mallick and Ray Young experienced a 

stuck inlet spike, which caused the airplane to burn prodigious amounts 

of fuel, necessitating an emergency landing at Fallon Naval Air Station, 

Nevada. Another time, during a stability test at mach 0.9 with the craft’s 

roll and yaw stability augmentation system deliberately off, they lost the 

folding ventral fin from NASA’s YF- 12A. Fortunately this fin is needed 

only at high supersonic speeds; at mach 3 the effect would have been 

much more serious, probably loss of the airplane. Mallick and Young 

skillfully brought the ailing airplane back to Edwards. The departing fin 

had damaged the wing, aft fuselage, and stability augmentation system; it 

also ruptured a fuel tank, causing it to dump its contents overboard in a 

long silver trail. 

Tests of a proposed “coldwall” experiment package gave bad moments as well. The coldwall, a Langley-supported heat-transfer experiment, 

194 
MACH 3 AGAIN 

consisted of a stainless steel tube equipped with thermocouples and 

pressure-sensing equipment. A special insulation coating covered the 

tube, which was chilled with liquid nitrogen. At mach 3, so planners 

hoped, the insulation could be pyrotechnically blown away from the tube, 

instantly exposing it to the thermal environment. Its data could be 

compared with results taken from testing a similar tube using groundbased wind-tunnel facilities and would validate ground research methods. 

Eventually researchers did get a successful test, but the experiment 

caused numerous in-flight difficulties. On the last coldwall flight, for 

example, the YF- 12A experienced a simultaneous unstart followed by 

rough engine operation after firing the coldwall. As it descended, 

anxiously followed by the YF- 126 photo chase plane, the latter aircraft 

also experienced multiple unstarts; for a brief while, test monitors at 

Dryden worried for the safety of both crews. Both aircraft limped back to 

Edwards at reduced power. NASA grounded them for extended 

in~pection.~~ 

Flight tests of the YF- 12 aircraft furnished some interesting data. 

For example, at mach 3 fully 50% of the aircraft's total drag came from 

NASA3 YF-12A Blackbird cruises over the desert carrying a '%oldwall" heat-transfer 

experiment under the fuselage. 

195 
ON THE FRONTIER 

simply venting air overboard through the inlet bypass doors. Also, a gray 

area was discovered between stability and control, on the one hand, and 

propulsion, on the other. Inlet components were almost as effective as 

ailerons and rudders in influencing aircraft motion at high speeds; inlet 

spike motion and bypass door operation could alter the aircraft’s flight 

path under some conditions. The airflow dumped overboard through 

the inlet louvers entered a “stagnation area” just ahead of the louvers and 

actually flowed forward along the outside of the nacelle for a brief 

distance before mixing with the mach 3 airstream and moving aft-a 

weird effect. Most serious, however, was a problem that had earlier 

cropped up on the XB-70A: unwanted altitude changes, while cruising 

at high altitude and high speed. 

In fact, the main stability and control area of interest to NASA 

researchers was the ability to hold a desired cruise altitude. At high 

speeds and altitudes, without stability augmentation, the plane could 

change attitude slightly; since it was moving at mach 3, any nose-up or 

nose-down change immediately produced major changes in altitude. The 

plane entered porpoising motions for up to three minutes, during which 

altitudes changed by as much as plus or minus 1000 meters. Such 

operation would certainly be prohibitive from an air traffic control 

standpoint with a commercial SST aircraft. At the altitudes the YF- 12s 

and SR-71As operated, there was no other traffic aside from an 

occasional U-2 or fellow SR-71A; but that situation could change with 

time. The thought of fleets of SST aircraft all wobbling about their flight 

paths is not comforting. The YF- 12’s very ability to attain high speeds 

and altitudes contributed to the problem. At mach 3, it covered distance 

quickly, passing through local pressure and temperature changes that 

would affect a slower aircraft much more gradually. Since mach number 

is a function of pressure and temperature, the rapid variations caused 

velocity changes; correcting for these changes by adjusting inlet controls 

or aerodynamic controls produced large altitude deviations. In future 

supersonic transports, such a situation would pose problems for air 

traffic controllers and in some circumstances could cause the aircraft to 

exceed its operating limits.33 

As one potential solution to the altitude-holding problem, FRC 

engineers developed a new autopilot and flight-tested it on the YF- 12s. 

Traditional autopilots moved aerodynamic control surfaces to maintain 

speed or altitude. The experimental YF- 12 system compensated for 

various pressure-sensitive instrumentation that influenced altitude 

deviations; after further modifications, it linked the aircraft’s central 

air-data computer to the autopilot, the inlet control system, and the 

engine throttle system. The combination of aerodynamic surface controls 

and throttle control, together with more advanced data sensing equipment, 

worked well on actual flight tests, even during extended high-mach 

196 
MACH 3 AGAIN 

cruise.34 Such integrated systems would almost certainly be used on 

future SSTs. 

NASA performed a variety of research on the Blackbirds. For 

example, technicians installed a special computerized checkout system in 

the aircraft, the central airborne performance analyzer. CAPA monitored a number of parameters dealing with aircraft maintenance, including the craft’s electrical system, inlet control system, and hydraulic 

system. Though just a research project itself, CAPA offered great 

promise for such future projects as the Space Shuttle and commercial and 

military aircraft. During flight, the system could actually diagnose a 

problem, informing the pilot whether he should abort. At the end of the 

flight, technicians could check the CAPA readout to determine the 

maintenance required before the next flight. 

Another program investigated the temperature, pressure, and other 

physical characteristics of the upper atmosphere, because such factors 

would have great impact on the performance and operation of future 

aircraft. FRC examined high-altitude turbulence, which the YF- 12s 

encountered at virtually all altitudes, and researchers supported the work 

with statistical studies at the National Climate Center and the University 

of California at Los Angeles. Biomedical researchers took physiological 

and biomedical measurements of the flight crews on most YF- 12 flights 

to derive a better understanding of physiological stress. Researchers used 

the airplane as a flying wind tunnel carrying experiments and instrumentation for studying boundary layer flow and noise, heat transfer, skin 

friction, and base pressure measurements. Under Langley Research 

Center’s supersonic cruise aircraft research program, FRC evaluated a 

number of advanced structural techniques on the YF- 12. Engineers 

replaced a panel on the airplane with a series of Langley-designed 

experimental panels of advanced design. The flight testing complemented laboratory work on small test specimens. Technicians chose a test 

panel, sized 71 by 41 centimeters, on the inboard upper surface of the 

wings between the nacelle and the fuselage. Between 1974 and 1976 they 

evaluated three lightweight structures there: a weldbrazed titanium skin 

stringer panel, a titanium honeycomb-core sandwich panel, and a 

sandwich panel faced with boron-aluminum and having a titanium 

honeycomb core. All exceeded required strengths. In all these ways and 

more the Blackbirds contributed to flight technology. Because of the 

tight security restrictions on the program, engineers could get information only on a “need-to-know” basis. Nevertheless, in June 1974 the 

Flight Research Center hosted a major conference attended by 150 

representatives from government and the aviation industry to report on 

the YF-12 loads research. Though it had been over a decade since the 

first flight of the Blackbirds, they still represented advanced state-of-theart te~hnology.~~ 

197 
ON THE FRONTIER 

BLACKBIRDS, BYE-BYE I 

By the beginning of 1977, the YF-12 aircraft had completed over 

175 flights, much of the time above mach 3. Though still the pride of 

Dryden’s hangars, the two Blackbirds were becoming increasingly expensive to maintain and more difficult to justify. Other programs-notably 

the center’s McDonnell F- 15 Eagle research aircraft-could lay greater 

claim to funding. The axe fell during an OART center directors’ 

management council meeting in the spring of 1977. Residual funding 

enabled the YF- 12C to fly through October 1978, continuing tests of an 

integrated aerodynamic and propulsion control system. The oldest 

YF-12 still flying, 935, would end its research program a year later.* 

Dryden’s most visible program thus ended far sooner than most YF- 12 

partisans had assumed-previously, the center had planned to operate the 

Blackbirds into the 1980~~~ 

The decision was not popular with the YF-12A team; they saw 

themselves as the center’s elite program, and tended to view the cancellation as more evidence that Dryden’s “Golden Years” were in its past and 

not its present. Many decried what they felt to be a growing tendency 

within the agency to homogenize the centers, reducing center control 

over research. The fiercely independent NACA veterans shook their 

heads in frustration. Partisans grumbled that the decision was simply the 

latest in a long line afflicting a technological hiatus on American aviation, 

and as evidence pointed to the SST cancellation. When the B- 1 and 

NHFRF joined the ranks of the pad, the YF- 12 decision became just 

one more name in the litany of martyred projects. The decision, 

however, was final. For the time being, Dryden was through with mach 3. 

NASA’s Blackbird program proved one of the most useful programs 

ever flown at the center. It was the major airbreathing propulsion work 

done at Dryden and helped change the center’s image away from a rocket 

bias toward a more balanced mix of research. The Blackbird program 

was certainly much more productive than the XB-70A; the two YF- 12s 

proved surprisingly free of chronic maintenance problems, aside from 

some difficulties with fuel tank leaks. The program generated a great 

deal of information that will prove useful to future mach 3 sustainedcruise designs. To those unacquainted with the flight testing process, it 

often seems odd that so much effort should be spent testing modified 

versions of production designs. Surely, the criticism goes, the contractor 

and the user have already obtained all the information of value from the 

aircraft by the time another agency or group acquires it. The YF-12 

program is a good example of how incorrect this supposition is. The 

contractor and the user were naturally much more interested in assuring 

*Appendix P contains a chronology of YF-12 flights. 

198 
I "3 * I a 

MACH 3 AGAIN 

that the aircraft was safe to operate and met its performance specifications. 

When the SR-71A entered full service with the Strategic Air Command, 

Air Force interest in the craft's research utility quickly cooled. A 

contractor is never in a financial position to run an extended flight 

research program, no matter how beneficial it might be later on. And so 

it fell to NASA to use the Blackbirds as research instruments. The 

Blackbird teams derived an important data base for subsequent aircraft 

design. Interest in supersonic flight was already ebbing at Dryden by 

1979, but the engineering staff was busily working on a variety of other 

problems from transonic research to remotely piloted research vehicles, 

maintaining the center's reputation for diversity. 

199 
A a 
10 

A Center with Diversity: 1962- 1981 

In the last two decades, the Flight Research Center undertook 

aeronautical studies covering a wide range of research areas. This work 

continued FRC’s tradition of simultaneously running diverse research 

programs, supporting civil and military aircraft testing and development, 

and supporting research in progress at other NASA centers, the latter 

usually by “proof of concept” flight testing. During these years, engineers 

and technicians evaluated the Whitcomb supercritical wing and winglet; 

developed a new flight research tool, the remotely piloted research 

vehicle; developed and evaluated a radical new method of flight control 

using electronics; studied wake vortex formation and clear air turbulence, 

two areas of importance to aviation safety; supported development of 

new military aircraft systems; and entered a number of other fields as 

well, including design configurations for long-distance trailer trucks and 

flight testing of advanced rotorcraft. Though much of the center’s 

research was applied, more of it was basic, exploring and deriving new 

data on the often mysterious and perplexing conditions and phenomena 

that influence how flight vehicles perform.’ The full spectrum of 

FRC’s research in aeronautics is shown in figure 5. 

FRC AND THE SUPERCRITICAL WING 

In 1978, over three decades since Chuck Yeager exceeded mach 1, 

John Anderson, a noted aerospace engineering educator, wrote: 

The analysis of transonic flows had been one of the major 

challenges in modern aerodynamics. Only in recent years, since about 

1970, have computer solutions for transonic flows over airfoils come 

into practical use; these numerical solutions are still in a state of 

development and improvement. Transonic flow has been a “hard nut 

to crack.”2 

Though the transonic regime had long disappeared as a “barrier” in the 

minds of engineers, it continued to fascinate aerodynamicists. In the 

20 1 
* 

I XB-70A 

YF-12AIC 

II F-8 SCW 

F-111 TACT 

KC-135 Winglet 

Hyper 111 

PA-30 RPRV 

F-15 RPRV 

Mini-Sniffer 

HiMAT 

IV F-8 DFBW 

F-111 IPCS 

111 “Mother” 

V Lightplanes* 

7471L-1011 Vortex 

6-57 CAT 

VI F-4 

F-1llA 

Agility Studies’ 

F-15 

YF-17 

F-14 

ON THE FRONTIER 

- - - 

- - - w 

- - - 

- - - 

- 

- - ___t 

- * 

- D 

- - 

- - - 

- 

- - - 

- - - D 

- - - -D 

IIIIIIII1 

1962 64 66 68 70 72 74 76 78 80 

I = Supersonic Research 

I1 = Transonic Research --t Ongoing program 

111 = Remotely Piloted Research Vehicles 

IV = Electronic Flight Controls 

V = Aviation Safetv 

*Tests of various small 

general-aviation aircraft 

VI = Service Aircraft Programs Tests of various fighters 

for developing future 

agility requirements 

Figure 5. D?yden Flight Research Center aeronautical research programs, 1962 - 1980. 

transonic regime, an airplane experiences mixed subsonic and supersonic flow patterns. At some point, which varies with the design of the 

plane, the flow over the wings goes supersonic; a little faster and standing 

shock waves dance across the wing; then the drag of the plane rises 

sharply with concomitant losses in efficiency. It is also in the transonic 

regime that most commercial jet airliners fly, so the intricacies of 

transonic aerodynamics are part of the real world for aircraft designers. 

One individual who devoted the major portion of his NACA-NASA 

career to transonic research was Langley’s Richard T. Whitcomb, an 

engineer fond of remarking, “We’ve done all the easy things-let’s do the 

hard ones.” In the 1950s, Whitcomb had derived the concept of transonic 

area rule, which gave an entire generation of aircraft a “wasp waist” or 

pinched look. An engineer equally at home with a slide rule at his desk or 

shaping a wind-tunnel model for testing, Whitcomb demonstrated an 

202 
A CENTER WITH DIVERSITY 

uncanny ability for visualizing configuration changes to enable airplanes 

to fly more efficiently at transonic speeds. He ultimately conceived two 

other means of improving that efficiency: the supercritical wing (SC W) 

and the wingtip “winglet.” All three advances went to the High-speed 

Flight Station (later the Flight Research Center, later still Dryden) .for 

“proof of concept” flight testing. 

During the early 1960~~ Whitcomb investigated a technique for 

tailoring airfoil designs to raise the drag-divergence mach number as 

close to the speed of sound as possible. Such airfoils would have a 

“supercritical” mach number, the point at which the airflow over the 

airfoil exceeds the speed of sound. They would have less drag, because 

the design would discourage shock-wave formation. In other words, if 

two transports of similar design cruised at the same speed, differing only 

in that one had a conventional airfoil and the other a supercritical airfoil, 

the transport with the supercritical airfoil should have less drag, and 

hence should use less fuel. It should also have higher speed potential 

and, because of its fuel efficiency, greater range. Whitcomb estimated 

that such airfoils could raise the cruising speed of long-range jetliners by 

as much as 160 kilometers per hour. He embarked on a four-year 

wind-tunnel study program at Langley. The shape he finally selected had 

a flattened top surface, with a downward curve at the trailing edge; it 

looked somewhat like a tadpole. The flattened top reduced any tendency 

of the wing to generate shock waves, and the downward curve at the 

trailing edge restored the lift lost by flattening the top. Whitcomb spent 

many hours in the tunnel, hunched over development models, refining 

his concept. By 1967 he was convinced that he had a major breakthrough. 

Wind-tunnel tests indicated that the new shape would greatly improve 

the transonic performance of transport aircraft. Would the wing perform in flight as advantageously as those tests indicated? Flight validation 

was obviously required. Whitcomb and other Langley researchers started 

looking for a suitable aircraft to serve as a testbed for a supercritical wing. 

The airplane chosen was the Vought F-SA Crusader, a single-seat, 

single-engine, obsolescent Navy jet fighter. The Crusader had been an 

excellent aircraft. Capable of mach 1.7 speed and equipped with both 

cannon and missiles, it had formed the backbone of naval aviation during 

the late 1950s and early 1960s. Indeed, at the very time that NASA 

contemplated modifying an F-8A to serve as a supercritical wing testbed, advanced F-8D and F-8E Crusaders were in combat over North 

Vietnam. 

NASA selected the F-8A because it had an easily removable wing, 

which technicians could replace with a supercritical wing test installation, 

and had landing gear that retracted into the fuselage. This last meant 

that the experimental wing would not need to house the retracted 

landing gear. The F-8A was readily available from the Navy, could be 

203 
ON THE FRONTIER 

maintained with relatively little effort, and had genuine transonic 

performance. NASA acquired three of them. Whitcomb and SCW team 

members Thomas C. Kelly and Lawrence K. Loftin had decided to use 

the F-8A at a meeting on 21 March 1967. By mid-May 1968, Langley 

research director Thomas A. Toll was chairing meetings between Langley and Flight Research Center personnel to define the broad responsibilities of each center in running an F-8A SCW proof-of-concept 

dem~nstration.~ 

In February 1969, NASA announced that Whitcomb‘s supercritical 

wing concept would be tested on a modified F-8 at the Flight Research 

Center. NASA Administrator Thomas 0. Paine testified before a congressional committee that the tests would probably begin in late 1970. 

“Because of its potential for enhancing both the cruise performance and 

the operations economics of subsonic jet aircraft, this new NASA concept 

has generated widespread interest within the aircraft indu~try.”~ Whitcomb‘s 

team designed a shapely transport-type wing for the F-8 and ran tests in 

Langley’s 8-foot tunnel on a model F-8 having such a planform. Military 

applications of supercritical wing technology took a different path, that 

of the TACT program, which will be described shortly. The F-8 SCW 

program was oriented entirely toward civil aviation. Indeed, some 

observers saw the program as NASA attempting to sell the American 

aircraft industry on a concept, whereas NACA-NASA’s traditional role 

had been to conduct research, present the results at meetings and 

symposia, and let industry decide what to do. 

The Vought F-8A arrived at the Flight Research Center on 25 May 

1969. Center pilots Thomas C. McMurtry and Gary Krier began flying it 

to gain operational experience in the plane before it was modified. FRC 

contracted with North American- Rockwell’s Los Angeles Division to 

fabricate the supercritical wing, at a cost of $1.8 million. Meantime, 

North American- Rockwell “gloved” a supercritical airfoil on the wing of 

a Navy T-2C Buckeye jet trainer at the company’s Columbus, Ohio, 

plant, to gain some preliminary experience with such wings. The 

Buckeye made its first SCW flight at Columbus on 24 November 1969 

without any unusual results. Three weeks earlier, North American had 

delivered the F-8’s supercritical wing to Edwards. NASA planned the 

first trials of the aircraft in early 1971. By this time, Krier and McMurtry 

had completed 32 flights in the unmodified Crusader, which received the 

designation TF-8A.* NASA engineers set to work installing the new 

wing on the plane.5 

*Not to be confused with Vought’s abortive two-seat TF-8A Crusader (the F8U- lT), only one 

of which was completed. 

204 
A CENTER WITH DIVERSITY 

Whitcomb and his Langley team had desired as pure a wing as 

possible, so that the full spectrum of SCW performance could be 

explored without interference from gaps, flaps, or ailerons. Instead of 

ailerons on the wings for roll control, he had preferred that the F-8 be 

modified with a “rolling” tail such as was used on the X- 15, This proved 

unworkable; the rolling tail gave inadequate control at low speeds. 

Whitcomb had to accept an aileron on the supercritical wing. The 

standard Crusader had a two-position, variable-incidence wing to reduce 

its landing speed; the test wing was fixed and required a fast landing 

approach. This made the plane totally unsuited for operation from a 

conventional runway. Otherwise, Langley could have run the program 

entirely at Hampton. In fact, because the plane touched down at about 

315 kilometers per hour and lacked antiskid provisions, it could not even 

land on Edwards’ 4600-meter runway without coasting onto the overrun. 

Takeoffs were from the main runway toward the lakebed; the craft 

landed on the lake itself.6 

By early 197 1, FRC technicians had installed the shapely wing on the 

TF-8A. Tom McMurtry was the lead project pilot; engineer John 

McTigue, who had earlier shepherded the lifting bodies, was the first 

program manager. At Langley, Thomas Kelly acted as that center’s 

project engineer and Whitcomb took a personal interest in the tests. 

McMurtry and pilot Gary Krier practiced in an SCW simulator that FRC 

technicians built, and NASA modified the aircraft to incorporate artificial stability devices. On 9 March 1971, McMurtry took off on the 

TF-8A’s first supercritical wing flight. During the 50-minute excursion, 

he evaluated the plane’s low-speed handling qualities and stability 

augmentation system attaining an altitude of 3000 meters and a maximum speed of 555 kilometers per hour.’ 

The supercritical wing TF- 8A was perhaps the most graceful 

aircraft flown by NACA-NASA at Edwards. Testing went smoothly as 

NASA gradually expanded the flight envelope to higher altitudes and 

higher speeds. On its fourth flight 13 April 1971, McMurtry took the 

plane to mach 0.9 at 11 000 meters. On 26 May he reached mach 1.1 at 

11 000 meters. The first data-gathering flight came on 18 August, 

following installation of special instrumentation, including a network of 

250 pressure sensors on the wing’s upper surface to locate and measure 

shock-wave formation. Though the supercritical wing promised great 

performance improvement at about mach 0.9, engineers wanted it flown 

beyond mach 1 to see if any undesirable trim problems developed there. 

The early exploratory flights had turned up no surprises, always a 

pleasant occurrence; and tentative data indicated that the wing’s flight 

performance was close to that expected from tunnel tests at Langley. In 

fact, the program had already given sufficient encouragement for NASA 

205 
ON THE FRONTIER 

and Air Force’s Flight Dynamics Laboratory to begin another SCW 

research program, the military-oriented TACT effort.’ 

Whitcomb envisioned the ideal transonic transport as having both a 

supercritical wing and transonic area ruling-and, at a later date, winglets-so in May 1972, NASA reworked the F-8’s instrumentation and installed new fuselage fairings that gave it pronounced area ruling. It first 

flew with the fairings on 28 July 1972. By the end of the year, the research utility of the aircraft was nearing an end. Other programs demanded funding, such as the Blackbirds. Whitcomb was certainly not one 

to let a program conclude hastily; he too recognized that the F-8 effort 

had reached the point of diminishing returns. Starting in January 1973, 

FRC began flying the aircraft on pilot familiarization flights. Ron Gerdes 

had the honor of making the last flight, on 23 May 1973. As if sensing the 

end, the plane chose this flight to develop a serious problem; its prime 

hydraulic system failed, but Gerdes landed the aircraft safely on the lake. 

The plane, as attractive as ever, remains at Dryden to this day.g 

NASA wasted no time in presenting the results of the SCW F-8 

program to the rest of the government and industry in a major 

symposium at Edwards on 29 February 1972. Richard Whitcomb commented on the good correlation of flight test and ground test data. The 

SCW concept had increased the transonic efficiency of the F-8 by as 

much as 15%, and the tests showed that passenger transports with 

supercritical wings would increase profits by 2.5% over those of conventional aircraft, a total of $78 million per year (in 1974 dollars) for a 

280-plane fleet of 200-passenger airliners. Such savings in a fuel-crisis 

economy were too important to pass by. 

Industry rapidly applied the results of supercritical wing technology 

to new designs such as the Boeing and Douglas YC- 14 and YC- 15, the 

The NASA F- 8 supercritical wing (SCW) testbed. 

206 
A CENTER WITH DIVERSITY 

Rockwell Sabreliner 65, and the Canadair Challenger. France exploited 

the concept with an advanced model of the Dassault Falcon business jet. 

Indeed, foreign interest in employing SCW concepts caused NASA to 

look closely to determine if NASA-derived data was being used without 

due consideration of patent law. At NASA Headquarters on 4 June 1974, 

Administrator James C. Fletcher conferred on Whitcomb the maximum 

$25 000 prize for invention of the supercritical wing. The National 

Aeronautic Association awarded him the 1974 Wright Brothers Memorial Trophy. '' 

Before the F-8 had completed its flight program, NASA and Air 

Force interest in supercritical wing technology had spawned the TACT 

program. TACT-for Transonic Aircraft Technology-involved modifying a General Dynamics-Convair F- 11 1A to explore how SCW technology could benefit new military aircraft designs. During the 1960s, as a 

result of trying to save the lagging F-111 program, Langley Research 

Center had undertaken a great deal of wind-tunnel work on that aircraft. 

In addition to the transport-type wing tested on the F-8, Whitcomb had 

devised a supercritical wing for a transonic maneuvering military aircraft. 

The F- 11 1 was chosen as the testbed because of its variable-sweep wings. 

The new wings could be installed easily on the aircraft, with a minimum 

of other modifications. Indeed, when word of the apparent advantages 

of supercritical wing technology reached beyond Hampton, the Air Force 

Flight Dynamics Laboratory began examining the concept. General 

Dynamics engineers conceived a retrofit program for the entire F- 11 1 

fleet. The company dubbed this program F- 11 1 TIP: Transonic Improvement Program. By mid- 1970 General Dynamics had broached this 

to the Air Force. The Air Force wanted the F- 11 1 tests as a valuable 

proof-of-concept evaluation, but would not retrofit the entire fleet. By 

mid-1971 NASA and General Dynamics had expended over 1600 hours 

of wind-tunnel test time on a suitable wing for the F- 11 1. Whitcomb 

determined its shape, twist, and airfoil coordinates. General Dynamics 

built the wing, and the Air Force Flight Dynamics Laboratory furnished 

the money. On 16 June 1971 NASA and the Air Force signed a joint 

Transonic Aircraft Technology (TACT) agreement to explore the application of supercritical wing technology to maneuverable military aircraft. 

The F- 11 1 would be flown at NASA's Flight Research Center, and development of the advanced configuration of the wing would be undertaken by NASA's Ames Research Center. The TACT program, then, affected much of NASA as well as industry and the Air Force. Like the 

contemporaneous F-8 effort, TACT was far more than just a flight program. Eventually almost as much funding went to support numerous windtunnel studies as toward the actual flight program. TACT became primarily a wind-tunnel correlation program, in spite of General Dynamics' 

earlier hopes that it might spawn an SCW retrofit program for the 

207 
ON THE FRONTIER 

F- 11 1 fleet. Charles J. Cosenza of the Flight Dynamics Laboratory ran 

the Air Force TACT effort. At the Flight Research Center, NASA 

engineer Weneth D. Painter took over as NASA TACT project engineer.' ' 

The F- 11 1A was an ideal carrier for a supercritical wing. Capable of 

supersonic speeds above mach 2, the aircraft had a large volume for fuel. 

and instrumentation. The wings were easily removable. The variablesweep provision enabled SCW testing over a wide range of wing sweep 

angles and aspect ratios. Also the Air Force planned to install pylons 

under the wings to carry external stores (such as bombs and drop tanks) 

to evaluate how these shapes interfered with the supercritical flow field. 

Fortunately, an F- 11 1A was readily available: the 13th of that first 

undistinguished and unlucky bunch of F- 11 1A research and development aircraft. NASA signed a loan agreement for the airplane with the 

Air Force on 3 February 1972, and on 18 February NASA pilot Einar 

Enevoldson and Air Force pilot Maj. Stu Boyd checked out in the plane. 

The modified aircraft was ready by the fall of 1973, and on 1 November 

Enevoldson and Boyd made the first TACT flight, reaching mach 0.85 at 

8600 meters. On the 6th flight, 20 March 1974, they exceeded mach 1; 

and on the 12th flight, they reached mach 2." 

Thereafter the TACT aircraft flew frequently, with a mixed Air 

Force- NASA crew. The wing definitely improved the performance of 

the F- 1 1 l.13 At transonic speeds, the wing delayed drag rise and produced twice as much lift as the conventional F- 11 1 wing. The supercritical wing did not impair high-mach performance, either. In fact, the plane 

spent a great deal of time above mach 1.3. The external stores tests, with 

the F- 11 1 carrying drag-inducing multiple bomb shapes on the pylons, 

came off without a hitch. Fears that the external stores might wipe out 

any benefits from the supercritical planform proved without foundation. 

As with the F-8 effort, the correlation between tunnel and flight tests 

proved close. In November 1975 NASA and the Air Force sent TACT 

program personnel from Edwards, the Flight Research Center, the Flight 

Dynamics Laboratory, Ames Research Center, and Langley Research 

Center around the country to brief industry and government representatives. 

The message was simple: TACT, like the earlier SCW F-8 program, had 

been an unqualified success. Test results were readily available for the 

use of industry in developing new and advanced military aircraft.14 

The F- 11 1 TACT aircraft soon became a workhorse, flying with a 

variety of aerodynamic experiments, including special shapes to evaluate 

base drag around the tail, experimental test instrumentation, and equipment destined for use with other airplanes. It was still flying in 1980, 

seven years after its first SCW exploration, the most productive of all the 

early F-11lA test aircraft. The TACT experience encouraged the Air 

Force Flight Dynamics Laboratory to proceed with another research 

effort: Advanced Fighter Technology Integration (AFTI). Another joint 

208 
A CENTER WITH DIVERSITY 

NASA3 modified F-lllA transonic aircraft technology (TACT) testbed, equipped with a 

Whitcomb supercritical wing, descends for a landing at Rogers Dry Lake. 

Air Force-NASA effort, it consisted of various “Technology Sets.” AFTI 

Tech Set I1 was a direct extension of the TACT program. Like TACT, 

the AFTI program involved the F- 1 1 l-in fact, the Flight Dynamics 

Laboratory examined no less than six different F- 11 1 testbed configurations. This TACT “second phase,” subsequently called AFTI- 1 1 1, 

went a step further, with conceptualization of a “mission adaptive wing.” 

This wing would not have the surface irregularities produced by conventional high-lift devices such as flaps and leading edge slats. Instead, an 

internal mechanism would flex the outer wing skin to produce a highcamber airfoil section for subsonic speeds, a supercritical section for transonic speeds, and a symmetrical section for supersonic speeds- hence 

the name “mission adaptive.” The TACT F- 11 1 modified as this AFTI 

demonstrator was scheduled to fly at Edwards in 1984. An F- 1 1 1 testbed 

with this wing might eventually have other novelties as well, such as an 

advanced composite wing structure, a two-dimensional exhaust nozzle, 

coupled propulsion and flight controls, and “active” flight controls. Such 

a technology demonstrator can be expected to fly in the mid-1980s. When 

it does, it will be the heir to the earlier work undertaken at Edwards with 

the F-8 and the TACT F-lll.15 

By the beginning of the 1980s, a growing number of transonic and 

high-subsonic aircraft were flying with supercritical wing planforms. There 

could be no greater tribute to NASA research, and particularly the work 

of Richard Whitcomb. A similar situation had happened in the 1950s, 

when his area rule concept quickly became de rigueur for advanced aircraft; 

it may happen yet again, when the full benefits of the Whitcomb winglet 

209 
9 

ON THE FRONTIER 

are realized, following flight testing at Dryden of the winglet concept on a 

modified Air Force KC- 135. During the 1950s, the High-speed Flight 

Station had played an important role in validating the area rule. During 

the 1970s, the center played an equally important role in validating the 

supercritical wing. Through the efforts of the center, the new, exciting 

shape of the supercritical wing took its place in the sky. 

RADIO-CONTROLLED RESEARCH 

Remotely controlled aircraft appeared as early as World War I; by 

the end of World War 11, the major powers had made extensive use of 

remotely controlled guided weapons. The technology obviously had 

great potential; during the 1950s, remotely controlled Regulus and 

X-10 missile testbeds were landed on the lake at Edwards. At the same 

time, flying radio-controlled model airplanes became a widespread (if 

expensive) hobby. Electronic advances in the mid- 1960s greatly increased 

the reliability of control systems as tubes gave way to solid-state components. 

It took the insight of FRC engineer Dale Reed to blend this weekend 

hobby with a professional interest in aeronautical development; the 

result was a new method of flight testing, using remotely piloted research 

vehicles (RPRVs) . The RPRV concept differed appreciably from previous “drone” or 

remotely piloted vehicles (RPVs). A limited autopilot had controlled 

those craft through a restricted number of maneuvers. Some RPVs could 

be used for military purposes, such as reconnaissance or remotely 

controlled strike missions. Drones were used extensively in the Vietnam 

War and during the 1973 Middle East war. The RPRV, on the other 

hand, eventually emerged as a study tool capable of versatile applications 

and of operating in “unexplored engineering territory.”16 

In support of the M2 lifting body program in the early 1960s, Dale 

Reed built a number of little lifting body shapes and launched them from a 

twin-engine radio-controlled model called Mother that spanned 3.2 meters. 

By late 1968, Mother had made over 120 launch drops. The move to more 

sophisticated equipment came in late 1968. Following the loss of the 

X-15 and Mike Adams, FRC installed an X-15-type “8-ball” attitude 

indicator on a TV monitor in the control room. One day, while test pilot 

Milt Thompson and engineer Reed were monitoring a flight, Reed asked 

the pilot if he could control an actual research airplane by using the 8-ball 

as a reference. Thompson averred that he could. Within a month, at a 

cost of $500, Thompson was flying Mother from the ground by reference 

to the instrument. Next, Reed wanted to see if a pilot could get the same 

results flying a full-scale research airplane. Because of his interest in 

lifting body reentry vehicles, Reed selected the Langley Hyper 111 

210 
9 c 

A CENTER WITH DIVERSITY 

configuration, a very slender reentry shape having a flat bottom and flat 

sides. The Hyper I11 shape had a lift-to-drag ratio of about 3, and Reed 

designed it with a fixed wing simulating a “pop-out” wing such as could 

be used to improve the low-speed glide ratio of an actual reentry vehicle. 

Shop personnel built the vehicle at a cost of $6500. The RPRV weighed 

220 kilograms, measured 9.7 meters in length, and spanned 5.6 meters. 

By December 1969 the center was ready for the initial trials. Hyper 111 

was launched from a helicopter at 3000 meters, glided five kilometers, 

reversed course, and glided five kilometers to touchdown. As the Hyper 

I11 came in for a landing, Thompson transferred control to an experienced model-flyer who used standard controls to flare the lifting body 

and fly it to touchdown. The craft rolled along the lake, just like any 

of the other exotic research aircraft at Edwards.” 

Thompson exhibited some surprising reactions during the Hyper 

I11 flight; he behaved as if he were in the cockpit of an actual research 

aircraft. “I was really stimulated emotionally and physically in exactly the 

same manner that I have been during actual first flights,” Thompson 

recalled afterwards. 

Flying the Hyper I11 from a ground cockpit was just as dramatic as an 

actual flight in any of the other [full-scale manned] vehicles. , . . I, and 

only I, had to fly the vehicle down to a preselected location for 

landing. . . . responsibility rather than fear of personal safety is the 

real emotion driver. I have never come out of a simulator emotionally 

and physically tired as is often the case after a test flight in a research 

aircraft. I was emotionally and physically tired after a 3-minute flight 

of the Hyper 111.” 

Although encouraged by the Hyper 111 experience, FRC did not test I 

that shape further since it had a much lower lift-to-drag ratio than 

predicted. Many other programs-other lifting bodies, the YF- 12 

Blackbirds, and the SCW F-8-had a more urgent call on the center’s 

time and manpower. Reed and his RPRV team decided to try to control 

an actual manned aircraft by means of a ground pilot, with a back-up 

pilot in the plane. The center selected a Piper PA-30 Twin Comanche, a 

light, twin-engine airplane already configured as a testbed for generalaviation flight controls. As flown by FRC, the Twin Comanche had dual 

controls, one side an electronic fly-by-wire system, the other a conventional system, permitting controls research. That arrangement made the 

aircraft particularly well suited for RPRV research. FRC already had 

“downlink” electronics-such as pulsecode modulation telemeteringsupported by the center’s radar tracking and digital computing equipment. 

The “uplink” electronics carrying the radio commands to the RPRV came 

from military research with drones. A forward-pointing television system 

21 1 
ON THE FRONTIER 

The Hyper III remotely piloted research vehicle (RPRV)Jlew at the Flight Research Center 

in December 1969. 

in the RPRV transmitted images from the aircraft to a ground cockpit, 

where the operating pilot flew the aircraft by reference to the visual cues. 

To provide physical cues as well, technicians connected small electronic 

motors to straps around the pilot’s body. During sideslips and stalls, the 

straps exerted forces on the pilot in proportion to the lateral accelerations being telemetered from the RPRV. The forces on the pilot made it 

feel natural for him to push rudder pedals to control sideslip. 

In October 1971, FRC began flight trials, with center pilot Einar 

Enevoldson flying the PA-30 from the ground as FRC pilot Tom 

McMurtry rode as safety pilot. Eventually, Enevoldson flew the airplane 

unassisted from takeoff through landing, making precise instrumentlanding-system approaches, stalls, and stall recoveries. ’’ 

The next step was applying the RPRV to some meaningful research 

project. In April 1971 Grant Hansen, assistant secretary of the Air Force 

for research and development, issued a memorandum calling for a 

national program to investigate stall and spin phenomena. This area had 

become critical; many fighter aircraft were being lost in spinning 

accidents. The Air Force’s Aeronautical Systems Division formed a 

steering committee that included NASA representatives; it recommended 

expanding existing programs using radio-controlled free-flight models 

to evaluate spin entry and post-stall gyrations. Langley Research Center 

had made stall-s pin studies using small-scale models dropped from 

2 12 
c P a 

A CENTER WITH DIVERSITY 

The Flight Research Center’s Piper Twin Comanche, which helped validate the RPRV 

concept, descends to a remotely controlled landing on Rogers Dly Lake, unassisted by the 

mboard pilot. 

helicopters, but the committee recommended using larger models. Scale 

effects, always significant in model testing, were especially important in 

stall-spin tests; it was important to verify or refute the Langley tests by 

examining the results of tests with larger models. 

Over the spring and summer of 1971, Reed and other FRC engineers studied the feasibility of stall-spin testing an RPRV model. One 

advanced Air Force fighter project then under way could benefit from 

such work-the McDonnell F- 15A Eagle, a mach 2 highly maneuverable 

dogfighter designed using lessons from air combat over North Vietnam. 

Maj. Gen. Benjamin Bellis, chief of the F-15 System Project Office at 

Wright-Patterson, wanted the Flight Research Center to test an RPRV 

modeled after the proposed Eagle. In November 1971 the Flight 

Research Center transmitted a proposal to NASA Headquarters for stalland spin-testing a 318 scale model of the F-15 configuration; OAST’s 

Military Programs Office quickly assented. In April 1972 NASA awarded 

the McDonnell Douglas Aircraft Corporation a $762 000 contract for the 

construction of three 3/8 scale F- 15 models. NASA placed a variety of 

contracts with other firms for supporting equipment including electronic 

components and parachute recovery equipment.20 

The first F-15 RPRV arrived at the Flight Research Center on 4 

December 1972. The 1100-kilogram vehicle, 7.3 meters long, was fabricated from aluminum, hard and soft woods, and fiber glass. It cost a 

little over $250 000, compared to $6.8 million for full-scale, piloted F- 15 

aircraft. McDonnell Douglas built the vehicles, and the Flight Research 

Center added the avionics, hydraulics, and other subsystems. 

213 
ON THE FRONTIER 

The F-15 RPRV was launched from a B-52 mothership at about 

15 000 meters, after which an FRC pilot put the aircraft through its 

planned research program. Upon reaching 5000 meters, the RPRV 

streamed a spin recovery parachute having a diameter of 4 meters; that 

chute then extracted two other parachutes, an 8-meter “engagement 

chute” and a 24-meter-diameter main chute. As the F-15 RPRV 

descended, a helicopter snagged the engagement chute with grappling 

hooks. After a complex series of events, the main chute separated from 

the F- 15, and the helicopter reeled in the RPRV with a winch, until the 

research vehicle was suspended about 5 meters below the helicopter. The 

helicopter then returned to the Flight Research Center. Should it be 

impossible to recover the F-15 from a spin or stall, the pilot on the 

ground could deploy the spin recovery chute early, initiating the recovery sequence. Similar airborne snatch recoveries were already standard 

operating procedure for drone aircraft such as the Ryan Firebee. 

Eventually, NASA planned to land the F- 15 RPRV on the lakebed using 

skids, like any other research airplane.21 

On 12 October 1973 the first F- 15 RPRV went aloft under its B-52 

mothership for a flawless nine-minute flight, remotely piloted by Einar 

Enevoldson. He found the task challenging; researchers monitoring his 

heart rate found it went from a normal 70-80 beats per minute for a 

manned flight test to 130- 140 for the first RPRV flight.22 

Subsequent testing confirmed the ability of the RPRV to return 

useful information. McDonnell Douglas and the Air Force were encouraged to proceed with manned spinning trials in the actual F- 15 Eagle. 

The only serious incident in the F-15 RPRV program occurred after 

pilot Tom McMurtry had flown the aircraft down to parachute deployment, 

and the helicopter had snagged the parachute. About 1000 meters above 

the ground, the lines separated, and the F- 15 model was once again in 

free flight. McMurtry quickly assumed control and guided the plane to 

an emergency landing in the desert. The plane hit a Joshua tree and a 

raised roadbank, inflicting some damage-but McMurtry’s skill had 

saved it to fly another day. The incident encouraged those who wished to 

land the RPRVs using skids. Soon after, NASA did indeed begin landing 

the F-15 RPRV on the lake, like any other unpowered research 

airplane.23 

Controversy still surrounds the RPRV concept. Ground researchers 

have sometimes tended to see the method as a way of relegating manned 

flight testing to a position of unimportance. More dispassionate champions of the concept recognize that the RPRV complements-but cannot 

replace-manned flight testing. RPRVs are ideal for use when manned 

testing is impossible or unduly dangerous. In some situations, they can be 

considerably cheaper than testing a manned aircraft. But they cannot 

match the flexibility of a manned research airplane; in the words of one 

2 14 
A CENTER WITH DIVERSITY 

An F- 15 RPRV is carried to launch altitude by a B-52 mothership. 

Dryden airman, they are “damn limited.” They cannot fly independently 

of a large, complex ground support system, so support costs for RPRV 

vehicles closely approximate those of manned aircraft. Nevertheless, the 

Flight Research Center had proved that the RPRV could make a 

meaningful contribution to flight research. 24 

Dryden has continued its work with RPRVs since the F- 15 RPRV 

program. In cooperation with Robert Jones and the Ames Research 

Center, Dryden engineers flew a propeller-driven RPRV having a Jones 

oblique swingwing. Center engineers have also flown an air-launched 

Ryan Firebee I1 in support of advanced RPRV projects. The most 

ambitious of Dryden’s RPRV efforts is the Rockwell-NASA HiMAT. 

HiMAT-for Highly Maneuverable Aircraft Technology-is a powered 

RPRV using an afterburning General Electric 585-2 1 turbojet engine. It 

has a wingspan of over 5 meters and a length of over 7 meters. Designed 

215 
ON THE FRONTIER 

as a technology demonstrator, the HiMAT aircraft is a sharply sweptwing 

canard configuration that should provide the technology base necessary 

for an advanced 1990 fighter system. HiMAT features a composite 

structure of glass fibers, graphite composites, and various metals. Following two preliminary study phases, in August 1975 NASA awarded 

Rockwell International a $1 1.9-million contract for two HiMAT aircraft, 

the first of which was completed in mid-19’78. After launch from a B-52 

mothership, the HiMAT vehicle is flown through a complex series of 

maneuvers at transonic speeds by a NASA pilot at Dryden’s RPRV 

remote pilot control facility. Then he lands it on Rogers lakebed. A chase 

airplane provides emergency backup control. While HiMAT is Dryden’s 

major RPRV research effort for the first half of the 1980s, Dryden is also 

running another RPRV project, Mini-Sniffer, begun in 1975. This is an 

attempt to develop a propeller-driven RPRV operating on hydrazine 

monopropellant fuel to altitudes around 30 000 meters to gather air 

samples from the wakes of high-flying supersonic aircraft. Three MiniSniffer configurations have been built. The concept has led to interest by 

various research facilities, including the Jet Propulsion Laboratory, in 

using similar vehicles for planetary sampling missions. Such an aircraft 

could be used on Mars as part of a planetary probe. Clearly, Dryden’s 

RPRV work has been and will continue to be an important aspect of the 

center’s-and NASA’s-re~earch.~~ 

ELECTRONIC CONTROLS 

In the early days of aviation, pilots controlled their aircraft by direct 

force. They moved a stick or pushed a rudder pedal connected to cables 

that, in turn, pivoted a control surface. In those days an on-off switch 

provided full engine power or none at all. In time, sets of throttles and 

fuel mixture controls regulated engine power. As flight speeds rose, 

control loads increased, eventually reaching a point where pilots could no 

longer exert sufficient brute strength to control airplanes at high speeds. 

The next step was hydraulically boosted controls. Control systems now 

became complex indeed. By the early 1960s, jet aircraft were operating 

with boosted hydro-mechanical controls. These were very vulnerable to 

damage; loss of hydraulic pressure in the control system could spell the 

end of an airplane even if all other systems functioned smoothly. The 

necessity for redundant backup systems further complicated aircraft 

design, while design constraints often minimized the benefit of these 

backup systems. For example, the Air Force lost many Republic F- 105 

Thunderchief aircraft over North Vietnam to antiaircraft fire that 

damaged the craft’s hydraulics. “Unfortunately,” one “Thud” driver has 

written, “a hit that caused loss of one flight control hydraulic system 

2 16 
A CENTER WiTH DIVERSITY 

usually got them both.”26 In another case, Grumman lost the first 

prototype F-14 Tomcat on its maiden flight as a result of hydraulic 

failure, an accident that delayed the program at a critical time. 

Conventional hydraulic-mechanical control systems also imposed 

design limitations upon aircraft configuration. Designers had to incorporate a degree of inherent stability even if the plane had stayiity 

augmentation; during some portions of the flight the pilot could not be 

continuously moving the controls. But the aircraft could not be allowed 

to go out of control during those moments. Designers therefore had to 

use tail surfaces of a certain size and in a certain location; the wing had to 

be located in a certain position; the fuselage had to be of a certain length. 

But with electronic controls, in which the pilot’s commands go to a digital 

computer, which sends a signal flashing through a wire to move the 

controls electronically, all this could be changed. Electronic “fly-by-wire” 

controls are much less vulnerable to damage than conventional hydromechanical controls; several wire bundles can be routed through an 

aircraft with greater flexibility than a maze of pushrods, pulleys, and 

cables. Electronic controls also are simpler, smaller, and lighter, advantages that translate directly into improved performance, reliability, 

payload, and fuel consumption. A fly-by-wire control system could 

revolutionize the way an airplane looks. No longer will designers have to 

tailor their configurations a certain way. The electronic controls could 

provide aircraft stability; a sensing unit could detect any tendency of the 

aircraft to diverge from its desired flight path and warn the digital 

computer to signal corrective control deflection. When the pilot made a 

control input, it would in fact be a command to the system to “relax” the 

stability briefly so that the aircraft would move in the direction the pilot 

wished to go. With the electronic control system furnishing stability, 

designers could reduce the size of some components, such as tail surfaces, 

or even relocate them. Such changes could reduce the size and weight of 

aircraft, lessen drag, and permit increases in payload and performance. 

The primary, and immediate, advantages are in simplicity and maneuverability. “Control configured vehicles” (CCV) promise to have outstanding 

maneuvering characteristics. Indeed, with fly-by-wire controls, aircraft 

could perform such maneuvers as intentional and prolonged yawed 

flight, with obvious advantages for military airplanes. 

First, however, the fly-by-wire principle had to be proved. Some 

earlier aircraft had used rudimentary fly-by-wire controls. The Concorde 

SST used a pseudo fly-by-wire system for primary flight control, but the 

secondary system was conventional hydromechanical. At the Flight 

Research Center, engineers desired a true fly-by-wire testbed having 

strictly electronic controls. They discussed radically reconfiguring a 

conventional fighter, such as the Lockheed F-104 or a Vought F-8, 

217 
ii f c 

ON THE FRONTIER 

with fly-by-wire controls and revised flight control surfaces, perhaps 

reducing tail size or incorporating a canard layout. Engineer Melvin 

Burke was especially interested in flying a digital fly-by-wire testbed. 

Considering how important the technology has subsequently become, 

NASA Headquarters expressed little interest in the idea until Neil 

Armstrong became NASA’s deputy associate administrator for aeronau-’ 

tics within the Office of Advanced Research and Technology. During the 

Apollo program, he had become acquainted with fly-by-wire technology 

at the controls of the lunar module. That vehicle had a digital computer 

and inertial measuring unit. When the astronaut moved his controls, the 

computer sent signals to reaction controls that maneuvered the vehicle. 

Armstrong believed this off-the-shelf system could be readily applied to a 

testbed airplane and supported Burke’s project. With OART’s approval, 

the Flight Research Center acquired a Navy Vought F-8C Crusader, 

disconnected its mechanical flight control system, including all cables, 

push rods, and bell cranks, and replaced it with the Apollo-derived 

digital flight computer and inertial sensing unit, routing sets of wire 

bundles from the pilot’s control stick to the computer, and thence to the 

control surfaces. This marked the beginning of FRCTJ F-8 Digital Flyby-Wire (DFB W) flight research pr~gram.~’ Massachusetts Institute of 

Technology’s Charles Stark Draper Laboratory supported FRC’s effort 

by reprogramming the Raytheon computer from the lunar module. 

Sperry’s Flight Systems Division supplied a backup fly-by-wire system for 

the aircraft. 

On 25 May 1972 center research pilot Gary Krier completed the first 

flight of the F-8 DFBW testbed, the first flight of an airplane completely 

dependent upon an electronic control system. Using off-the-shelf equipment had enabled NASA to make that flight at least two years earlier 

than would have been the case starting from scratch. The agency 

awarded the DFBW project team its Group Achievement Award during 

Headquarters ceremonies in November 1972. By early 1973, after 15 

DFBW flights without incident, Kries testified before the House Committee on Science and Astronautics on the benefits the program had already 

demonstrated. Clearly fly-by-wire equipped transport aircraft could fly 

with greater smoothness in turbulence-the near-instantaneous sensing 

of motion changes, combined with an immediate computer-signaled 

corrective control response, would rapidly damp any turbulence-induced 

aircraft motions. “A much larger improvement in performance could be 

gained by starting from scratch with FBW,” Krier testified. “We have 

been refining aircraft for years now, and the FBWICCV combination 

gives us a chance to make a quantum jump in aircraft performan~e.”~~ 

Like all trial systems, the F-8’s DFBW installation did have some 

operational quirks. The electronic interface on the Apollo computer was 

too coarse for the precise pilot stick inputs required to fly the plane. The 

218 
c 

A CENTER WITH DIVERSITY 

Piloted by Gary Krier, the NASA F- 8 digitalfly-by-wire (DFBW) testbed cruises on a 

research mission from Rogers Dry Lake. 

computer changed control-surface positions in a series of steps, like the 

small but abrupt movements of a watch’s second hand. The pilot felt this 

as a mild but unpleasant series of nudges, especially when using the 

all-moving horizontal stabilizer for pitch control. At FRC‘s request, the 

Draper Laboratory changed the computer software, with beneficial 

results to the handling qualities of the plane. The F-8 flew 42 times 

without incident and it was never necessary to resort to the plane’s 

emergency back-up flight control system. Before finishing the test 

program, a prototype version of the electronic sidestick planned for the 

General Dynamics F- 16 fighter was tested on the F-8, including 

formation flight and landings. The results lent encouragement to the 

practicality of using such a stick on the F- 16 itself. 

The first phase of the F-8 program had only shown that DFBW 

control was feasible, not that it was practical. The system used much 

special purpose hardware and, although it was extremely reliable, it could 

not operate if the digital computer failed. In a joint program with the 

Langley Research Center, Dryden received funding to develop and 

flight-test an advanced redundant digital fly-by-wire system in place of 

the modified Apollo system. This “triplex” DFBW system used generalpurpose digital computers and would be able to sustain several system 

failures and still operate. It was flown in August 1976, with a ridesmoothing system, maneuver-driven flaps,” and an angle-of-attack limiter. 

These are typical of the characteristics expected on future vehicles 

employing DFBW control. The F-8 system also demonstrated “fault- 

*Sensors detect vehicle maneuvers, triggering appropriate flap movement to enhance airplane 

performance during the maneuver. 

219 
ON THE FRONTIER 

tolerance” by continuing normal operation after certain computer failures. 

After the initial development flights, the F-8 was used to test Shuttle 

computer software and to support the development of the flight control 

system of the Shuttle orbiter.ZY 

Dryden’s Digital Fly-by-Wire flight research program is only one of 

the electronic control programs that will continue to influence the 

development of this new technology. Another is the center’s Integrated 

Propulsion Control System (IPCS) evaluated on an Air Force F-111E 

airplane. This program, run from March 1973 through February 1976, 

involved a cooperative effort by NASA’s Lewis and Flight Research 

Centers, the Air Force’s Flight Propulsion Laboratory, and the Boeing, 

Honeywell, and Pratt 8c Whitney companies. In essence, it accomplished 

for the propulsion system of an airplane what fly-by-wire controls did for 

flight control. Numerous factors affect engine performance, including 

throttle position, inlet position for variable-geometry inlets, fuel flow 

rates, and even the maneuvers that an aircraft is performing at any 

particular time. As with mechanical aerodynamic controls, the hydromechanical controls used in engine operation grew increasingly complex. 

Propulsion experts at NASA’s Lewis Research Center recognized that 

future aircraft might demand propulsion control systems capable of 

controlling a number of variables with much greater accuracy and speed. 

Digital electronic controls might well provide the answer. 

The Air Force Flight Propulsion Laboratory at Wright-Patterson 

AFB was willing to fund an experimental effort using a suitable airplane. 

A twin-engine airplane could be configured so that one engine was 

electronically controlled. The other engine could remain hydromechanically 

controlled for flight safety and to provide a comparison with the test 

engine. One aircraft immediately came to mind-the General Dynamics 

F- I1 1. The F- 1 I 1 was a large, two-seat twin-engine aircraft with a 

complex propulsion system. It had a variable position inlet and afterburning 

fanjet engines, as well as an internal weapons bay that researchers could 

use to house the necessary electronic controls. The Air Force had an 

F- 1 11 available, the first prototype of the General Dynamics F- 11 1E 

series. Lewis and the Air Force selected Boeing as prime contractor to 

develop the system, with Honeywell and Pratt 8c Whitney as subcontractors. NASA awarded the contracts for the Integrated Propulsion 

Control System program in March 1973. 

The program could have been run at Lewis; but for various reasons, 

including flight safety, NASA and the Air Force decided to fly the 

F- 11 1E IPCS testbed from Flight Research Center at Edwards. Once 

FRC became involved, center personnel did far more than just fly and 

maintain the airplanes. Indeed, FRC engineers and pilots initially resented what they saw as an effort by various distant parties to dictate what 

was to be done, how, and when. “It took a year before we really 

220 
A CENTER WITH DIVERSITY 

developed a good working relationship with everybody,” one Dryden 

participant recalled, “so that they trusted us, and we trusted them. And 

they realized we weren’t just being hard to get along with when we 

wanted changes or said we had a problem. They started believing us.”30 

After this initial wariness, the program moved along smoothly. 

The Flight Research Center received the F-111E in mid-1974 and 

embarked on a series of 13 flights before modification. These flights 

acquired baseline data for comparison with results of the later IPCS tests. 

Installation of IPCS began in March 1975. The system consisted of an 

instrumentation package, power supply, digital computer, and interface 

equipment installed in the fuselage weapons bay. The hydromechanical 

inlet and afterburner controls were replaced by new electronic controls. 

Two software programs supported the IPCS evaluation. One of 

these was a digital representation of a TF30-P-9 afterburning turbofan 

engine used for assessing the ability of the IPCS system to duplicate the 

hydromechanical control functions. The other, called the IPCS control 

mode, integrated the inlet and engine control functions into one operation, 

exploring the new control concept. All the software and related IPCS 

control hardware were rigorously bench-tested, installed on a Pratt & 

Whitney TF30-P-9 engine and run on a test stand, and then the 

modified engine was installed in the altitude test chamber of NASA’s 

Lewis Research Center, where engineers ran the engine under planned 

flight conditions. NASA was especially interested in operation of the 

IPCSon high-altitude, low-mach flights (typically mach0.9 at 13 700 meters 

or mach 1.4 at 15 000 meters) and flights above mach 1.9, where the 

interactions of variable inlet and engine were of critical importance. 

NASA had hoped to use the actual IPCS-modified engine tested at 

Lewis, but this did not prove possible. Instead, another TF30-P-9 was 

installed. The IPCS controlled only the F- 1 11E’s left engine. Hydromechanical control was available over the left engine for emergency use, and 

the right engine retained its own hydromechanical system. As a precaution, 

however, in the event of failure of the manually controlled engine during 

takeoff and the possibility of simultaneous problems with the experimental IPCS, all takeoffs were made toward Rogers Dry Lake, where an 

emergency landing could be made.” 

The F- 11 1E completed its first IPCS flight on 4 September 1975 

piloted by NASA’s Gary Krier and the Air Force’s Stan Boyd.* It 

completed further 14 IPCS investigations before the program concluded, 

making its last IPCS flight on 27 February 1976. NASA returned the 

*Not to be confused with Stu Boyd, another Air Force test pilot who by this time had left 

Edwards. 

22 1 
ON THE FRONTIER 

F- 11 1E to the Air Force; restored to its original non-IPCS configuration, 

it served as a chase aircraft for the B- 1 strategic bomber. 

The IPCS flights demonstrated that the system worked well. The test 

crews used rapid throttle manipulation, abrupt aircraft maneuvers-such 

as high-angle-of-attack turns and sideslips-and various inlet positions to 

evaluate performance of the IPCS. Because it was not an ideal, best-of-allpossible-worlds system, the gains realized were not spectacular. But at its 

worst, the IPCS system never performed less efficiently than the hydromechanical system. This alone was significant; it indicated that, in the 

future, IPCS technology could be expected to produce major benefits. 

There were other less visible advantages. Engineers compensated for 

deficiencies in the hardware used on the IPCS by changing software 

routines. The project team noted: 

This allowed temporary corrections to be made and verified without the need 

for extensive design modifications and hardware testing that could have 

affected the flight scheduling. With this flexibility, the testing and optimization of propulsion systems can be completed without the major hardware 

modifications that accompany development in hydromechanical systems.3z 

The conclusion of the IPCS program was influenced as much by 

monetary considerations as by the fact that the system had proved its 

potential value. Dryden’s interest in electronic controls has continued, 

however, with the similar but more advanced digital electronic engine 

controls (DEEC) research program using a center F- 15. The advanced 

aircraft of the 1990s will fly with Dryden-pioneered developments such 

as digital fly-by-wire flight controls and some advanced form of IPCS. 

Some may have so-called “co-op” controls, whereby a digital system integrates flight controls and engine controls into a single efficient system. 

This too was pioneered by Dryden in May 1978, aboard the YF-12C 

B1ackbi1-d.~~ As with the supersonic breakthrough and the dawn of hypersonic flight, Dryden’s work on electronic controls will have continuing 

impact in the years to come. 

NEW CONCERNS IN AVIATION SAFETY 

The old NACA did relatively little work in the field of aviation 

safety-although some of its aerodynamics research had a serendipitous 

effect on safety. The High-speed Flight Station undertook virtually no 

aviation safety projects related to air transportation, the closest being the 

KC- 135 studies supporting the introduction of the 707-generation 

jetliners into service. Lewis Laboratory had deliberately destroyed surplus military airplanes to study how crash fires propagated. But for the 

most part, NACA had left aviation safety to the Civil Aeronautics 

Administration (the forerunner of the Federal Aviation Agency, later the 

222 
Y 

A CENTER WITH DIVERSITY 

Federal Aviation Administration), and such organizations as the Flight 

Safety Foundation and the Cornell-Guggenheim Aviation Safety Center. 

All this changed in the 1960s and early 1970s. The disconcerting 

number of general-aviation stall-spin accidents caused NASA to undertake special studies of the spinning characteristics of such aircraft. The 

agency complemented this work with other studies on the handling 

qualities of private aircraft. Much of this work was done at Langley, but 

the Flight Research Center ran a number of flight evaluations on 

general-aviation airplanes from 1964 through 1966, following these with 

tests of the center’s workhorse Piper PA-30 Twin Comanche. During 

one test flight of the PA-30, center research pilot Fred Hake encountered severe flutter of the craft’s horizontal tail while well within the 

aircraft operational limits. This dangerous situation fortunately did not 

cause loss of the tail and Haise landed safely. A film taken from a chase 

plane shows the horizontal tail twisting through an alarming arc for what 

seems an incredibly long time, evidence that the unexpected dangers in 

flight testing are not limited to high-performance jets and rocket planes. 

Though general aviation was a major research concern, two other 

problems drew particular attention: wake vortex and clear air turbulence. 

In 1907, British aerodynamicist F. W. Lanchester postulated the concept 

of the tip vortex, a “horizontal tornado,” as it were, formed by the flow 

field around a wing.34 This whirling column streams around the wing tip 

and trails in a wake behind the aircraft. Sometimes, under the proper 

conditions of humidity and temperature, the vortex can be seen. It is 

easily demonstrable in a wind tunnel or water tank, using injected smoke 

The Flight Research Center? Aero-Commander, used for liaison and a variety of generalaviation studies. 

223 
ON THE FRONTIER 

or dyes. As seen from behind the aircraft, one vortex streams from the 

right wingtip, rotating counter-clockwise. The vortex from the left 

wingtip rotates clockwise. These turbulent vortices trailing behind an 

airplane can affect other aircraft that pass through them. The magnitude 

of the vortices is directly related to the size and weight of the airplane that 

generates them: the wake vortex of a light plane such as a Cessna 150 is 

negligible, while that of a 747 can exceed 240 kilometers per hour in 

rotational velocity and can persist for a distance of 30 kilometers. The 

vortex of a large transport can easily upset a much smaller aircraft, 

possibly inducing structural failure or, more likely, throwing it out of 

control. If this occurs close to the ground-during a climbout after 

takeoff or during a landing approach-the plane might crash. Indeed, 

many aircraft have been lost in such accidents. 

The problems engendered by wake vortices first became a serious 

concern following the introduction of large jetliners. When the widebody jumbojets (the Boeing 747, McDonnell Douglas DC- 10, and Lockheed 

L- 101 1) entered service, wake vortices became a major hazard. These 

aircraft trailed vortices powerful enough to roll business jets and even 

other airliners. Further, their vortices could persist even at high altitudes. 

In response, the FAA increased minimum separation distances for 

airplanes from 5 kilometers for a small business jet following a widebody jumbojet to 10 kilometers. Even another wide-body could not follow 

closer than six kilometers behind a wide-body aircraft. These separation 

distances automatically reduced the number of aircraft that could land at 

an airport in a given time. The FAA undertook the development of 

sensors that could detect the resence of hazardous vortices in the apAnother method was to attempt to reduce the magnitude of tip 

vortices. Here is where the Flight Research Center became involved. 

NASA became interested in vortex research both from the safety aspect 

and as a matter of aerodynamics. A wingtip vortex seriously reduces 

efficiency, causing drag to rise with a consequent penalty in fuel 

consumption and performance. If the wake could be minimized, this 

could greatly increase the aerodynamic efficiency of the plane and 

improve its operating economics, always a vital concern in air transport. 

This desire for efficiency prompted Richard Whitcomb at Langley 

Research Center to develop the winglet concept: small, nearly vertical 

wing-like surfaces mounted on the wingtips of an airplane. These 

winglets reduced induced drag by 4 to 5%, offering fuel savings for a 

707-class transport of about 7%. The Dryden center subsequently tested 

a Boeing KC- 135 equipped with winglets in a proof-of-concept 

demonstration. Ames Research Center engineers experimented with 

small fins mounted above or below a wing. These fins would generate 

“good” vortices to breakup and disperse the dangerous ones. Langley 

proach corridor of an airport. !5 

224 
A CENTER WITH DIVERSITY 

Research Center engineers experimented with a nearer-term solution, 

deploying an aircraft’s spoilers and speed brakes to minimize wake vortex 

formation. Langley tunnel-tested a 311 00-scale model of a 747. Following 

up on the Langley work, the Flight Research Center flew a 747 on wake 

vortex alleviation studies.36 

The Flight Research Center had studied wake vortices with a Boeing 

727 in November 1973, equipping the plane with smoke generators to 

trace the patterns and following it with instrumented PA-30 and F- 104 

chase aircraft to measure the force and effects.” The 727 was a small 

three-engine jetliner, not comparable even to the 707, let alone to jumbo 

wide-bodies such as the 747. Fortunately, NASA bought a Boeing 

747- 100 jetliner from American Airlines for use as the Rockwell Space 

Shuttle’s carrier aircraft during the Shuttle’s approach and landing tests. 

FRC petitioned NASA Headquarters for use of this aircraft, assigned to 

the Johnson Space Center. On 16 August 1974 Headquarters assented to 

FRC’s request, and the 747 made some 30 flights in a wake vortex 

research program. Test crews varied the positions of the spoilers and 

used various spoiler segments in an attempt to determine the optimum 

method of alleviating wake vortices. Chase aircraft, including a Gates 

Learjet and a Cessna T-37 trainer (representative of business jets and 

smaller aircraft) probed the vortices to measure their strength. The 

results were surprising.38 

During one test when the 747 crew did not attempt to alleviate the 

wake vortices by spoiler operation, the T-37 entered a vortex six kiloNASA’s Boeing 747, used on wake vortex alleviation studies, is followed by a Gates Learjet 

(left) and Cessna T-37 that penetrate the 747’s wake to analyze its turbulence and 

strength. 

225 
6 n 

ON THE FRONTIER 

meters behind the 747, did two inverted snap-rolls, and developed a roll 

rate of 200 degrees per second. During another flight, the disturbed 

vortex flow caused one of the T-37’s engines to flame out. With the 747 

in landing configuration, landing gear and flaps down, the T-37 pilot 

believed that at least a 16-kilometer separation was desirable between the 

T-37 and the 747. Spoiler operation, however, markedly improved the 

situation. With two spoilers on the outer panels of each wing extended, 

the vortices were greatly reduced and the T-37 could safely fly five 

kilometers behind the larger aircraft.39 

FRC’s 747 wake vortex studies clearly indicated that use of spoiler’s 

could reduce the severity of wake vortices. After the 747 was reassigned 

to its primary mission-carrying the Space Shuttle orbiter-the vortex 

alleviation studies continued, under the direction of program manager 

Russ Barber. In July 1977, the center began a brief series of tests on a 

Lockheed L- 101 1 TriStar wide-body to determine if the spoiler fix that 

worked so well on the 747 could be applied to other wide-body aircraft as 

well. The test showed that while the spoilers on the TriStar could reduce 

wake vortices, they were not as effective in doing so as the spoilers on the 

747. NASA is continuing wake vortex studies, which can be expected to 

improve the operational safety of future air~raft.~’ 

Two other recent research areas for Dryden have been clear air 

turbulence and pollution of the upper atmosphere. While atmospheric 

pollution is strictly an environmental problem-and a most serious 

one-clear air turbulence can endanger an aircraft by exposing it to 

sudden and extreme gust loadings possibly exceeding its structural 

strength. Private researchers, the FAA, and NASA have always had a 

major interest in turbulence. One of the old NACA’s greatest accomplishments was its work on gust-induced flight loads, work that predated 

World War 11. In the late 1950s and 1960s, NASA flight researchers 

undertook projects on high-altitude clear air turbulence using Lockheed 

U-2 aircraft. As concern about pollution of the upper atmosphere 

became more widespread, NASA sponsored U -2 and Martin WB-57F 

high-altitude sampling flights, as well as the current Dryden Mini-Sniffer 

RPRV program. Gustiness at high altitudes had caused annoying difficulties during some of the Flight Research Center’s work with the XB-70A 

and YF-12 Blackbird. More seriously, clear air turbulence had given 

some commerical aircraft a rough flight, injuring some passengers not 

using their seat belts and occasionally leading to structural failure. 

In response to this interest in atmospheric conditions, Langley and 

Flight Research Center engineers mapped out joint research to provide 

“a limited amount of highly accurate measurements associated with 

mountain waves, jet streams, convective turbulence, and clear air turbulence near thunderstorm^."^^ At the first LaRC-FRC meeting on 3-4 

June 1969, planners agreed to use a NASA-owned Martin B-57B 

226 
A CENTER WITH DIVERSITY 

airplane, a modified medium bomber. In due course it appeared on 

FRC’s flightline. Difficulties with the data-acquisition system delayed the 

planned flights,* but in time the B-57B supported three atmospheric 

science programs: measurement of atmospheric turbulence, sponsored 

by Langley; aerosol-sampling sponsored by the University of Wyoming; 

and detection of clear air turbulence, sponsored by the Department of 

Tran~portation.~~ Combining data from these flights with that from 

many other sources, scientists are developing a better understanding of 

the nature-and fragility-of the upper atmosphere. 

FRC AND THE NEW GENERATIONS OF MILITARY AIRCRAFT 

Because of commitments to the X- 15 and other advanced research 

programs. FRC lacked manpower to participate in new military programs such as the F-4 Phantom! Paul Bikle would have preferred to 

continue the practices of the 1950s, getting involved in as many servieerelated programs as possible. But the easy days of the Cook-Craigie 

procurement plan had long passed, and stronger institutional ties workec‘ 

to prevent close NASA-Air Force cooperation on flight testing of new 

service aircraft. Under new procurement policies, if NASA flew an 

aircraft on loan from the military services, NASA had to pay its operational 

costs. Bikle nevertheless sought cooperation between the military and 

FRC, and because of personal ties dating from his duties as technical director of the AFFTC, he had a great deal of success. Bikle was thwarted 

in his efforts to acquire service aircraft for FRC less by the services than 

by NASA Headquarters, which refused several requests for budgetary 

reasons. 

Aside from research, Bikle needed newer aircraft at the FRC so that 

his pilots could stay current with the latest technology. FRC acquired 

three F- 104N Starfighters, specially ordered from Lockheed in 1963. 

Bikle also got the Northrop two-seat T-38 supersonic trainer. This 

useful and reliable little jet could perform a variety of mission support 

chores, as well as simulating lifting body landing approaches. Bikle’s 

managerial philosophy stressed diversity, which helped save the Flight 

Research Center from the criticisms of those who sought to shut it down 

during the 1960~.~~ 

Following the creation of NASA, FRC was involved in programs with 

various service aircraft: Lockheed F- 104A Starfighter, McDonnell F-4A 

*Meanwhile the B-57B was put to work in proof-of-concept testing of the deceleration 

parachute to be used by the Viking Mars landers. The tests were conducted at the Joint Parachute 

Test Facility at nearby El Centro. For example, see J. M. Groen, Flight Report, Viking Test #7, 28 

April 1972. 

227 
ON THE FRONTIER 

Two of NASA’s special Lockheed F-104N StarjGghters. 

Phantom 11, General Dynamics F- 11 lA, Lockheed T-33 Shooting Star, 

Northrop F-5A Freedom Fighter, Vought F-8C Crusader, Northrop 

YF-17 Cobra, and the McDonnell Douglas F-15A Eagle. NASA had 

other programs that were military related, such as the Blackbirds, 

XB-’70A, and the TACT F- 1 1 1. FRC also acquired airplanes from 

abandoned projects, such as the Northrop A-gA, but did not run 

programs on them. Clearly, then, if FRC’s research using modified 

service aircraft was not as extensive as that of the 1950s, such activity 

remained substantial-certainly as much as the center could support 

during a space-conscious era. 

During the 1960s and 19’70~~ NASA continued to fly the workhorse 

F- 104s as testbeds. Aside from using the Starfighters for X- 15 mission 

support and chase and in support of the lifting body effort, NASA used 

them in a number of short programs such as base drag measurements, 

sonic boom measurements in support of Langley research, and tests of 

“ballute” (balloon-parachute) deceleration devices. In the early 1960s 

FRC flew a brief military-inspired program to determine whether an 

airplane’s sonic boom could be directed; if so, it could possibly be used as 

a weapon of sorts, or at least an annoyance. In December 1965 FRC 

received an ex-Navy McDonnell F-4A Phantom I1 fighter. It flew briefly 

in this project before a wing fuel tank burst, producing a large hole in the 

wing. The pilot landed safely. 

The center received two early General Dynamics F- 11 1A airplanes. 

As a result of a poorly thought-out development specification, both the 

Navy and Air Force had become committed, much against their will, to a 

civilian-inspired “Tactical Fighter Experimental” (TFX) program. This 

called for developing a single aircraft-the F-111-to fulfill a Navy 

fleet-defense interceptor requirement and an Air Force supersonic strike 

aircraft requirement. In retrospect, this was impossible to achieve, 

especially since planners placed priority upon the Air Force requirement, 

and then tried to tailor this heavy landplane to the constraints of 

228 
A CENTER WITH DIVERSITY 

carrier-based naval operations. The naval aircraft, the F- 1 I IB, was 

never placed in production. The Air Force aircraft, which was produced 

in a variety of models, including the F-lIIA, F-IIID, F-IIIE, and 

F-IIIF, as well as an “FB-111A” strategic bomber version, had 

numerous problems, and only the F- 1 1 1 F actually fulfilled the original 

TFX design specification. This was less the fault of General Dynamics 

than of the civilian planners in the Pentagon whose “cost effective” 

inclinations ironically produced the major aeronautical fiasco of the 

1960s-and a costly one at that.* 

The center’s F- 11 1A program was the only program of the 1960s 

that closely followed the earlier pattern of using NACA-NASA flight-test 

specialists to iron out technical problems with a major new weapon 

system. The early F- 1 1 1As had extremely bad engine problems, suffering from compressor surge and stalls. In January 1967 the Air Force sent 

the sixth production F- 11 1A to FRC for testing. The plane did not make 

a favorable impression there. One center pilot stated: 

The early ones were rats. . . . It was like flying in a three-dimensional 

maze. You couldn’t sweep the wings beyond a certain point, you 

couldn’t exceed so much [angle of attack], you couldn’t turn too tight, 

you couldn’t have so much sideslip. . . . It was terrible.44 

NASA pilots and engineers wrung out the airplane in an attempt to solve 

its problems, studying the engine inlet dynamics of the plane to determine the nature of inlet pressure fluctuations that led to compressor 

surge and stall. Eventually, as a result of NASA, Air Force, and General 

Dynamics studies, the engine problems were solved by a major inlet 

redesign. FRG’s work had been crucial to this effort. The center’s second 

F-IIlA, the twelfth built, arrived in April 1969 and was flown in a 

handling-qualities investigation program. Both aircraft were retired 

to the boneyard in 1971. The center’s experience with its later F-11 Is 

(the TACT and IPCS airplanes) was far more pleasant.45 

FRC flew numerous brief programs using service airplanes. A 

Lockheed T-33 Shooting Star jet trainer was flown on a human-factors 

study to evaluate the effects of visibility restrictions upon a pilot’s 

performance during landing; many advanced airplanes would have very 

restricted visibility forward and laterally during landing approach. The 

center undertook a comprehensive study of high-lift flaps as aids to transonic maneuverability with a series of tests on F-104, Northrop F-5A 

*One FRC wag, noted for his pen-and-ink skills, drew a variety of F- 1 1 1 “growth proposals, 

including a cargo C- 11 1, a helicopter H- 1 11, and an X- 11 1 research airplane. His cartoon was 

printed in Avzation Week €3 Space Technology, fortunately without credit. 

229 
d 

ON THE FRONTIER 

In the 1960s, Flight Research Center flew an F-111A prototype in support of the 

seruice-testing of the General Dynamics F-1 1 1 A aircraft. 

Freedom Fighter, and Vought F-8C Crusader aircraft during 1970 and 

1971. Wind tunnel results simply were not reliable for this purpose, and 

the flight-test data would be useful for developing new military aircraft. 

FRC’s work in this area led to the derivation, by the Department of Defense, 

of “agility” criteria for fighter turn rate, buffet, maximum lift, and 

handling qualities. This paid off in the development of a whole new generation of fighter aircraft: the McDonnell Douglas F- 15A Eagle, the 

General Dynamics F- 16A, and the Northrop YF- 17 CobrdF- 18 Hornet. 

The center also used the T-33 for evaluating a self-contained liquidcooled flight garment providing the pilot with heating, cooling, and 

pressure pr~tection.~~ 

DFRC’s most recent exposure to new military aircraft came with the 

McDonnell Douglas F- 15A Eagle and the Northrop YF- 17 and F- 18. 

Involvement with the F- 15 program came out of earlier work with the 

F-15 RPRV model and a desire to have a representative of the latest 

highly maneuverable fighter aircraft. The F- 15 Eagle represented a 

turning point in Air Force doctrine, a return to an airplane designed 

primarily for agility and air-to-air combat-the first since the old F-86 

Sabre. 

The opportunity to work on the Eagle came at a time when some 

engineers and pilots within the agency were grumbling that a return to 

the service-testing policies of the 1950s was long overdue. Dryden 

secured NASA Headquarters approval to request transfer of two aircraft 

from the Air Force’s F-15 Joint Test Force. Its activities were winding 

down-soon some of its aircraft were refurbished and shipped to 

Israel-and two specialized prototypes were available: the second, which 

had been used for propulsion tests, and the eighth, which had been used 

for spin testing. NASA acquired both aircraft on indefinite loan from the 

Air Force. 

230 
A CENTER WITH DIVERSITY 

The center has flown the two aircraft on a variety of research 

missions, two of which have been a major propulsion and performance 

flight test program and research into high angle-of-attack stall-spin 

phenomena. At the request of the Air Force, the Dryden F- 15 test team 

also investigated discrepancies between predicted and measured drag 

values. In flight, the F- 15 had greater base drag-drag around the aft 

end of the plane-than tunnel tests had predicted. This problem has 

afflicted a range of aircraft-one notable example being the X- 15-and 

remains an area of concern to aerodynamicists. Data from the F-15 

full-scale flight tests were also used to validate data taken during testing 

of the 3/8-scale F- 15 RPRV drop model. In another effort to improve 

wind-tunnel prediction techniques, a small 10” cone was installed on the 

nose boom of one of F-15s. The shape has been tested in 23 wind 

tunnels, and the data taken in flight up to mach 2 speeds were compared 

with wind tunnel data, furnishing an assessment of the airflow quality 

and turbulence levels generated in the tunnel^.^' 

In the early 1970s the Air Force pressed for development of a new 

generation of lighweight fighters-single-seat jet aircraft “optimized” for 

agility and air combat maneuvering, with high thrust-to-weight ratios 

(above 1 to l), and good acceleration. Out of this interest came the 

so-called “Lightweight Fighter” program, which involved construction of 

two technology demonstrators, the single-engine General Dynamics 

YF- 16 and the twin-engine Northrop YF- 17 Cobra. Midway down the 

development path the stakes changed; what had been a technology 

demonstration became a Department of Defense competition for a new 

fighter for both the Air Force and Navy, and for allied nations as well. 

Eventually the YF-16 was ajudged superior; the Air Force adopted a 

derivative of it, the production F-16A. The Navy, unhappy with the 

outcome, proceeded independently with a derivative of the YF- 17 

One Of Dvden Flight Research CenterS two F-15A Eagles on an early test flight. 

23 1 
ON THE FRONTIER 

Cobra, this evolving into the Navy’s Northrop F-18 Hornet fighter 

program. After sitting briefly in storage, the two YF- 17 prototypes flew 

again, this time as development aircraft for the proposed F-18. At the 

request of the Navy, Dryden flew the first YF- 17 for base drag studies 

and to evaluate the maneuvering capability and limitations of the aircraft. 

NASA pilots-all of whom got at least one flight in the plane-and 

engineers examined the YF- 17’s buffet, stability and control, handling 

qualities, and acceleration characteristics. 

The YF- 17 shocked many of the center’s pilots, trained on earlier 

combat aircraft. “I was astounded,” one center pilot recalled. “That 

airplane really is a generation ahead of anything else. It’s got twice the 

performance of current-day airplanes like the F-4, and some of the 

others. It’ll climb twice as fast, and it’ll burn half the fuel-just 

phen~menal.”~~ Wistfully, the center’s personnel saw the shapely little 

YF-17 depart, on its way to help out Northrop and the Navy on the 

F- 18. The greatest shock came when many within NASA realized that 

the YF- 17 typified industry’s growing tendency to develop aircraft 

independent of NASA research. “Now the tail’s wagging the dog,” one 

engineer stated. “Industry goes out and builds an airplane like the F- 16 

and the F-17. . . . NASA says, ‘let’s take a look at it, let’s assess the 

thing.’ ”49 

This problem was succinctly summarized in a memo from a senior 

engineering administrator to Dryden Director David Scott in January 

1976, before the YF- 17 arrived. The administrator argued for NASA to 

acquire an F- 16, citing the record of the NACA in the 1950s. “We must, 

however, recognize the fact that we may not have as much to contribute 

Dryden Flight Research Center continues to study advanced military aircraft. This is one of 

the two Northrop YF- 1 7 Lightweight Fighter (L WF) prototypes that center pilots evaluated in 1976. 

232 
A CENTER WITH DIVERSITY 

these days as we had in the past.” After discussing the center’s work on 

the Century series in the 1950s, he went on: 

NACA was in that time period an acknowledged leader in the fields of 

aerodynamics, stability and control, aerodynamic loads, buffet, flutter, 

propulsion performance, and possibly others. NASA no longer enjoys that 

esteemed position in the aeronautics world, largely due to default. NASA was 

actually unable to provide any substantial guidance or assistance to the designer of the YF-12 and SR-71. Thus, NASA is now in an extremely weak 

position to bargain for participation in any new aircraft program [however] 

NASA should be flight testing new aircraft if for no other reason than to keep 

abreast of te~hnology.~” 

Certainly NASA occasionally appears to be playing catch-up to the 

American aircraft industry. But in many fields-such as transonic and 

supersonic aerodynamics, supercritical wing technology, control system 

technology, and aero-thermal loads-NASA is well ahead. Those areas 

where NASA seems weakest relate to the early design of new military 

aircraft. At worst it is a problem that can be solved by encouraging basic 

research and involving the centers in new aircraft development programs 

at an earlier date-i.e., before the first flight of an airplane or, better yet, 

before the design is “fixed” on the drawing board. At best (and this is a 

view held by many), the problem is fading rapidly now that the space 

program makes fewer demands on the time and efforts of the old 

aeronautics centers, Langley, Ames, Lewis, and Dryden. NASA will 

continue to have much to offer other government agencies and industry.. 

One positive step, coming on the heels of Apollo, was the creation of a 

Military Aircraft Programs Office within OART in September 197 1 , charged with overseeing the agency’s support of Air Force and Navy 

aircraft project^.^' 

Dryden’s flight testing of service aircraft is certain to continue. The 

center is currently involved in a major Navy-sponsored study of the 

lateral (roll) stability and control characteristics of the Grumman F- 14A 

Tomcat fighter in low speed at high angles of attack, in an attempt to 

develop a better understanding of the spin departure characteristics of 

the aircraft. This is a typical 1950s NACA-type problem-solving “helping 

hand” study aimed at alleviating problems that have cost the Navy some 

airplanes and flight crews. Center pilots have also flown such experimental military aircraft as the YC- 14 and YC- 15 advanced STOL transports, 

and even the Rockwell B-1 strategic bomber. It is to the credit of the 

staff at Dryden that they have sought participation in demanding 

projects and programs. That spirit, so typical of Hugh Dryden himself and 

so much a part of the Dryden facility’s tradition, must be cherished in the 

years to come. 

233 

e * 

11 

A Center at the Crossroads: 19’76- 1981 

On 26 March 19’76 the Flight Research Center opened its doors to 

hundreds of guests for the dedication of the center in honor of Hugh 

Latimer Dryden. The evening before, an Air Force Douglas C-9 

executive transport had flown into Palmdale with a group of official 

visitors, including Dryden’s widow and other relatives and prominent 

NASA officials. 

It was a beautiful day, clear and sunny, typical of the Antelope 

Valley. The dedication was very much a local event; following Center 

Director David Scott’s opening remarks, the Antelope Valley High School’s 

symphonic band played the national anthem. Then came the invocation, 

followed by recognition of the invited guests. Dryden, a man of total 

humility, received praise from all quarters. NASA Administrator James 

C. Fletcher, Senator Frank Moss, and former NASA Administrator T. 

Keith Glennan all spoke of his foresight and resourcefulness. Mrs. 

Dryden unveiled the memorial bust, and with her remarks and those of 

Scott, the formal ceremonies came to an end. After a buffet lunch, 

visitors flocked around the center’s research aircraft and the official 

guests returned to Washington. 

That night, the center’s staff held a more informal celebration in the 

Longhorn, the ever popular gathering spot on the outskirts of Lancaster. 

In contrast to the placid tributes of noon, the conversations in the 

Longhorn were more questioning. The lifting body program had ended. 

The National Hypersonic Flight Research Facility aircraft faced an 

uncertain future.* The Blackbirds were the only project that seemed to be 

continuing Dryden’s tradition of frontier-probing research. On the 

horizon loomed the Space Shuttle-but it was less a Dryden project than 

one for the NASA space centers, notably Johnson. As earlier in the 

center’s history, doubts were expressed about its future. Could Dryden 

continue as an independent center in the budget-conscious post-Apollo 

*It would be canceled 18 months later (chap. 8). 

235 
a 

ON THE FRONTIER 

As Center Director David Scott IL 

on, Mrs. Hugh L. Dryden unv 

the memorial to her husband at 

dedication of the NASA Hugh 

Dryden Flight Research Center, 

March 1976. 

,Ok 

leils 

the 

L. 

26 

period? Did Headquarters fully appreciate the unique flight-research 

capabilities of the center? Were non-flight-test-oriented administrators 

going to homogenize it-turn it into a copy of the other research centers? 

Many seemed to be celebrating the dedication as an end to what had 

been, rather than as a promise of what might be.’ 

WHITHER DRYDEN? 

Dryden’s recent administrative history had certainly been unsettled. 

On 31 May 19’71 Paul Bikle had retired from NASA. Bikle had made a 

major imprint on the center, and everyone there was aware and appreciative of his role, especially in actively seeking a broad research base. Bikle’s 

236 
AT THE CROSSROADS 

deputy director, De E. Beeler, had taken over until October, when Lee 

R. Scherer became director. His arrival marked a major change in leadership style. Williams and Bikle had been closely attuned to flight testing 

and flight research; they were strong managers with a bias toward aeronautics; they were individualists who favored a great deal of personal 

and center autonomy. Their immediate successors were more closely in 

tune with a NASA Headquarters management philosophy emphasizing 

close consultation, coordination, and dependency upon Washington for 

decisionmaking. Bikle’s successors functioned more as agents of Headquarters in the same sense that project engineers acted at the bidding of a 

program manager.2 

Lee R. Scherer, the center’s third director, was a graduate of the U.S. 

Naval Academy with advanced degrees from the Naval Postgraduate 

School and the California Institute of Technology. A naval aviator, he 

had served in the 1950s as a special assistant to the assistant secretary of 

the Navy for research and development, had helped create an antisubmarine warfare center for NATO, and in 1962 had joined NASA on 

!ntc *r Director Lee R. Scherer. 

237 
ON THE FRONTIER 

temporary assignment as manager of the Lunar Orbiter project. After 

retiring from the Navy in 1964 with the rank of captain, he had risen 

within NASA to direct Project Apollo’s Lunar Exploration Office, where 

he was responsible for lunar science. A gregarious, athletic individual, 

Scherer brought to the center a keen awareness of current space and 

management interests at Headquarters. During his tenure, the Flight 

Research Center largely continued to run the programs established 

during the Bikle era. Appointed director of the Kennedy Space Center in 

1975 Scherer was replaced at FRC by his deputy, David R. S~ott.~ 

The fourth center director, Scott had joined FRC in August 

1973 as deputy director, following the retirement of De Beeler, one of 

the last of the NACA old timers. Scott, a West Point graduate and career 

officer, came to the center as an Air Force colonel-he retired in March 

19’75. An astronaut of note, Scott had made three flights in Gemini and 

Apollo. Though a test pilot by training, Scott brought to the center the 

same orientation and interests as his predecessor Scherer, for whom Scott 

had worked for nearly two years. Both sought to bring Dryden more in 

line with a standard relationship with the other centers and Headquarters; 

gone was the sometimes paternalistic padrone-Williams or Bikle; in his 

place was a more tightly structured bureaucracy. This rankled many 

veterans who were used to a free-wheeling style. Some doubted the 

devotion of the new leaders to atmospheric flight-testing; cancellation of 

NHFRF, thwarting of the mini-Shuttle research aircraft, termination of 

the Blackbird effort were all seen as symptomatic of this supposed 

non-aeronautics ~rientation.~ 

Scott retired in 1977. His deputy Isaac “Ike” Gillam had run the 

approach and landing tests of the Shuttle at Dryden (p. 239). With 

background in Air Force flight assignments and management of launch 

vehicles for NASA, a friendly disposition and obvious ability, Gillam had 

the support of many on the staff who hoped he would become the new 

director. Until he was so appointed in June 19’78, Gillam was not inclined 

to be a mere g are taker.^ As acting director and then permanent director, 

his was to be a challenging assignment. With a new administration in 

Washington pledged to economy, NASA and other agencies would be in 

a budget squeeze. Dryden would be buffeted by internal wars of 

institutional assessment, which would determine where NASA’s smaller 

budget would go. At the same time, the Shuttle test flights would bring 

Dryden massive, unaccustomed publicity. 

SHUTTLE CONES TO DRYDEN 

NASA’s thinking on reusable lifting-reentry spacecraft reached 

fruition in development of the Space Shuttle. After studying various 

proposals, NASA awarded study contracts to North American- Rockwell 

238 
Center Director Isaac ‘7 ‘ke” ‘G illa .m. 

(now Rockwell International) and McDonnell Douglas in July 1970. The 

design characteristics selected for the craft included a delta wing and a 

2000-kilometer “cross-range” during reentry. Various designs were 

submitted, including vehicles launched from the backs of other winged 

reentry vehicles, vehicles launched on top of boosters, and vehicles 

attached to large fuel tanks and solid-fuel boosters-the “parallel burn” 

configuration, in which both liquid-fuel engine and solid-fuel booster 

would burn during ascent. In March 1972 NASA selected the parallelburn approach and on 16 July selected Rockwell’s proposal for development. 

Construction of the first Space Shuttle orbiter, vehicle OV- 101, 

started at Rockwell’s Downey, California, plant on 4 June 1974. Components were delivered to Rockwell’s Palmdale plant near Edwards, where 

final assembly began in August 1975. The OV-101 was rolled out 17 

September 1976. The hefty craft, the size of a Douglas DC-9 jet 

transport, was christened Enterprise, a name fraught with historic 

significance-and also tinged with the banalities of television science 

fiction. In January, in a scene reminiscent of building the Pyramids, the 

Shuttle was trucked overland from Palmdale to Dryden. Meanwhile, 

NASA had bought a Boeing 747 and returned it to the manufacturer for 

modification, so that the Shuttle could be mounted on the back of the 

239 
c 

ON THE FRONTIER 

747. So connected, the Shuttle would be carried aloft for its first flight 

tests. Later it would be ferried from one site to another the same. way.6 

The Space Shuttle was an ambitious design. It had a body length of 

over 37 meters, a height of over 17 meters, and a wingspread in excess of 

24 meters. It combined reaction controls for spaceflight and aerodynamic controls for glide to earth. The reaction controls would not be 

installed for the approach and landing tests. If the craft went out of 

control or collided with the 747 after launch, the crew of two would 

eject. Planning for the approach and landing tests was as complex as for 

any other research airplane. And there was the added factor of 

publicity; everything that happened at Dryden would be headline news. 

In the fall of 1974, the Air Force and NASA executed a joint 

agreement to establish Space Shuttle facilities at Edwards. Edwards was 

already designated as the test site for the Shuttle’s approach and landing 

tests and as the prime landing site for the first orbital flights. Within 

NASA, the Shuttle would be under the overall control of Johnson, with 

FRC in a supporting role.’ 

By the time of the Dryden dedication, Shuttle test plans were 

nearing completion. The Shuttle road was almost ready. In January 

1977, Enterprise was moved to Dryden. Immediately the center, which 

had done its most spectacular work under conditions of almost total 

privacy, was the focal spot of national attention. Ralph Jackson, Dryden’s 

ebullient director of public affairs, had his hands full. Inside the 

headquarters building, Johnson engineers and technicians roamed the 

halls. Outside, Johnson astronauts and pilots zipped around in T-38s 

and a NASA Grumman Gulfstream I1 Shuttle trainer simulated Shuttle 

approaches and landings. The Boeing 747 crews readied themselves for 

the first flights. Press and television commentators wandered about, 

interviewing and photographing anything that moved. It was the Cape 

come to the Mojave, a scene more familiar to Cocoa Beach or Houston; 

indeed, the reporters who covered the Shuttle were mostly veterans of 

Mercury, Gemini, Apollo, Skylab, and Apollo-Soyuz. 

The flight test program had three phases: captive, captive-active, 

and free flights. The unmanned captive flights would simply demonstrate whether the combination-which wags dubbed the worlds largest 

biplane-could fly together safely. In the captive-active trials, an astronaut 

crew would ride in the Shuttle. Finally it would be launched from the back 

of the 747 and flown down to a landing. During the captive flights and the 

first of the free flights, the Shuttle’s blunt base would be faired over with 

a tailcone to reduce buffeting on the 747’s vertical fin; as another 

precaution, Boeing had added two more vertical fins to the 747’s 

horizontal stabilizer. Toward the end of the flight trials, NASA hoped to 

launch the Shuttle without the tailcone, which would reduce the Shuttle’s 

lift-to-drag ratio, resulting in a descent path similar to what it would have 

240 

I 
AT THE CROSSROADS 

upon returning from orbit. A series of high-speed taxi tests by the mated 

747 and Enterp-zse in mid-February 1977 went without a hitch.* 

On the 15th the first Shuttle flight proved to be a media event 

unparalleled in the brief history of Dryden. For the previous week, 

Johnson and Dryden public affairs officials had been on hand to meet the 

demands of the hundreds of media representatives who left plusher 

locales for the sunny but blustery desert. Those who spent the night in 

Lancaster and Palmdale had to get an early start. At 5 a.m., the sky was still 

black and clear, the stars as brilliant as always, the temperature in the low 

20s. Autos moved along the Sierra Highway, down Avenue E, then north 

on 120th Street East. Despite the urban-sounding names, the surrounding country was bare, scrub desert broken only by an occasional homestead. 

As the sky began to lighten, Joshua trees and the low hills near Hi Vista 

were outlined. The revolving beacon at Edwards pulsed brightly on the 

northern horizon, and the 6 a.m. news on KNX reported that the Shuttle 

would fly today. Dryden itself was controlled pandemonium, the public 

affairs trailer a madhouse. By 6:45 the sun was spreading a warm glow 

through the thin fog covering the lakebed. Those present prepared to 

convoy out to the runway; meantime they drank coffee and watched the 

TV monitors in the public affairs trailer.8 

By 7 a.m., the Shuttle launch crew, Fitz Fulton, Tom McMurtry, Vic 

Horton, and Skip Guidry, were in the 747, the inert Shuttle riding on 

top. No sooner had the reporters journeyed from Dryden to the press 

site along runway 04-22 than the Air Force staged an impromptu 

airshow: the YC-14 took off, followed by the B-1, some T-38s, an 

F-4, and the F-16. Finally those at the site watched the 747-Enterprise 

combination taxi slowly past the Air Force’s two large hangars, down to 

the west end of 04-22. There it held while the test crew completed final 

checks. Aloft, two NASA T-38s flew over, as if impatient to get on with 

the flight. Camera crews set up their tripods, shivering in the brisk desert 

morning. It was a beautiful day. Right down the center of 04-22 flew a 

gaggle of geese-a large V honking along, heading east, unperturbed by 

the consternation they were causing. Geese and jet engines do not mix, so 

NASA delayed the departure of the 747 a little longer. Finally, the 747 

started to roll down the runway with that peculiar whine so typical of 

large fan-jet airplanes. 

The world’s most improbable aerial combination, after a run of 1800 

meters, became airborne, climbing ponderously toward the east, above 

the lake. For 125 minutes, this strange hybrid flew along, anxiously 

attended by T- 38 chase planes, before Fulton and McMurtry returned it 

gently to earth. First flights are always cautious, and on this one, the test 

crew held the combination to a maximum altitude of 4900 meters and a 

maximum speed of 463 kilometers per hour. Everything went well; the 

747-Enter@e flew closer in performance to a standard 747 than simulations 

24 1 
ON THE FRONTIER 

had predicted. Nothing serious had happened, a tribute to the test 

planning. That afternoon and evening, the dark interior of the Longhorn echoed to the jubilation of Dryden, Rockwell, and Boeing personnel. 

The Shuttle had taken to the air. 

Back at Dryden, over the weekend engineers worked up the data 

from the flight. At a technical and crew briefing on Monday, the word went 

foGh: “Testing can go on to expand the envelope as planned.” The 

critical concerns of buffeting, flutter, and tail loads proved to be no 

problems. After five complete successes, NASA abandoned a planned 

sixth flight, deeming it unnecessary. While the next series of tests was 

being prepared, the 747 flight crews temporarily returned to more 

prosaic duties such as flying the YF-12 Blackbird on its coldwall tests 

(p. 195).’ 

SHUTTLE SUMMER 

NASA had already selected four astronauts for the Shuttle 

landing tests, placing Fred W. Haise and Charles G. Fullerton on one 

crew and Joe H. Engle (the former X- 15 pilot) and Richard H. Truly on 

the other. Haise, a former center pilot, had flown on the ill-fated ApoZZo 

I3 mission. They prepared for the Shuttle program by practicing in a 

ground simulator and flying a much-modified Grumman Gulfstream 11. 

Other pilots flew the center’s Jetstar to test the Shuttle’s microwave 

scanning-beam landing system. In addition, Dryden managers worked 

closely with their Johnson counterparts to prepare for a most important 

part of the Shuttle test program: arranging for the Houston center to 

control the mission while it was in progress at the desert. Dryden had 

controlled the captive inert flights, but Mission Control Center at 

The Space Shuttle Orbiter Enterprise cruises atop its Boeing 747 launch aircraft during 

the Space Shuttle approach and landing tests, 1977. 

242 
b 4 1 B! D 

AT THE CROSSROADS 

Johnson would have primary responsibility for running subsequent 

missions, starting when the 747 and Enterprise backed away from the 

Shuttle mate-demate facility and began taxiing to the runway. By 

mid-June all was ready, and the Shuttle flight test program moved into its 

next phase. lo 

On 18 June 1977, the 747 and Enterprise combo went aloft on the 

first “captive active” test. Inside the Shuttle, Fred Haise and Gordon 

Fullerton had a magnificent view; not being able to see any portion of the 

carrier aircraft added to the illusion that they were alone in the sky. The 

flight lasted nearly an hour and all objectives were achieved. The test 

data indicated that the Space Shuttle was buffet- and flutter-free up to 

the maximum speed attained on the flight, over 320 kilometers per hour. 

The next captive-active mission, flown by Engle and Truly on 28 June, 

involved high-speed flutter tests up to 500 kilometers per hour. It too was 

successful. NASA concluded that the four flights originally scheduled for 

the captive-active phase could be safely cut to three. On 26 July Haise and 

Fullerton completed the last of the captive-active flights. During this last 

mission, 747 pilots Fitz Fulton and Tom McMurtry flew a launch 

separation profile, pushing the 747 over into a shallow dive at 8500 

meters and lowering the 747’s landing gear to simulate the free-flight 

launch conditions. During approach of the 747-Enterprise combination to 

landing, Haise and Fullerton lowered the Shuttle’s landing gear to check 

its operation. It went smoothly. 

Indeed, the captive-active phase of the Shuttle testing had gone 

pleasingly well. Some equipment problems had been experienced; auxiliary power units leaked or overheated, computers were “voted” off-line 

by other computers, and sometimes a computer tried to take the square 

root of a negative number. These were small concerns that could be 

remedied by minor fixes or software changes. The important fact was 

that the Shuttle and the 747 were a safe flying combination. Now NASA 

could move to the next phase of the approach and landing tests: the 

actual free-flight testing of the Enterprise. The flock of news personnel, 

who had left the desert in droves after the first captive flights, now 

swarmed back. 

During the week of 8 August, project officials concluded a two-day 

Shuttle readiness review and a mission readiness review; all conditions 

were “go.” Most visible-and audible-of the preparations were the Shuttle 

simulation flights that Fred Haise and Gordon Fullerton made in the 

Gulfstream I1 training aircraft; for the few days prior to the flight, the 

center echoed to the occasional rumble of the Gulfstream and its T-38 

chase planes climbing out over the lake following another approach to 

landing, or the center’s Jetstar checking the microwave landing system. 

The flight plan called for the 747-Enterprise to take off at 8 a.m., 

from runway 22 and climb to the west. The two mated craft would enter a 

243 
c e 

ON THE FRONTIER 

The Dryden Flight Research Center's Lockheed Jetstar, which has been used for a variety of 

general-purpose airborne simulation studies, general-aviation research, and support of the 

Space Shuttle approach and landing tests. 

racetrack pattern, flying south toward Los Angeles, turning north over 

the mountains, and coming up the east side of Rogers Dry Lake. The 

craft would nose into a shallow dive from an altitude of over 8500 meters. 

At 7300 meters and an airspeed of approximately 515 kilometers per 

hour, Fred Hake in the Shuttle would press a square white button on the 

Shuttle's instrument panel, triggering explosive bolts that would separate 

the Enterprise from the 747. If all went well, Fulton would roll the 747 into 

a descending left turn, and Haise would pitch up the 75-ton Enterprise to 

the right. At 6200 meters Hake would initiate a practice landing flare 

to evaluate the handling qualities of the Enterprise. Then, sinking like a 

rock, the astronaut crew would begin a gradual 180" turn to position the 

Enterprise for a 320-kilometer-per-hour touchdown on lakebed runway 

17, which, at over 11 kilometers, was the longest of the Rogers runways. 

The flight attracted massive public attention. Over 1000 reporters 

flocked to Dryden, many from abroad. Parking had to be prepared for 

the public viewing sites west of Dryden, and the VIP and press sites along 

runway 04-22 and the west shore of the lakebed, parallel to runway 17. 

Motels as far away as eastern Los Angeles were booked solid. A wide 

range of aviation personalities, including NASA Administrator Robert 

Frosch and such pioneers as Jimmy Doolittle, were present. 

As with most test flights, the preparations took days of hard work at 

all levels. The event came alive in the early morning of 12 August. At 3 

a.m., the first reporters left Lancaster and Palmdale for the lakebed. 

Once again, the night was perfectly clear; after driving up 120th Street 

through the base gate, the cars made their way to the FAA radar facility 

by Hospital Road on old South Base, turned right, and drove through an 

Air Police checkpoint. Those with authorizations continued on toward 

244 
AT THE CROSSROADS 

the runway site or the lake. The lake was better, at least for those with a 

handle on the past and an awareness of the present. Eerily quiet and still, 

the lake seemed unconnected with civilization. Further away could be 

seen the night lights of the mines at Boron and the bustle of activity at 

Dryden. The Air Force side of the field was still and dark, except for 

watchlights and the tower and runway lights. 

For those interested in omens, the Shuttle’s day began with a meteor 

shower. Looking up toward the Milky Way, clearly visible as a faint 

patchy white in the crisp desert sky, observers saw a rain of fire, with 

meteors coming down by the minute. There were fireballs breaking apart 

in greenish-white trails, streaks of russet, streaks of yellow. Then came 

the desert dawn, the familiar yellow glow lighting up the eastern sky, 

shining through high clouds, and bathing the rocky outcroppings of 

Leuhman Ridge in orange, and finally reaching down to illuminate the 

broad baked expanse of Rogers. The lights on buildings dimmed, and 

soon an Air Force helicopter clattered noisily over the lakebed, joined by 

another from Dryden. Far from the lake, between 60 000 and 70 000 

visitors streamed along the Sierra Highway and Rosamond Boulevard into Edwards; at one point, the trafficjam stretched 16 kilometers. 

As journalists whiled away the time setting up equipment and sipping 

coffee from a Rockwell courtesy van, the technicians, engineers, and 

flight crews at Dryden readied themselves for the flight. 

Finally all was ready, and the 747-Enterprise backed out of the 

mate-demate gantry at Dryden, ran up its engines, and began the long 

taxi. The Air Force Huey still clattered above. The first of the T-38 

chase planes whistled aloft. The 747-Shuttle reached the east end of 

runway 22, turned, and held for the last checks. At 8 a.m., right on 

schedule, Fulton called up full power; the combination, with surprisingly 

little noise, began to roll and nosed aloft, followed by two T-38s. The 

aircraft climbed into the prescribed racetrack pattern, joined by the other 

three chase T-38s. On the ground, the reporters waited for the big 

moment. 

The air launch had been scheduled for 8:45. In fact, higher-thannormal temperatures at altitude caused the climb to take longer than 

planned. The 74’7-Shuttle moved majestically around the racetrack, 

plainly visible most of the time from the lakebed. The low sun obscured 

the view of its approach to launch, but video coverage from one of the 

T-38s outfitted with a portable camera was stunning. The formation 

continued over Saddleback Butte to the Edwards bombing range. Roughly 

48 minutes into the flight, the 747-Shuttle was due east of Rogers lake, at 

an altitude of 8654 meters. Fitz Fulton nosed into a shallow dive. Fred 

Hake radioed Fulton, “The Enterprise is set; thanks for the lift.” Then he 

punched the separation button. Seven explosive bolts detonated and the 

Shuttle was flying on its own at 7346 meters. The 747 pitched down 

245 
L 

ON THE FRONTIER 

slightly and rolled into a diving left turn, and Haise briefly pitched up to 

the right. He initiated a practice landing flare at about 460 kilometers per 

hour and made moderate lateral control inputs to evaluate the Shuttle’s 

response. The big delta handled well. Because of the Shuttle’s low 

lift-to-drag ratio, it would remain aloft only for about five minutes. Later, 

after removing the drag-reducing tailcone, the Shuttle would sink to 

earth in about two minutes, a descent rate similar to the X- 15’s. 

On the ground, the separation had been seen by some with binoculars and sun shields. Soon, it became visible to all. The 747 flew alone, 

trailed by a single T-38, while to the northeast a white speck could be 

seen growing in size at what seemed a remarkable rate, attended by four 

T- 38s. The cameramen started clicking furiously, and exclamations 

sounded on all sides. The Shuttle descended over Leuhman Ridge, 

passed across Highway 58 at Boron, turned west toward Peerless Valley, 

swung around over North Edwards, and lined up on runway 17. 

Houston’s Mission Control radioed Haise that the Enterprise had a lower 

lift-to-drag ratio than predicted by tunnel tests. In fact, however, the 

ratio was just as predicted; Houston had miscalculated. The error caused 

Haise to fly the final approach at a higher speed, conserving energy to 

prolong the glide. As a result, the Shuttle was “high and hot” on its final 

approach. Realizing that the Enterprise would land long, Haise deployed 

the craft’s speed brakes from 30 up to 50 percent. At 275 meters altitude, 

Haise began the landing flare. As the Enterprise leveled out, he deployed 

the landing gear. The Shuttle landed long by about 900 meters at 340 

kilometers per hour, nearly 5% minutes after launch. The Shuttle coasted 

The Rockwell Space Shuttle Orbiter Enterprise glides to a landing after itsfirst freeflight 

during approach and landing tests at Dryden Flight Research Center, 1977. 

246 
b Q 

AT THE CROSSROADS 

for over 3 kilometers before stopping on the south lakebed; as it slowed, 

its T-38 chase planes streaked by. Soon the 747 and its lone chase 

plane swept majestically over the landing site. The first Shuttle free 

flight had been a success. Now all that was left for most at the lake was the 

long trip around the base to Dryden, a quick lunch, and the afternoon 

press briefing. For the engineers, however, the task of data reduction had 

just begun. l2 

After the press conference, many called it a day and went to one of 

the many parties being hosted by mission personnel in and around 

Lancaster. Most wound up at the main blow-out, held at Lancaster’s Delta 

Lady saloon. Others settled for the more tranquil but no less joyous 

environment of the Desert Inn or Mr. B’s Twin Lakes Inn outside 

Palmdale. Shuttle obviously flew well-better than the Gulfstream simulator. 

The major remaining question was how the Shuttle would behave 

without its tailcone. This actually involved two considerations. One was 

whether the buffet from disturbed air caused by removal of the cone 

would cause structural problems for the 747’s vertical fin during the 

climb. The other was whether the Shuttle’s low lift-to-drag ratio-made 

even lower by removal of the tailcone-would present serious piloting 

problems. After all, the descent rate of the craft would just about double, 

reducing flight time from over five to just over two minutes. Pending a 

decision to fly “tailcone off,” Shuttle testing continued with the Enterprise’s 

blunt end still sporting the pointed tailcone. 

Rain on the lakebed and other delays deferred the next free flight to 

13 September, when former X-15 pilot Joe Engle and copilot Dick 

Truly dropped down to the lake, all the while taking data on the craft’s 

longitudinal, lateral, and directional response and lift-to-drag and flutter 

characteristics during approach and landing. Nothing unusual aloft had 

occurred, but on the ground a power surge at Dryden had briefly caused 

a loss of all radar data. Fortunately, after a few minutes everything had 

come back on line and the flight had continued. Ten days later, Fred 

Hake and Gordon Fullerton completed the third Shuttle free flight, and 

events progressed so smoothly that NASA determined to commence 

tailcone-off testing with the very next flight. l3 

At first, NASA and Rockwell had thought that a series of captive 

flights with the Shuttle minus its tailcone might be necessary to evaluate 

whether the buffeting loads on the 747’s vertical fin were acceptable. 

Mission planners soon realized that there was little point in such flights. 

The 747 could take off with the Shuttle; if the buffeting seemed excessive, 

the craft could simply abort the mission and land on the lakebed. In 

preparation for the flight, Rockwell and NASA technicians removed the 

tailcone from the Enterprise and replaced it with a configuration identical 

to what the Shuttle would have during reentry from space, including the 

three main Shuttle engine nozzles and the much smaller nozzles of the 

247 
r 

ON THE FRONTIER 

orbital maneuvering subsystem. By this time, the massive press attention that had focused on the earlier Shuttle flights had abated and 

day-to-day activities at Dryden were more tranquil. 

Mission planners decided that, during the takeoff roll and liftoff, Fitz 

Fulton would report any severe buffeting in the cabin. Bill Andrews 

would monitor the loads on the 747’s tail, and if he deemed them 

excessive, he would call “data abort,” terminating the flight. If the 747 

was still on the runway, this meant chopping power and stopping. If just 

airborne, the 747 could land straight ahead on the lakebed. If airborne, 

Fulton and Tom McMurtry would gingerly return the craft to Edwards. 

The actual flight on 12 October 1977 came off without difficulty. 

Again there was the early morning procession to the south lakebed and 

the long wait until takeoff, while some Air Force Phantoms shot landing 

approaches. When the 747-Shuttle rolled down the runway this time, 

observers watched for any indication of an abort. Then it was airborne 

and climbing out to the east, with no visible problems. At Dryden and 

Johnson, engineers checked monitors. The tail loads were within acceptable boundaries. After about 40 minutes, the 747-Enterprise became 

visible to the north, approaching the drop. Cameramen peered through 

telephoto lenses to catch the moment of separation. Fulton pushed into a 

shallow dive at 7680 meters above the desert. Thirty-eight seconds later, 

Joe Engle triggered the explosive bolts. The separation occurred over 

Peerless Valley; Enterprise nosed down sharply, descending over North 

Edwards on final approach to runway 17. It quickly became apparent 

that Enterprise would land right in the aiming area. The steep diving 

The Enterprise on itsJirst tailcone-ofiflight, 12 October 1977. 

248 
* e Y ?i rr d 

AT THE CROSSROADS 

descent, with the Shuttle plunging to earth followed by its T-38 chase, 

brought exclamations of surprise even from those who had witnessed the 

earlier tailcone-on flights. Removing the tailcone certainly made a 

difference. In what seemed an incredibly brief time, Engle had pulled 

out of the dive into the landing flare and deployed the gear. There was 

no excess energy to worry about this time, and Enterprise plunked down, 

streamin a roostertail of playa dust, 2 minutes and 34 seconds after 

launch .3 

During the very brief flight the Shuttle had flown well, confirming 

earlier predictions and simulations. It was, in effect, simply a big X- 15. 

The next question was whether the Shuttle could be landed with 

confidence on a confined runway. It was a critical issue since NASA 

planned landing the Shuttle on 4600-meter runways at Vandenberg and 

Kennedy. For the next tailcone-off flight, NASA planned to land the 

Enterprise on the 4600-meter runway at Edwards. So far, aside from the 

high and hot first landing, the Shuttle had had little difficulty in landing 

at a chosen spot on the lakebed runways, even with the tailcone off. 

Encouraged, NASA scheduled the fifth Shuttle free flight for 26 0ct0ber.l~ 

In that flight Enterpme encountered control problems just at touchdown. 

The Shuttle had been launched at an altitude of 5800 meters over the 

desert for a straight-in approach. Mission commander Fred Hake flew a 

536-kilometer-per-hour approach profile down to the flare maneuver; 

the Enterprise lost speed very slowly-much slower than the Shuttle’s 

Gulfstream I1 simulator. Passing across the runway threshold, the 

Enterprise was about 40 kilometers per hour faster than planned. Haise 

used the split-rudder speed brake to slow the craft and nosed down to 

force it onto the runway at the planned impact point. Instead, the 

Enterprise entered a left roll, which Haise corrected, touched down on its 

main landing gear, and bounced back into the air. Hake had brought on 

a “PIO’: pilot-induced oscillation. Copilot Gordon Fullerton told Haise 

to relax his grip on the controls, and the Enterprise damped out its rolling 

motions. It touched down again, bounced more shallowly, then touched 

down for the final time before coasting to a stop. The flight had an 

important VIP observer: Charles, the Prince of Wales. Prince Charles, a 

Royal Air Force pilot, was in the United States as part of a goodwill tour. 

While in Houston, he had “flown” the Shuttle simulator with Haise and 

Fullerton. Interestingly enough, during one “touchdown” the craft had 

bounced and Prince Charles had encountered the same sort of lateral 

PI0 during the ensuing skip. The rugged arrival prompted NASA 

briefly to reconsider adding an additional tailcone-off flight, but mission 

planners decided that it was unnecessary. The astronauts themselves had 

no reservations about the Shuttle’s ability to land on concrete runways at 

Kennedy and Vandenberg, and their feelings did much to influence the 

decision not to add an extra flight. Dryden did undertake a landing study 

8 

249 
ON THE FRONTIER 

of the Shuttle the better to understand its low-speed handling and 

control characteristics. With their usual penchant for thoroughness, 

center personnel wanted no unresolved questions or doubts when the 

Shuttle whistled in to land from a mach 25 reentry sometime in 1981.16 

The fifth Shuttle free flight concluded Enterprise’s flight testing. 

Dryden now prepared for the task of ferrying the Enterprise aboard the 

747 to NASA’s Marshall Space Flight Center for a series of ground 

vibration tests. Technicians reinstalled the tailcone aerodynamic fairing. 

Fulton and the 747 crew completed a series of test flights with the Shuttle 

in ferry condition (with its front attachment strut lowered slightly to 

improve the cruise performance of the two mated vehicles) in midNovember. All indications were that the Shuttle could easily be ferried 

atop the 747. On 10 March 1978 the Enterprise left the runway at Dryden 

for the last time. Fulton and his crew ferried the Shuttle to Ellington Air 

Force Base at Houston where, during a weekend stay, it was seen by 

240 000 viewers, creating, in the words of Houston police, “the largest 

traffic jam in Houston’s history.” 

While at Houston, the 747 crew and two other Dryden Shuttle 

project officers received NASA’s Exceptional Service Medal. Nine other 

Johnson and Kennedy center employees also received the Exceptional 

Service Medial, and Donald K. Slayton, project director for the approach 

and landing tests, received NASA’s Outstanding Leadership Medal. On 

13 March the 747-Enterprise departed from Ellington on a short flight to 

Huntsville. Seven thousand NASA and Redstone employees witnessed 

the arrival of the strange pair. The next day, cranes removed the Shuttle 

from the 747 preparatory to installing it in a special test rig at Marshall 

for a series of ground vibration tests simulating the loads a Shuttle would 

experience in flight. l7 

Dryden’s active role in Shuttle had come to an end, until the time in 

the future when another Shuttle would reenter from space over the 

Pacific and glide in for a landing on the Edwards lakebed. 

CONSOLIDATION 

For a while, things returned to normal at Dryden, The Blackbirds 

flew, the TACT continued its investigations, the DFBW F-8 roamed the 

sky. In the few years before the Shuttle Columbia landed at Dryden in 

early 1981, the center had all the appearances of going on much as 

before. A few new programs started up. The center began flight-testing 

the AD- 1, a cooperative venture between the Ames and Dryden centers 

using a specially made twin-jet research airplane with an oblique or 

“scissors” variable sweep wing developed by Robert T. Jones, the American father of the sweptwing. During tests by project pilots Tom McMurtry 

and Fitz Fulton, the little AD- 1 swept its wing up to 60°, but at the most 

250 
Q 

AT THE CROSSROADS 

The Ames-Dryden AD-1 oblique-wing testbed, flying with its adjustable wing in the 

fully swept (60’) position. 

extreme positions the AD - 1’s unpleasant flying characteristics negated 

the potential value of this configuration for future aircraft needing low 

drag and good energy efficiency at transonic speeds.” 

HiMat entered flight testing, gradually working up to high-g remotely piloted manuevering trials. The center borrowed an Air Force 

KC- 135 and outfitted the four-engine tanker-transport with Whitcomb 

winglets, validating the concept of these energy-saving wingtip devices. 

An F- 14 arrived for a joint NASA-Navy program following preliminary 

testing by center personnel at Grumman’s New York test facility. And, 

finally, Dryden began tests with the second of two Bell XV-15 winged 

tilt-rotor convertiplanes as part of a joint V/STOL program with Ames. 

The XV-15 was capable of taking off and landing vertically like a 

helicopter, or of making short takeoffs and landings. In flight the aircraft 

changed into conventional flight with the “prop rotors” functioning as 

propellers. This program marked the beginning of center research in the 

field of rotary-wing aerodynamics, a field NASA had traditionally left to 

Ames and Langley. Dryden seemed stronger than ever, with a balanced 

group of aeronautical research programs and a critical role to play in the 

upcoming orbital flights of the Space Shuttle. This appearance was 

reaffirmed by the center’s second major bout with national publicity, at 

the time of the first orbital flight of the Space Shuttle Columbia in April 

198 1. Columbia landed at Dryden before thousands of onlookers and 

millions on worldwide TV. It was fitting that Columbia arrived at Edwards 

amid the rumbling of its own sonic booms, for Young and Crippen’s 

flight was in the grand tradition of Yeager, Crossfield, Apt, Knight, and 

all the others who had pushed back the frontiers of supersonic and 

hypersonic flight. 

25 1 
a 

ON THE FRONTIER 

Under this tranquil surface, however, the wars of institutional 

assessment raged unabated. And within a month of Young and Crippen’s 

historic flight the outcome was announced by Dr. Alan Lovelace, NASA’s 

acting administrator. Four centers were to be combined: Dryden with 

Ames, and Wallops with Goddard. The smaller centers would retain their 

names (though as “facilities”) while becoming operational elements of the 

larger ones. Dryden and Wallops would be under the overall management and administrative direction of Ames and Goddard, respectively. 

Lovelace emphasized that the consolidations would better focus the 

resources of each center to accomplish what it did best: “The close 

relationship between Ames and Dryden’s efforts in aeronautical programs 

and Wallop’s amd Goddard’s efforts in suborbital programs, as well 

as the unique facility capabilities and the physical proximity of the 

installations provides an opportunity to improve overall program effectiveness through these consolidations.”” 

The consolidations were to be effective as of 1 October 1981. NASA 

Headquarters quickly assembled task and support teams to arrange the 

details. For the California centers, the task team consisted of the Ames 

and Dryden directors (Clarence Syvertson and Ike Gillam); Dr. Walter B. 

Olstad, NASA’s acting administrator for aeronautics and space technology; 

and Jack Boyd, an associate director of Ames and former deputy director 

at Dryden. The support team consisted of the heads of the Ames and 

Dryden directorates affected by the consolidation. By early August, the 

teams had developed a plan for the consolidation, a plan that drew quick 

approval from NASA’s new administrator, James M. Beggs. Dryden would 

become a directorate of Ames. The aeronautical research activities at the 

two locations would be integrated and all staff functions for the two 

centers would be combined; there were to be nei er forced layoffs nor 

relocations as a result of the consolidation. The team estimated that though 

the plan would become effective on 1 October, it would take 30 months to 

implement fully. Selected Ames research aircraft, such as the two XV- 15s 

and the Quiet Short-Haul Research Aircraft (QSRA), would be transferred to Dryden. Ames, in essence, would retain only those aircraft involved in the center’s extensive space sciences and earth resources- remote 

sensing programs, such as the GaZiZeo 11, C-41 Kuiper Airborne Observatory, U-2, and ER-2 aircraft.” 

It was Wellington who wrote, “Nothing except a battle lost can be half 

so melancholy as a battle won.” In the wars of institutional assessment 

that smoldered within NASA, misery afflicted both winners and losers. 

To Dryden’s staff, it seemed a poor reward for years of services 

rendered. But Ames lost an aspect of local research that center had 

always treasured-her on-site flight testing and the Crow’s Landing test 

site. Ames may have gained Dryden, but Dryden expanded its dominion 

over the agency’s flight testing activities. 

252 
'4 c * il 

9- 0 

AT THE CROSSROADS 

The Hugh L. Dryden Flight Research Center shortly after its dedication in 1976. The 

Space Shuttle Enterprise atop its carrier aircraft is at the extreme top. Among other 

aircraft visible are a DC-3 at the top of the apron, a 8-52 carrier aircraft at center, and 

two YF-12s at middle right. 

But was it, in fact, a case of a heartless headquarters forcibly 

consolidating two centers having differing philosophies and orientations? 

Or, was it inevitable, a story that smacked, at least to those with a sense of 

historical cynicism, more of Carthage and Rome? 

In truth, it was an understandable trade-off, given agency history 

over the previous decade. As much as any occurrence is, it was inevitable. 

To explain the decision in other than bland terms of NASA's reorganization pronouncements, it is necessary to consider three questions: Why 

consolidate? Why consolidate Dryden? Why consolidate Dryden with 

Ames? 

NASA's budgetary woes in the post-Apollo era and the rising costs of 

the Space Shuttle dictated a retrenching, a pulling back. It made both 

economic and administrative sense to streamline the structure reporting 

to the NASA administrator by reducing the number of independent 

253 
ON THE FRONTIER 

centers, eliminating wasteful duplication if it existed, and developing 

strong cooperative bonds between organizational elements having related if dissimilar interests in certain areas of aerospace technology. This 

is the doctrine of the hand and glove, or knife and fork. It is a managerial 

trend that has gained great support in recent years, emphasizing teamwork in place of “go it alone” efforts. With the challenges that faced 

NASA in the 197Os, it was certain that some consolidation would take 

place. Although many partisans at Dryden and other centers had feared 

abolishment of their centers, this time that was not seriously considered. 

Both Wallops and Dryden play roles that could not economically be 

assumed by the other centers. Wallops’s long experience with sounding 

rockets make it the lead center for that vehicle. Dryden, of course, has an 

unmatched expertise in flight testing of complex, high-technology aerospace vehicles. In its entire history, it has never received anything but the 

greatest praise from NASA administrators. Dryden and Wallops, then, 

were not candidates for destruction. But they were prime candidates for 

reorganization and consolidation, which leads to the second question, 

Why consolidate Dryden? 

There are several possible answers, all interrelated. The answer 

really involves questions of size, budget, and research. As figure 6 and 

appendix A, B, C, and D indicate, Dryden has always been one of the 

smallest centers. The organization charts indicate a much smaller staff 

with a smaller range of administrative units. It has a much clearer 

organizational mission: “to plan, conduct, analyze, and report on flight 

In 1973 Center Director Lee Scherer announced that his 

goal was “to maintain a position of pre-eminence in the conduct of flight 

research in support of military and civil national needs.”22 The center 

could do this, he believed, by pursuing five objectives: 

1. Flight research of new design concepts and new flight regimes. 

2. Flight research directed toward improving flight safety and/or 

3. Attain recognized national pre-eminence in applied control 

4. Search for improved cost-effective methods of conducting flight 

5. Contribute to the Space Shuttle effort. 

public acceptance. 

technology. 

research. 

Scherer had concluded that over the next decade, the center would find 

its “flight research programs . . . more closely tied to the discipline capabilities of the larger centers with greater consolidation of flight work here.”23 

Dryden was little larger than Wallops in size of its staff, and about as 

specialized in its own way as the east coast facility. Its budget was nowhere 

near as great as the three major OAST centers, Langley, Lewis, and 

Ames, and neither was its range of research facilities. This latter point, 

254 
c 

Personnel 

i: 

AT THE CROSSROADS 

t 

1960 62 E4 66 68 70 72 74 76 78 80 

Year 

Figure 6. Personnel growth and decline for Dryden, Ames, Langley, and Lewis research 

centers, 1 959 - 1 980. 

however, could be misleading. If the wind tunnels at Langley, Ames, and 

Lewis were the most visible symbols of aeronautical research, research 

airplanes were no less important laboratory tools. 

Related to the question of consolidating Dryden was the question of 

its research. The center has always participated in frontier-pushing and 

critically important flight research, though much of that research has 

been in conjunction with other NACA-NASA centers. This tradition goes 

back to the days of the old NACA Muroc Flight Test Unit. The following 

is a list of selected Dryden research activities through the years, together 

with the center that originated the concept. 

Research Area Originating Center 

“Round One” aircraft Langley, USAAF, USN 

“Round TWO” (X- 15) 

“Round Three” (X-20) 

Langley, primarily 

Langley, USAF 

Lifting bodies Ames, Langley, USAF 

255 
ON THE FRONTIER 

Reseurch Area Originating Center 

Paresev (paraglider research 

XB-70A Langley, Ames, NASA OART 

YF- 12 

F-8 SCW-F- 11 1 TACT 

AD- 1 oblique wing Ames 

HiMAT NASA OAST, USAF 

XV-15 Ames, Army 

Space Shuttle Johnson, Marshall 

In these projects DFRC has been charged with working with a concept in a particularly important way. For example, Whitcomb developed 

the supercritical wing, DFRC demonstrated it. Ames and Langley conceived the lifting bodies, DFRC validated them. DFRC has also shown 

great initiative in starting critically needed flight research-such as the 

proof-of-concept flight testing of the lifting body concept and the Rogallo 

concept-but DFRC has not been able to compete with either Ames or 

Langley in developing theoretical concepts. DFRC excels in what it was 

intended to be: a flight test center for the entire agency, with specialized 

strengths in high-speed flight. Dryden has made strong contributions in 

simulation (as in the LLRV-LLTV program) and with such developments 

as the remotely piloted research vehicles and the center’s digital fly-bywire flight-control testbeds. It might be said that Dryden has been the 

diligent craftsman, testing out the ideas of others and improving on 

them. 

Dryden has always shown a strong tendency to work project-byproject with another NACA-NASA center, especially Langley and Ames. 

Flight research and research on the ground should be closely related, and 

there has to be a partnership between the flight-test aircraft and the wind 

tunnel. Dryden, as viewed from Headquarters, was ripe for consolidation. 

And that meant with one of the three major OAST centers, Langley, 

Ames, or Lewis. 

Which brings this discussion to the last question, Why consolidate 

Dryden with Ames? This question is perhaps the easiest to answer. Dryden was spawned by Langley, as were most of the NACA-NASA centers. 

Under NACA, the Muroc-Edwards facility did not seem the small anomaly that it became within the larger NASA. Even in the early years, 

however, administration of the Muroc center proved awkward, and there 

were some feelings of unease on the part of the Ames administrators as 

Space Task Group (Johnson 

vehicle) forerunner) 

Ames, USAF, NASA OART 

Langley 

256 
AT THE CROSSROADS 

the Langley offshoot grew up in their backyard. The Muroc unit, soon to 

become the HSFS, quickly developed ties with Ames; following the severance of its final links with Langley’s administration in 1954, rapport 

between the California centers became very close. Lewis never really 

counted; Lewis was an engine research center, so Dryden had at best 

minimal contact with it. 

Dryden worked principally with Ames and Langley, In the 1960s, 

with Ames studying lifting bodies and programs such as the SST and 

advanced supersonic aircraft, the connections between Dryden and Ames 

tightened even further. There were some differences between them: 

Dryden usually emphasized high speed, Ames usually low speed with 

V/STOL. But the differences were complementary, not mutually destructive or exclusive. Except for Dryden, Ames was the smallest of the QAST 

centers. Their combination would tend to equalize the size of the remaining centers. Geography certainly favored the alliance. Separated by only a 

few hundred kilometers, Ames and its wind tunnels and analytical 

branches naturally could complement Dryden and its real-world flight 

testing just down the road. 

Some of the history-makers: DFRC’s research pilot stafl, including (left to right) Milt 

Thompson (later DFRC associate director), Fitz Fulton, Bruce Peterson (later chief of 

safety), Don Mallick, John Manke, Einar Enevoldson, Bill Dana, and Tom McMurtry. 

Not shown are Gary Krier, Steve Ishmael, and the late Mike Swann. 

257 
ON THE FRONTIER 

As popularly interpreted, Dryden “lost” to Ames. But in fact, both 

centers gained much. It was a good ground research-flight research 

mix. Gillam, in discussions at Headquarters, got the best possible deal for 

his center. Ames lost a large portion of its own flight research activities 

and aircraft to Dryden; Dryden’s staff-always happier with hands-on 

research than administration anyway-could luxuriate in having traded 

administrative burden for more aircraft and time to work on them. 

IN RETROSPECT 

It would not be fair to Dryden, Ames, or NASA to close on a 

downbeat note such as: 

HUGH L. DRYDEN FLIGHT RESEARCH CENTER 

1946- 1981 

R.I.P. 

Dryden is very much alive and well. It has merely undergone a change of 

status. Indeed, elimination of Dryden as a separate independent NASA 

center equal with Langley, Ames, and Lewis merely eliminated a fiction. 

Dryden was always the smallest, always the most specialized, always the 

service center. The reorganization did not reflect on the quality or level 

of work of the center and its people. Indeed, Dryden has always enjoyed 

an excellent reputation within and outside of NASA, and the agency 

foresees a broad range of programs and tasks for DFRC in the years 

ahead. 

Hugh Latimer Dryden, a man who grew up with the airplane, was 

fond of remarking that the most important tool in aeronautical research 

is the human mind. The story of his center is not at an end. The story will 

go on as long as there are those who dream dreams and those who seek to 

make dreams a reality. 

258 
* a 

Appendixes 

A Note on Sources, Source Notes 

Index 
D c 
Appendix A 

Organization Charts, 1948 - 198 1 

A WORD ABOUT FRC/DFRC ORGANIZATION 

Unlike other field centers under the NASA Headquarters OAKT/OAST 

office, Flight Research Center, later Dryden Flight Research Center, has always 

been small, with a single overriding purpose: flight research using advanced 

aerospace research vehicles. Thus changes of major significance in its administrative organization have been few. The 1948 chart reflects the close identity of the 

Muroc Flight Test Unit with specific aircraft programs. As the unit expanded to 

station and eventually center size, gaining autonomy along the way, its administrative organization of necessity became broader and more in line with that of 

other NACNNASA research facilities. As indicated in chapters 3 and 6, the 

center's organization remained largely unchanged in 1960 from the days of the 

station in 1954; there was strong continuity from the period of HSFS Director 

Walter C. Williams to the period of FRC Director Paul F. Bikle. Organization 

charts for 1960 through 1966 also reflect continuity. Even into the 1970s, under 

Director Lee R. Scherer (1975 chart), FRC organization remained strongly 

oriented along previous lines, mainly structured around four key directorates: 

Research, Data Systems, Flight Operations, and Administration. Under Center 

Director David Scott (1976 chart) came the first significant departure from the 

previous structural framework, with the addition of two new directorates, 

Aeronautical Projects and Shuttle Operations. 

On the eve of consolidation with Ames Research Center, DFRC's structure 

showed further changes introduced by Director Isaac Gillam. By 1979, the 

traditional directorate structure had disappeared, replaced by a more centralized and integrated one built around a strong executive-staff support network 

and three major directorates: Engineering, Flight Operations and Support, and 

Administration (see chart for 1979). These changes reflected the wishes of 

NASA as a whole to consolidate the functions of the centers both within the 

contexts of the centers themselves and that of the agency as a whole. These same 

wishes were responsible for eventual decision to merge DFRC and ARC into a 

single operating administrative unit (see chapter 1 1). 

26 I 
c 

ON THE FRONTIER 

262 
ORGANIZATION CHARTS 

n 

263 
P 

ON THE FRONTIER 

264 
4 

ORGANIZATION CHARTS 

-0 

> n 

265 
ON THE FRONTIER 

266 
ORGANIZATION CHARTS 

A- - 
"- 

ON THE FRONTIER 

d d 

268 
P 4 $3 b P 

c 

C 

m Y C 

.- 

r 

E 0 

- 

-L 

ORGANIZATION CHARTS 

-I 

269 
ON THE FRONTIER 

1 

270 
ORGANIZATION CHARTS 

I Liaison Office I I 

I----- I USN Liaison Office a R. Johannes 

I. Gillam 

1 r---. 

Hugh L. Dryden Flight Research Center 

National Aeronautics and Space Administration 

August 1981 

Associate Director 

(Technical) 

M. Thompson 

R. Waite 

E. Videan 

Technology 

Utilization 

I 

Administration Engineering Flight Operations 

Directorate and Support Directorate Directorate 

K. Hodge L. Stern G. Layton J. Manke 

J. McTigue I I I 

Dynamics and 

Control Division 

Engineering 

271 

Appendix B 

Personnel Summary for FRCIDFRC, Other OART/OAST 

Centers, and NASA as a Whole 

Year FRC/DFRC AMES RC Langley RC Lewis RC NASA Total 

1959 

1960 

1961 

1962 

1963 

1964 

1965 

1966 

1967 

1968 

1969 

1970 

1971 

1972 

1973 

1974 

1975 

1976 

1977 

1978 

1979 

1980d 

340 

408 

447 

538 

616 

619 

669 

662 

642 

622 

60 1 

583 

579 

539 

509 

53 1 

544 

566 

546 

514 

498 

499 

1464 

1421 

1471 

1658 

21 16 

2204 

2270 

2310 

2264 

2197 

2117 

2033 

1968 

1844 

1740 

1776 

1754 

1724 

1645 

1691 

1713 

1713 

3624 

3203 

3338 

3894 

4220 

4330 

437 1 

4485 

4405 

4219 

4087 

3970 

3830 

3592 

3389 

3504 

3472 

3407 

3207 

3167 

3125 

3094 

2809 

2722 

2773 

3800 

4697 

4859 

4897 

5047 

4956 

4583 

4399 

4240 

4083 

3866 

3368 

3172 

3181 

3168 

3061 

2964 

2907 

290 1 

9 235 

10 232 

17 471 

23 686 

29 934 

32 499 

34 049 

35 708 

35 860 

34 641 

33 929 

32 548 

30 506 

28 382 

26 777 

26 007 

25 638 

25 426 

24 188 

23 779 

23 360 

~

23 470 - 

dAs of 30 September 1980. 

SOURCE: NASA Office of Management Operations data. 

273 

d s n 

Appendix C 

HS FS/FRC/D FRC Technical Facilities 

Obligations for Facilities Construction at FRCIDFRC 

Year Amount 

(in millions) 

1959 

1960 

1961 

1962 

1963 

1964 

1965 

1966 

1967 

1968 

1969 

1970 

1971 

1972 

1973 

1974 

1975 

1976 

1977 

1978 

1979 

1980 (as of 30 Sept.) 

$0 

1.8 

0 

0 

1.8 

2.5 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

.9 

.8 

.4 

0 

0 

NO~E: It is worth remembering that the FRC/DFRC's greatest research resources have been the 

experimental aircraft themselves, which are analogous to the wind tunnels, shock tubes, etc., at other 

centers. DFRC's need for specialized facilities on the ground for testing and research has thus 

traditionally been far less than other NACA-NASA centers. In a 1973 OAST research evaluation, 

DFRC's major facilities listed only 1 ground laboratory (for high-temperature loads calibration) and 

10 specialized flight research aircraft, an appropriate example of the importance attached to research aircraft. 

SOURCE: NASA Office of Management Operations data. 

2'75 
* 

ON THE FRONTIER 

Major HSFSIFRCIDFRC Technical Facilities 

(Not including specialized flight research 

aircraft, for which see appendix E.) 

Facility Year cost Research 

Built (thousands) 

Air Vehicle Flight 1956 

Simulation Facility 

High Range Tracking Net 

Edwards Station 1958 

Ely Station 1958 

Beatty Station 1958 

Voice Communications 1963 

Facility 

Runway Noise Acquisition 1964 

High Temperature Loads 1966 

System 

Calibration Laboratory 

$68 

4244 

2322 

2122 

68 

127 

1712 

Flight planning, pilot 

training, systems analysis, 

vehicle handling qualities, 

and flight-data analysis. 

Analog and digital trajectory 

data, telemetry reception and 

processing and voice 

communications for real-time 

and postflight analysis in support 

of X- 15 and other 

high-performance aircraft 

testing. 

Voice communications for 

real-time support of highperformance aircraft testing. 

Determination of aircraft 

takeoff and landing noise levels. 

Heating, loading, and 

calibration of aircraft and 

components. ~~ 

SOURCE: NASA Technical Facilities Catalog (Washington, D.C.: NASA, March 1967), I, section 3. 

276 
Appendix D 

Authorized Funding for Research 

and Program Management 

at FRC/DFRC, Other OARTIOAST Centers, and NASA 

(in millions) 

Year FRC/DFRC Ames RC Langley RC Lewis RC NASA Total 

1959 

1960 

1961 

1962 

1963 

1964 

1965 

1966 

1967 

1968 

1969 

1970 

1971 

1972 

1973 

1974 

1975 

1976 

1977 

1978 

1979 

1980" 

$ 3.3 

4.3 

5.1 

7.2 

7.5 

9.4 

10.5 

9.4 

9.5 

9.5 

9.7 

10.3 

11.1 

11.7 

11.6 

12.2 

13.2 

14.5 

17.3 

18.2 

19.1 

20.4 

$16.3 

17.8 

19.9 

22.9 

25.6 

29.9 

31.8 

33.2 

33.8 

33.8 

34.0 

37.6 

40.6 

42.2 

42.4 

46.4 

48.6 

50.9 

53.0 

57.8 

62.7 

67.4 

$ 31.4 

33.0 

39.1 

46.6 

51.8 

52.1 

59.0 

63.5 

64.3 

62.2 

63.0 

69.8 

75.3 

80.2 

78.6 

83.8 

88.6 

93.1 

95.2 

102.0 

106.6 

114.0 

$27.8 

31.2 

35.8 

45.2 

53.4 

61.5 

69.3 

66.4 

66.3 

66.2 

67.9 

73.9 

78.0 

82.5 

81.2 

79.8 

80.3 

80.7 

83.6 

84.9 

87.5 

94.8 

$ 87.8 

118.6 

222.7 

315.6 

438.7 

496.8 

623.3 

61 1.2 

646.6 

639.3 

648.0 

702.2 

730.2 

732.3 

721.8 

744.0 

764.7 

792.3 

844.4 

889.5 

933.8 

996.0 

"As of 30 September 1980. 

SOURCE NASA Office of Management Operations data. 

277 
w a 
b n i" 

Appendix E 

HSFS/FRC/DFRC Research Aircraft, 194'7 - 1980 

Aircraft operated by NACA and NASA for NACA and NASA testing. Times 

refer only to period actually operated by NACA or NASA at the center. 

1. Piloted Experimental Research Aircraft 

Aircraft - Serial NACNNASA 

Number Code Remarks 

Bell XS-1 #2 

Bell X- 1A 

Bell X- 1B 

Bell X- 1E 

Douglas X-3 

Northrop X-4 #1 

Northrop X-4 #2 

Bell X-5 #1 

Convair XF-92A 

Douglas D-558- 1 #1 

Douglas D-558- 1 #2 

Douglas D-558- 1 #3 

Douglas D-558-2 #1 

Douglas D-558-2 #2 

Douglas D-558-2 #3 

North American X-15 #1 

North American X- 15 #2 

North American X- 15 #3 

46-063 

48- 1384 

48- 1385 

46-063 

49 - 2892 

46-676 

46-677 

50- 1838 

46-682 

37970 

3797 1 

37972 

37973 

37974 

37975 

56-6670 

56-6671 

56-6672 

- 

- 

- 

- 

- 

- 

- 

- 

- 

NACA 140 

NACA 141 

NACA 142 

NACA 143 

NACA 144 

NACA 145 

- 

- 

- 

Flown 1947-1951. 

Flown 1955, destroyed. 

Flown 1956- 1958. 

Rebuilt from XS-1 #2, 

flown 1955-1958. 

Flown 1954-1956. 

Acquired 1950, but used 

only for spares support. 

Flown 1950- 1954. 

Flown 1952- 1955. 

Flown 1953. 

Acquired 1949, for spares. 

Flown 1948, destroyed. 

Flown 1949-1953. 

Flown 1956 after storage. 

Flown 1949- 1956. 

Flown 1950- 1956. 

Flown 1960- 1968. 

Damaged in landing 

accident in 1962, rebuilt as 

X- 15A-2. Retired 1968. 

Destroyed in 1967. 

279 
ON THE FRONTIER 

1. Piloted Experimental Research Aircrafl, Continued 

Aircraft Serial NACAINASA 

Number Code Remarks 

NASA FRC Paresev N-9765Z - Flown 1962- 1964. 

NASA FRC M2-F1 N-86652 - Flown 1963-1964. 

Northrop M2 - F2, M2 - F3 - NASA 803 Flown 1966- 1967. 

Damaged in landing accident. Rebuilt as M2-F3, 

flown, retired in 1972. 

Northrop HL- 10 - NASA 804 Flown 1966- 1970. 

Martin X-24A, X-24B 66-13551 - Flown 1969-1971. Rebuilt 

as X-24B, flown 

1973- 1975. 

LLRV #1 

LLRV #2 

- _. Flown 1964- 1966; sent 

to JSC; crashed 1968. 

- - Flown 1967; sent to JSC, 

returned to FRC; retired. 

North American XB-70A #I 62-0001 - Flown 1967- 1969. 

Lockheed YF- 12A 60-6935 DFRC 935d Flown 1969- 1978. 

Lockheed YF- 12A 60-0936 - Flown 1970, destroyed 

Lockheed YF- 12C 60-0937 DFRC 937" Flown 1972- 1979. 

Vought TF-SA SCW 141353 NASA 8 10 Flown 197 1 - 1973. 

Vought F-8C DFBW 145546 NASA 802 Flown 1972; ongoing. 

Gen. Dynamics F- 11 1A TACT 63-9778 - Flown 1972; ongoing. 

Gen. Dynamics F- 11 1E IPCS 67-01 15 - Flown 1974- 1976. 

(Air Force flight). 

Boeing 747 N-905NA NASA 905 Flown 1974; ongoing. 

Shuttle ferry aircraft. 

Boeing NKC- 135A 55-3129 - Flown 1979- 1980, winglets. 

Lockheed Jetstar N-814NA NASA 814 GPAS, flown 1965; ongoing. 

Ames-Dryden AD- 1 N-805NA NASA 805 Flown 1979-1982. 

"Informal code; NASA 900 series assigned to Johnson Space Center. 

280 
* * e e c 

RESEARCH AIRCRAFT 

2. Remotely Piloted Research Vehicles - - 

Aircraft Serial Number NACAINASA Code Remarks 

“Mother” - - Radio-controlled model 

flown to launch other 

models. Flown 

1962- 1968. 

Hyper 111 - - Launched from helicopter. One flight in 

1969. 

Piper PA-30 N-808NA NASA 808 Flown as RPRV in 1971. 

F- 15 RPRV#l and #2 - - Launched from B-52; 

first flown 1973, one 

flying as DFRC Spin 

Research Vehicle (SRV). 

HiMAT Flown 1979; ongoing. #I and #2 - - 

Mini - Flown 1975; ongoing. -Sniffer I, 11, 111 - 

DAST - - Flight loads alleviation 

testbed; destroyed 1980. 

3. Military Models Flown on Experimental Research Flights 

Aircraft Serial NACA/NASA 

Number Code Remarks 

North American TF-5 1D 

Republic YF-84A 

Republic YF-84A 

Republic YRF-84F 

North Arnerican’F-86F 

North American F- lOOA 

North American F- lOOC 

North American F- IOOC 

North American JF- lOOC 

44 -84958 

45-59488 

45 - 59490 

51-1828 

52 -5426 

52-5778 

53-1712 

53- 1717 

53- 1709 

NACA 148 

- 

NACA 134 

NACA 154 

- 

- 

- 

- 

- 

Dives to 0.8 mach; also used 

for proficiency flights. 

Flown 1950- 1954, primarily 

proficiency. 

Flown 1949-1954; vortex 

generator research. 

Flown 1954- 1956; pitch-up 

research. 

Flown 1954 for AF pitch-up 

research. 

Flown 1954- 1960. 

Flown 1956- 1957. 

Flown 1957-1961. 

Flown 1960- 1964; variablestability studies. Transferred 

to FRC from Ames. 

28 1 
ON THE FRONTIER 

3. Military Models Flown on Experimental Research Flights, Continued 

Aircraft Serial NACAINASA 

Number Code Remarks 

McDonnell F-1OIA 53-2432 

Convair YF- 102 53- 1785 

Convair F- 102A 54- 1374 

Lockheed YF- 104A 55-296 1 

Lockheed F- 104A 56-734 

Lockheed F- 104A 56-749 

Lockheed F- 104B 57-1303 

Lockheed F- 104N N-O11NA 

Lockheed F- 104N N-O12NA 

Lockheed F- 104N N-Ol3NA 

Lockheed F- 104A 56-790 

Lockheed TF- 104G - 

Lockheed TF- 104G - 

Lockheed F- 104G - 

Republic F- 105B 54- 102 

North American YF-lO7A 55-51 18 

North American YF-107A 55-5120 

Gen. Dynamics F- 11 1A 

Gen. Dynamics F- 11 1A 

McDonnell F-4A 145313 

63-9771 

63-9777 

Douglas F5D- 1 139208A 

- 

- 

- 

NASA 818 

- 

- 

NASA 819 

NASA 01 1 

(later 81 1) 

NASA 012 

(later 812) 

NASA 013 

NASA 820 

NASA 824 

NASA 825 

NASA 826 

- 

- 

- 

._. 

- 

- 

NASA 212 

Flown 1956; for pilot 

familiarization. 

Flown 1954- 1958. 

Flown 1956- 1959. 

Flown 1956- 1975. 

Flown 1957- 1961. 

Flow: 1959- 1962, destroyed. 

Flown 1959- 1978. 2-seat. 

Flown 1963-on. Special 

F- 104 version for FRC. 

F- 104 version for FRC. 

F- 104 version for FRC. 

Destroyed in mid-air collision, 

1966. 

Replacement for 0 13. 

Ex Luftwaffe; received 

in 1975. 

Ex Luftwaffe; received in 

1975. 

Ex Luftwafle; received in 

1975. 

Flown 1959; familiarization. 

Flown 1957-1958; grounded 

for spares support. 

Flown 1958- 1959; 

destroyed. 

Flown 1967-1971. 

Flown 1969-1971. 

Flown 1966- 1967; damaged 

in flight, retired. 

Flown 1961. Transferred to 

Ames in 1963 for SST 

studies. 

282 
x d * t M c c 4 

RESEARCH AIRCRAFT 

3. Military Models Flown on Experimental Research Flights, Continued 

Aircraft Serial NACAINASA 

Number Code Remarks 

Douglas F5D- 1 142350 NASA 213 Flown 1961-1970. 

Northrop YF- 17 70- 1569 - Flown 1976. 

McDonnell Douglas F- 15A 71 -0281 - Flown 1975; ongoing. 

McDonnell Douglas F-15A 71-0287 - Flown 1975; ongoing. 

Grumman F- 14A 157991 DFRC 991" Flown 1979; ongoing. 

North American A-5A 147858 - Flown in 1963; SST work. 

Boeing JTB - 29A 45-2 1800 - X- 1 series mothership, 

Boeing B-29A 45-21787 NACA 137 33-558-2 mothership, flown 

Boeing B-47A 49-1900 NACA 150 Flown 1953-1957. 

Boeing KC- 135A (unknown) - Flown 1957; damaged in 

mid-air collision, retired. 

Boeing KC- 135A 55 -3 124 - Replacement; flown 1958. 

Boeing NB-52B 52-008 DFRC 008" Mothership; ongoing. 

"Unofficial NASA code. 

!down 1955-1958. 

1951 - 1959. 

4. Miscellaneous Models Flown on Experimental Research Flights 

Mostly light aircraft flown as part of an FRC 

general-aviation safety survey, 1964- 1966. Piper PA-30 and 

Aero Commander were exceptions. 

Aircraft Serial Number NACAINASA Remarks 

Cessna 0- 1A (L- 19A) 51 -2220 - Flown 1962. 

Cessna TO-IA (L-19G) ??-4128 - 

Beech Debonair N -4307 - 

Beech (?) N5849K - Flown 1965. 

Cessna 3 10 8199M16-1 - 

Cessna 2 10 N-910V - Flown 1965. 

Flown 1965. 

Flown 1966. 

Flown 1963- 1964. 

Flown 1964- 1965. 

Flown 1964- 1965. 

Piper Apache N-4383P - 

Piper (?) N-7845Y - 

283 
ON THE FRONTIER 

4. Miscellaneous Models Flown on Experimental Research Flights, Continued 

Aircraft Serial Number NACNNASA Remarks 

Piper PA-30 N-8351Y NASA 808 Flown 1967, later as RPRV, 

(later and then as general misN -808NA) sion support aircraft. 

(later 

Aero Commander N-6297X NASA 80 1 Flown 1963; ongoing. 

N - 80 1 N A) 

Bell XV- 15 #I N-702NA NASA 702" Flown 1981; ongoing. 

Bell XV-15 #2 N-703NA NASA 703" Flown 1980; ongoing. 

dNASA-Army tilt-rotor research program mdndged by Ames Research Center. 

284 
Appendix F 

X- 1 Program Flight Chronology, 1946- 1958 

This chronology covers all the flights of X- 1 series aircraft built and flown. NACA 

operated the X- 1 #2, X- 1 A, X- lB, and X- 1E (the rebuilt X- 1 #2). In the interest of 

completeness, and because of the close NACA- Air Force-Bell relationship in the entire 

program, flights of the other aircraft are also listed. The X-1 series aircrafi were airlaunched from modified Boeing B-29 or B-50 Superfortress bombers. 

1. XS-1 #I ( X- 1 -l), Serial 46-062, Flights 

Date Remarks ~ 

Bell Contractor Flights 

19 Jan. 1946 

5 Feb. 

11 Feb. 

19 Feb. 

25 Feb. 

26 Feb. 

26 Feb. 

6 Mar. 

10Apr. 1947 

11 Apr. 

29 Apr. 

30 Apr. 

5 May 

15 May 

At Pinecastle AAF, Florida 

Bell flight 1, Jack Woolams, pilot. Familiarization. 

Bell flight 2, Woolams. 

Bell flight 3, Woolams. 

Bell flight 4, Woolams. Gear retracted, left wing 

damaged. 

Bell flight 5, Woolams. Nosewheel retracted on 

landing runout. Landing-gear door damaged. 

Bell flight 6, Woolams. Static directional stability 

investigation. 

Bell flight 7, Woolams. Longitudinal and directional stability investigation. 

Bell flight 8, Woolams. Dynamic stability check. 

Bell flight 9, Woolams. Rate of roll investigation. 

Bell flight 10, Woolams. Static longitudinal stability 

investigation. 

At Muroc Dry Lake, California 

Bell flight 1 1, Chalmers Goodlin. Glide flight and 

stall check. 

Bell flight 12, Goodlin. Nosewheel damaged. First 

powered flight of XS- 1 # 1 aircraft. 

Bell flight 13, Goodlin. Handling qualities check. 

Bell flight 14, Goodlin. Same as flight 13. 

Bell flight 15, Goodlin. Same as flight 13. 

Bell flight 16, Goodlin. Buffet-boundary investigation. Aileron-damper malfunction. 

285 
ON THE FRONTIER 

1. XS-1 #I ( X- 1 -l)? Serial 46-062, Flights, Continued 

Date Remarks 

19 May 1947 

21 May 

5 June 

Air Force Flights 

6 Aug. 1947 

7 Aug. 

8 Aug. 

29 Aug. 

4 Sept. 

8 Sept. 

10 Sept. 

12 Sept. 

3 Oct. 

8 Oct. 

10 Oct. 

14 Oct. 

27 Oct. 

28 Oct. 

29 Oct. 

31 Oct. 

3 Nov. 

4 Nov. 

6 Nov. 

16 Jan. 1948 

22 Jan. 

30 Jan. 

24 Feb. 

11 Mar. 

26 Mar. 

Bell flight 17, Goodlin. Buffet-boundary investigaBell flight 18, Goodlin. Same as flight 17. 

Bell flight 19, Goodlin. Demonstration flight for 

tion. 

Aviation Writers Association. 

AF glide flight 1, Capt. Charles E. Yeager. Pilot 

AF glide flight 2, Yeager. Same as flight 1. 

AF glide flight 3, YeageI. Same as flight 1. 

AF powered flight 1, Yeager. Mach 0.85. 

AF flight 2, Yeager. About mach 0.89. Telemeter 

failure required repeat of this flight. 

AF flight 3, Yeager. Repeat of flight 2. 

AF flight 4, Yeager. Mach 0.91. Stability and 

control investigation. 

AF flight 5, Yeager. Mach 0.92. Check of elevator 

and stabilizer effectiveness. Also buffet investigation. 

familiarization. 

AF flight 6, Yeager. Same as flight 5. 

AF flight 7, Yeager. Airspeed calibration flight. 

Plane attained mach 0.925. 

AF flight 8, Yeager. Stability and control investigation. Plane attained mach 0.997. 

AF flight 9, Yeager. World’s first supersonic flight 

by a manned aircraft. XS- 1 #1 attained mach 

1.06 at 43,000 ft., approximately 700 mph. 

AF flight 10, Yeager. Electric power failure. No 

rocket. 

AF flight 11, Yeager. Telemeter failure. 

AF flight 12, Yeager. Repeat of flight 11. 

AF flight 13, Yeager. 

AF flight 14, Yeager. 

AF flight 15, Yeager. 

AF flight 16, Yeager. Mach 1.35 at 48 600 ft. 

AF flight 17, Yeager. Airspeed calibration. 

AF flight 18, Yeager. Pressure distribution survey. 

AF flight 19, Yeager. Same as flight 18. Mach 1.1. 

AF flight 20, Capt. James T. Fitzgerald, Jr. Engine 

fire after launch forced jettisoning of propellants; completed as a glide flight. 

AF flight 21, Yeager. Attained mach 1.25 in dive. 

AF flight 22, Yeager. Attained mach 1.45 at 40 130 

ft (957 mph) during dive. Fastest flight ever 

made in original XS- 1 aircraft. 

Mach 0.9. 

Mach 1.2. 

286 
X-1 FLIGHTS 

1. XS-1 #I (X-1 -l), Serial 46-062, Flights, Continued 

Date Remarks 

31 Mar. 1948 

6 Apr. 

7 Apr. 

AF flight 23, Yeager. Engine shutdown after launch. 

Propellants jettisoned, completed as glide flight. 

AF flight 24, Fitzgerald. Pilot-check flight. Mach 

1.1, during 4-cylinder run at 4 1 000 ft. 

AF flight 25, Maj. Gustav E. Lundquist. Glide 

flight only. 

AF flight 26, Fitzgerald. Familiarization flight. 

AF flight 27, Lundquist. Powered pilot-check flight. 

AF flight 28, Lundquist. Pressure distribution survey. Only cylinders 2 and 4 ignited. 

AF flight 29, Fitzgerald. Aborted because of inconsistent rocket operation. Reached mach 0.9. 

AF flight 30, Lundquist. Pressure distribution survey. Attained mach 1.18. 

AF flight 31, Fitzgerald. Same as flight 30. Mach 

1.15. 

AF flight 32, Lundquist. Stability and control and 

buffeting investigation. Mach 0.92 

AF flight 33, Fitzgerald. Buffet investigation, wing 

and tail loads. Mach 1.08. 

AF flight 34, Yeager. Same as flight 33. Mach 1.05. 

AF flight 35, Lundquist. Left main gear door 

opened in flight. Nosewheel collapsed on landing. 

AF flight 36, Yeager. Handling qualities and wing 

and tail loads at mach 1. 

AF flight 37, Yeager. Same as flight 36. 

AF flight 38, Yeager. Wing and tail loads during 

supersonic flight at high altitudes. Mach 1.09. 

AF flight 39, Yeager. Rocket takeoff from the 

ground. 

AF flight 40, Capt. Jack Ridley, pilot. Familiarization flight. Mach 1.23 at 35 000 ft. Small engine 

fire due to loose igniter. 

AF flight 41, Col. Albert Boyd, pilot. Familiarization flight. Inflight engine fire and shutdown. 

AF flight 42, Maj. Frank Everest, Familiarization 

flight. Mach 1.22 at 40 000 ft. 

AF flight 43, Everest. Check of pressure suit for 

altitude operation. Mach 1.24 at 48 000 ft. Rocket 

fire and automatic engine shEtdown. 

transonic speeds. Mach 1.1 at 40 000 ft. 

cylinders fired. 

faulty engine ignition plug. 

jamming rudder. Everest landed safely. 

66 846-ft altitude. 

9 Apr. 

16 Apr. 

26 Apr. 

29 Apr. 

4 May 

21 May 

25 May 

26 May 

3 June 

1 Dec. 

13 Dec. 

23 Dec. 

5 Jan. 1949 

11 Mar. 

16 Mar. 

21 Mar. 

25 Mar. 

14 Apr. 

19 Apr. 

2 May 

5 May 

25 Jul. 

AF flight 44, Ridley. Accelerated stall check at 

AF flight 45, Everest, Altitude attempt. Only 2 

AF flight 46, Yeager. Partial engine malfunction, 

AF flight 47, Everest. Engine chamber exploded, 

AF flight 48, Everest. Altitude attempt. Attained 

287 
ON THE FRONTIER 

1. X S - I #I ( X-I -I), Serial 46-062, Flights, Continued 

Date Remarks 

8 Aug. 1949 

25 Aug. 

6 Oct. 

26 Oct. 

29 Nov. 

2 Dec. 

21 Feb. 1950 

26 Apr. 

5 May 

8 May 

12 May 

AF flight 49, Everest. Altitude attempt. Attained 

7 1 902-ft altitude. 

AF flight 50, Everest. First use of partial pressure 

suit to save life of pilot during flight at high 

altitude. X- 1 # 1 lost cockpit pressurizationabout 

69 000 ft. Everest made safe emergency descent. 

AF flight 51, Lt. Col. Patrick Fleming, pilot. Pilot 

familiarization; attained mach 1.2. 

AF flight 52, Maj. Richard L. Johnson, pilot. Pilot 

familiarization. 

AF flight 53, Everest. High-altitude wing-and-tailloads investigation. 

AF flight 54, Everest. Same as flight 53. 

AF flight 55, Everest. Wing-and-tail-loads investiAF flight 56, Yeager. Lateral stability and control 

AF flight 57, Ridley. Buffeting, wing and tail loads. 

AF flight 58, Ridley. Same as flight 57. 

AF flight 59, Yeager. Last flight of X- 1 #l. Flight 

made for camera footage for motion picture Jet 

Pilot. Aircraft subsequently retired and presented 

to the Smithsonian Institution. 

gation. 

investigation. 

2. X S - I #2 ( X-I -2), Serial 46-063, Flights 

Date Remarks 

Bell Contractor Flights 

11 Oct. 1946 

14 Oct. 

17 Oct. 

2 Dec. 

9 Dec. 

20 Dec. 

8 Jan. 1947 

17 Jan. 

22 Jan. 

Bell flight 1, Chalmers Goodlin, pilot. Glide flight, 

Bell flight 2, Goodlin. Glide flight. 

Bell flight 3, Goodlin. Glide flight, stall check. 

Bell flight 4, Goodlin. Glide flight, check of fueljettison system. 

Bell flight 5, Goodlin. First XS- 1 powered flight. 

Mach 0.79 at 35 000 ft. Minor engine fire. 

Bell flight 6, Goodlin. Familiarization powered 

flight. 

Bell flight 7, Goodlin. Buffet boundary investigation. Mach 0.80 at 35 000 ft. 

Bell flight 8, Goodlin. Same as flight 7. Full-power 

climb. Plane reached mach 0.82. 

Bell flight 9, Goodlin. Same as flight 8. Telemetry 

failure. 

pilot familiarization. 

288 
X-1 FLIGHTS 

2. X S- 1 #2 (X-1-2), Serial 46-063, Flights, Continued 

Date Remarks 

23 Jan. 1947 

30 Jan. 

31 Jan. 

5 Feb. 

7 Feb. 

19 Feb. 

21 Feb. 

22 May 

29 May 

NACA Flights 

25 Sept. 1947 

21 Oct. 

16 Dec. 

17 Dec. 

6 Jan. 1948 

8 Jan. 

9 Jan. 

15 Jan. 

21 Jan. 

23 Jan. 

27 Jan. 

4 Mar. 

10 Mar. 

7 

22 Mar. 

Bell flight 10, Goodlin. Same as flight 8. 

Bell flight 11, Goodlin. Accelerated stalls. Partial 

power due to faulty engine igniters. Mach 0.75. 

Bell flight 12, Goodlin. Same as flight 7. Mach 0.7. 

Bell flight 13, Goodlin. Machmeter calibration. 

Bell flight 14, Goodlin. Same as flight 7. 

Bell flight 15, Goodlin. Accelerated stalls. 

Bell flight 16, Goodlin. Flight aborted after drop 

because of low engine-chamber pressure. 

Bell flight 17, Alvin M. Johnston. Pilot familiarization flight. Mach 0.72, 8 g pullout. 

Bell flight 18, Goodlin. Airspeed calibration flight 

to mach 0.72. End of Bell contractor program. 

NACA acceptance flight. Capt. Charles E. Yeager. 

Number 4 cylinder burned out. 

NACA glide-familiarization flight for NACA pilot 

Herbert H. Hoover. Stall check. Nosewheel collapsed on landing. 

NACA powered flight 1, Hoover. Familiarization. 

Mach 0.84. No telemetry record. 

NACA flight 2, Hoover. Same as flight 1. Mach 0.8. 

NACA flight 3, Hoover. Turns and pull-ups to 

buffet. Mach 0.74. 

NACA flight 4, Hoover. Turns and pull-ups to 

buffet. Mach 0.83. 

NACA flight 5, Howard C. Lilly. Pilot familiarization. 

NACA flight 6, Lilly. Turns and pull-ups to buffet. 

Sideslips. Mach 0.76. 

NACA flight 7, Hoover. Stabilizer effectiveness investigation. Mach 0.82 at 29 000 ft. 

NACA flight 8, Hoover. Attempted high-speed 

run aborted at mach 0.83, drop in chamber 

pressure. 

NACA flight 9, Hoover. High-speed run to mach 

0.925 at 38 000 ft. Cylinders 2 and 3 failed to 

fire. 

NACA flight 10, Hoover. High-speed run to mach 

0.943 at 40 000 ft. 

NACA flight 1 1, Hoover. First NACA supersonic 

flight. First civilian supersonic flight. 

Mach 1.065. Nosewheel failed to extend for 

landing. Minor damage. 

NACA flight. 12, Hoover. Stability and loads investigation. Mach 1.12. 

289 
rz * c 

ON THE FRONTIER 

2. X S - 1 #2 (X-1-2), Serial 46-063, Flights, Continued 

Date Remarks 

30 Mar. 1948 

31 Mar. 

5 Apr. 

9 Apr. 

16 Apr. 

1 Nov. 

15 Nov. 

23 Nov. 

29 Nov. 

30 Nov. 

2 Dec. 

6 May 1949 

13 May 

27 May 

16 June 

23 June 

11 Jul. 

19 Jul. 

27 Jul. 

4 Aug. 

23 Sept. 

30 Nov. 

NACA flight 13, Hoover. Same as flight 12 Mach 

NACA flight 14, Lilly. Same as flight 12. Plane 

NACA flight 15, Lilly. Engine failed to ignite. 

NACA flight 16, Lilly. Save ?s flight 12. Mach 

NACA flight 17, Lilly. Same as flight 12. Plane’s 

0.90. 

attained mach 1.1. 

Propellants jettisoned, completed as glide flight. 

0.89. 

nosewheel collapsed on landing. Moderate damage. 

NACA flight 18, Hoover. Stability and control. 

Mach 0.9. Number 4 cylinder failed to fire. 

NACA flight 19, Hoover. Same as flight 18. Also 

pressure-distribution survey. Mach 0.98. 

NACA flight 20, Robert A. Champine. Pilot familiarization. Check on handling qualities and 

pressure distribution. 

NACA flight 21, Champine. Check on handling 

qualities and pressure distribution. Mach 0.88. 

NACA flight 22, Champine. Same as flight 21. 

NACA flight 23, Champine. Same as flight 21. 

Plane exceeded mach 1 briefly. 

NACA flight 24, Champine. Check on airplane 

instrumentation. Mach 0.88 at 40 000 ft. 

NACA flight 25, Champine. Spanwise pressure 

distribution, stability and control. Mach 0.91. 

NACA flight 26, Champine. Same as flight 25. 

Mach 0.9 1. Stabi!izer found more effective than 

the elevator during pull-ups at mach 0.91. 

NACA flight 27, Champine. Same as flight 25. 

Rolls and pull-ups around mach 0.91. 

NACA flight 28, Champine. Same as flight 25. 

Rolls, pull-ups, check of stabilizer effectiveness. 

NACA flight 29, Champine. Same as flight 25. 

Rolls, pull-ups, check of stabilizer effectiveness. 

Mach 0.91. Number 2 cylinder failed to fire. 

NACA flight 30, Champine. Same as flight 25. 

Rolls, pull-ups, check of stabilizer effectiveness. 

Mach 0.91. Number 2 cylinder failed to fire. 

NACA flight 31, Champine. Same as flight 25. 

Rolls, pull-ups, check of stabilizer effectiveness. 

NACA flight 32, Champine. Same as flight 25. 

Sideslips, rolls, check of stabilizer effectiveness. 

NACA flight 33, John H. Griffith. Pilot familiarization. Mach 0.9. 

NACA flight 34, Griffith. Same as flight 33. Mach 

0.93. 

290 
P 

X-1 FLIGHTS 

2. X S - 1 #2 (X-1-2), Serial 46-063, Flights, Continued 

Date Remarks 

12 May 1950 

17 May 

26 May 

NACA flight 35, Griffith. Same as flight 25. Pull- ups and rolls. 

NACA flight 36, Griffith. Same as flight 25. Push- downs and pull-ups. Mach 1.13 at 42 000 ft. 

NACA flight 37, Griffith. Same as flight 25. Push- downs, pull-ups, rolls. Mach 1.20. Nosewheel 

collapsed on landing. 

NACA flight 38, Griffith. For pressure distribution 

and stability and control data. Check of stabilizer 

effectiveness. Mach 0.98. 

NACA flight 39, Griffith. Same as flight 38. 

NACA flight 40, Griffith. Same as flight 38. Also 

drag investigation. Pull-ups. Mach 0.90. 

NACA flight 41, Griffith. Same as flight 40. 

NACA flight 42, Capt. Charles E. Yeager. Flight 

for RKO filmJet Pilot. Slight engine fire but no 

damage. 

zation. Reached mach 1.07. 

check. 

effectiveness. Aileron rolls at mach 0.90. 

Aileron rolls at mach 1.07. 

Abrupt rudder fixed aileron rolls left and right, 

from mach 0.70 to mach 0.88. 

9 Aug. 

11 Aug. 

21 Sept. 

4 Oct. 

6 Apr. 1951 

20 Apr. 

27 Apr. 

15 May 

12 Jul. 

20 Jul. 

NACA flight 43, A. Scott Crossfield. Pilot familiariNACA flight 44, Crossfield. Plane and instrument 

NACA flight 45, Crossfield. Wing loads and aileron 

NACA flight 46, Crossfield. Same as flight 45. 

NACA flight 47, Crossfield. Same as flight 45. 

31 Jul. 

3 Aug. 

8 Aug. 

10 Aug. 

27 Aug. 

NACA flight 48, Crossfield. Same as flight 45. 

NACA flight 49, Crossfield. Same as flight 45. 

NACA flight 50, Crossfield. Same as flight 45. 

Elevator and stabilizer pull-ups. 

NACA flight 51, Crossfield. Same as flight 45. 

Elevator and stabilizer pull-ups, clean stalls. 

NACA flight 52, Joseph A. Walker. Pilot familiari- zation. Reached mach 1.16 at 44 000 ft during 

four-cylinder run. 

distribution survey. Number 1 cylinder failed to 

fire. Stabilizer pull-ups at mach 1.07. 

NACA flight 54, Walker. Vortex-generator investigation. Engine cut out after two ignition 

attempts; propellants jettisoned and flight completed as glide flight. Flap actuator failed, so 

landing made flaps-up. Plane subsequently 

grounded because of possibility of fatigue failure 

of nitrogen spheres. Later rebuilt as the mach 

2+ X-1E. 

5 Sept. NACA flight 53, Crossfield. Fuselage pressure 

23 Oct. 

29 1 
ON THE FRONTIER 

3. X - 1 #3 (X-1-31, Serial 46-064, Flights 

Date Remarks 

20 Jul. 1951 

9 Nov. 

Bell flight 1, Joseph Cannon, pilot. Glide flight for 

familiarization. Nosewheel collapse on landing. 

Bell flight 2, Cannon. Captive flight with B-50 for 

propellant jettison test. X- 1-3 destroyed in 

postflight explosion and fire on gound. B-50 

launch plane also lost and Cannon injured. 

4. X-lA, Serial 48-1384, Flights 

Date Remarks 

Bell Contractor Flights 

14 Feb. 1953 

20 Feb. 

Bell flight 1, Jean Ziegler, pilot. Familiarization. 

Fuel jettison test. Glide flight only. 

Bell flight 2, Ziegler. Planned as powered flight, 

but completed as glide flight following propellant-system difficulties. 

Bell flight 3, Ziegler. First powered flight. False 

fire warning. 

Bell flight 4, Ziegler. Plane demonstrated successful 

4-cylinder engine operation. 

Bell flight 5, Ziegler. Pilot noted low-frequency 

elevator buzz at mach 0.93, did not proceed 

above this speed, pending buzz investigation. 

Bell flight 6, Ziegler. Buzz again noted at mach 

0.93. Turbopump overspeeding caused pilot to 

terminate power and jettison remaining fuel. 

21 Feb. 

26 Mar. 

10 Apr. 

25 Apr. 

Air Force Flights (After USAF took over remaining Bell program on X- 1A and initiated 

its own flight program) 

21 Nov. 1953 

2 Dec. 

8 Dec. 

12 Dec. 

Flight 7, Maj. Charles E. Yeager. First Air Force 

flight. Reached mach 1.15. Familiarization purposes. 

Flight 8, Yeager. Mach 1.5. 

Flight 9, Yeager. First high-mach flight attempt by 

X-IA. Mach 1.9 attained at 60 000 ft during 

slight climb. 

Flight 10, Yeager. Plane attained mach 2.44, but 

met violent instability above mach 2.3. Tumbled 

50 000 ft, wound up in subsonic inverted spin. 

Yeager recovered to upright spin, then into normal flight at 25 000 ft. 

Fourteen Air Force flight attempts for high altitudes were made in the spring and 

summer of 1954. Of these, only 4 flights were successful. The rest were aborted for 

292 
X-1 FLIGHTS 

4. X-lA, Serial 48-1384, Flights, Continued 

Date Remarks 

various malfunctions, including ruptured canopy seal, failure of gear doors to close fully, 

turbine overspeed, faulty ignition operation. Of the 4 successful flights, one was Maj. 

Arthur Murray’s checkout flight. The rest were successful high-altitude tries by Murray. 

The successful altitude flights were: 

28 May 1954 

4 June 

26 Aug. 

NACA Flights 

20 July 1955 

8 Aug. 

Flight 16, Murray. X- 1A attained 87 094 ft, unofficial world altitude record for manned aircraft. 

Flight 17, Murray. X-1A reached 89 750 ft. Encountered same instability Yeager had, but at 

mach 1.97. Murray recovered after tumbling 

20 000 ft down to 66 000 ft. 

Flight 24, Murray. Murray attained 90 440 ft. Air 

Force then turned X- 1A over to NACA. 

NACA flight 1, Joseph A. Walker. Familiarization. Walker attained mach 1.45 at 45 000 ft. 

Noted severe aileron buzz at mach 0.90 to 0.92. 

Planned as NACA flight 2. Shortly before launch 

from B-29, X- IA suffered low-order explosion, later traced to detonation of Ulmer leather 

gaskets. Walker exited into B-29 bomb bay. 

Extent of damage prohibited landing crippled 

X- IA, and NACA B-29 launch crew jettisoned 

it into desert. It exploded and burned on impact. 

5. X-lB, Serial 48-1385, Flights 

Date Remarks 

Air Force Flights 

24 Sept. 1954 

6 Oct. 

8 Oct. 

13 Oct. 

19 Oct. 

26 Oct. 

4 Nov. 

X- 1B Air Force flight 1, Lt. Col. Jack Ridley, 

pilot. Glide flight, because of turbopump overspeeding. 

aborted power flight because of evidence of high 

lox-tank pressure. 

X- 1B Air Force flight 3, Maj. Arthur “Kit” Murray. 

First powered flight. 

X- 1B Air Force flight 4, Maj. Robert Stephens. 

X- 1B Air Force flight 5, Maj. Stuart R. Childs. 

X-IB Air Force flight 6, Col. Horace B. Hanes. 

X- 1B Air Force flight 7, Capt. Richard B. Harer. 

X- 1B Air Force flight 2, Ridley. Glide flight, 

293 
ON THE FRONTIER 

5. X- IB, Serial 48-1385, Flights, Continued ~ 

Date Remarks 

26 Nov. 1954 

30 Nov. 

2 Dec. 

X-1B Air Force flight 8, Brig. Gen. J. Stanley 

Holtoner (commander, Air Force Flight Test 

Center) . X- 1B Air Force flight 9, Lt. Col. Frank K. Everest. 

X- 1B Air Force flight 10, Everest. Mach 2.3 

(approx. 1520 mph) at 65 000 ft. 

NACA Flights 

John B. McKay pilot on flights 1-13 

Neil A. Armstrong pilot on flights 14- 17 

14 Aug. 1956 

29 Aug. 

7 Sept. 

18 Sept. 

28 Sept. 

3 Jan. 1957 

22 May 

7 June 

24 June 

11 Jul. 

19 Jul. 

29 Jul. 

8 Aug. 

15 Aug. 

27 Nov. 

X-1B NACA flight 1. Pilot check; nose landing 

X- 1B NACA flight 2. Cabin-pressure regulator 

gear failed on landing, minor damage. 

malfunction causes inner canopy to crack; only 

low-speed, low-altitude maneuvers made. 

X- 1B NACA flight 3. Speed run to 56 000 ft 

and mach 1.8. Limited heating data gathered. 

X- 1B NACA flight 4. Glide flight, due to erratic 

engine start. 

X- 1B NACA flight 5. Three-chamber engine run 

to 60 000 ft to obtain heating data. 

X-1B NACA flight 6. Mach 1.94 aerodynamic 

heating investigation (end of heating program). 

X- 1B NACA flight 7. Control pulses at mach 1.45 

at 60 000 ft. Flight for instrumentation check. 

X- 1B NACA flight 8. Supersonic maneuvers to 

mach 1.5 at 60 000 ft. to determine the dynamic 

and static stability and control characteristics. 

X- 1B NACA flight 9. Supersonic maneuvers to 

mach 1.5 at 60 000 ft to determine the dynamic 

and static stability and control characteristics. 

indication of open landing-gear door. Propellants 

jettisoned, completed as a glide flight. 

X- 1B NACA flight 11. Mach 1.65 at 60 000 ft. 

Control pulses, sideslips, and 2 g wind-up turn. 

X- 1B NACA flight 12. Enlarged wing tips installed 

to simulate wing tips to be used with reaction 

controls. Mach 1.55 at 60 000 ft. 

X- 1B NACA flight 13. Stability and control investigation. Mach 1.5 at 60 000 ft, accelerated 

maneuvers, control pulses, and pull-ups. 

X- 1B NACA flight 14. Pilot check for Armstrong. 

Nose landing gear failed on landing, minor 

damage. 

X- 1B NACA flight 15. First reaction-control 

flight. 

X- 1B NACA flight 10. Aborted after launch, 

294 
X-1 FLIGHTS 

5. X - 1 B, Serial 48 - 1385, Flights, Continued 

Date Remarks 

16 Jan. 1958 

23 Jan. 

X- 1B NACA flight 16. Low-altitude, low-mach 

reaction-control investigation. 

X- 1B NACA flight 17. Reaction-control investigation. Mach 1.5 at 55 000 ft. Last NACA flight. 

6. X-ID, Serial 48-1386, Flights 

Date Remarks 

Bell Contractor Flights 

24 Jul. 1951 

Air Force Flights 

22 Aug. 1951 

Bell flight 1, Jean Ziegler, pilot. Glide flight for 

familiarization. Nose landing gear broken on 

landing. Following repairs, plane turned over to 

the Air Force. 

AF flight 1, Lt. Col. Frank K. Everest. Launch 

aborted, but X- 1D suffered low-order explosion 

during pressurization for fuel jettison. Plane 

jettisoned from B-50. X- ID exploded on 

impact with desert. Everest managed to get into 

B-50 bomb bay before drop. B-50 not damaged, 

no personal injuries. 

7. X - 1 E, Serial 46 -063, Flights 

Date Remarks 

Joseph Walker pilot for flights 1-21 

John McKay pilot for flights 22-26 

3 Dec. 1955 

12 Dec. 

15 Dec. 

3 Apr. 1956 

30 Apr. 

Captive flight. 

X- 1E NACA flight 1. Glide flight for pilot checkout and low speed evaluation. 

X- 1E NACA flight 2. First powered flight. Engine 

ran at excessive pressure, 4 overspeeds of turbopump and 2 automatic shutdowns. Power terminated by pilot. 

Damping characteristics good; number 1 cylinder 

failed to fire. 

no engine operation. 

X-1E NACA flight 3. Mach 0.85 at 30 000 ft. 

X- 1E NACA flight 4. Turbopump did not start; 

295 
ON THE FRONTIER 

Date 

11 May 1956 

7 June 

18 June 

26 Jul. 

31 Aug. 

14 Sept. 

20 Sept. 

3 Oct. 

20 Nov. 

25 Apr. 1957 

15 May 

19 Sept. 

8 Oct. 

14 May 1958 

10 June 

10 Sept. 

17 Sept. 

19 Sept. 

30 Sept. 

7. X-lE, Serial 46-063, Flights, Continued 

Remarks 

X- 1E NACA flight 5. Wind-up turns to CL, 

from mach 0.69 to 0.84; also control pulses. 

X- 1E NACA flight 6. Mach 1.55 at 45 000 ft 

(approx. 1020 mph). Longitudinal and lateral 

trim changes in transonic region found annoying 

to pilot. 

X-1E NACA flight 7. Mach 1.74 at 60 000 ft 

(approx. 1150 mph). Damaged on landing. 

X- 1E NACA flight 8. Subsonic because cylinders 

3 and 4 would not fire. 

X- 1E NACA flight 9. Mach 2.0 at 60 000 ft 

(approx 1340 mph). Sideslips, pulses, rolls. 

X-1E NACA flight 10. Mach 2.1 at 62 000 ft 

(approx 1385 mph). Stabilizer, rudder, and 

aileron pulses. 

X- 1E NACA flight 11. Brief engine power only; 

flight aborted, unspecified engine malfunction. 

X- 1E NACA flight 12. Only 60-sec rocket operation; intermittent pump operation. Flight aborted, 

turbopump and engine replaced. 

X- 1E NACA flight 13. No engine operation, 

ignition failure and lack of manifold pressure. 

X-1E NACA flight 14. Mach 1.71 at 67 000 ft. 

(approx 1130 mph). Aileron and rudder pulses. 

X- 1E NACA flight 15. Mach 2.0 at 73 000 ft. 

(approx. 1325 mph). Aileron pulses and rolls, 

sideslips, and wind-up turns. Plane severely 

damaged upon landing. 

X- 1E NACA flight 16. Planned mach number not 

attained, loss of power during pushover from 

climb. 

X- 1E NACA flight 17. Mach 2.24 (approx. 1480 

X-1E NACA flight 18. First flight with ventral 

fins; longitudinal and lateral stability and control 

maneuvers. Engine airstart made at 70 000 ft. 

X- 1E NACA flight 19. Flight aborted after only 1 

cylinder of engine fired. Plane damaged on 

landing. 

X- 1E NACA flight 20. Stability and control investigation with ventral fins. 

X-1E NACA flight 21. Stability and control with 

ventral fins and a new stabilizer bell crank 

permitting greater stabilizer travel. 

McKay. 

McKay, also check of low-speed stability and 

control. 

mph). 

X- 1E NACA flight 22. Checkout flight for John 

X- 1E NACA flight 23. Checkout flight for 

296 
X-1 FLIGHTS 

7. X - 1 E, Serial 46 - 063, Flights, Continued 

Date Remarks 

16Oct. 1958 X- 1E NASA flight 24. First flight with elevated 

chamber pressure; cut short because overcast 

obscured pilot’s view of lakebed. 

X- 1E NASA flight 25. Elevatedchamber pressure; 

good stability and control data gathered. 

X- 1E NASA flight 26. Elevated chamber pressure; 

low-altitude and low-mach investigation of UDeta fuel. Last NASA flight. 

28 Oct. 

6 Nov. 

SOURCE Richard P. Hallion, Supersonic Flight: Breaking the Sound Ba& and Beyond-The Story of 

the Bell X - 1 and Dough D-558 (New York: Macmillan Company in association with 

Srnithsonian Institution, 1972), pp. 209-20. 

297 

a 

Appendix G 

Douglas D- 558 Program Flight Chronology, 

194’7- 1956 

This chronology covers flights by the three Douglas D-558-1 Skystreaks and the 

three Douglas D-558-2 Skyrockets. 

The D-558-1 Skystreak was a turbojet powered aircraft that took off from the 

ground under its own power. It featured a straight wing and tail section. 

The D-558-2 Skyrocket was powered both by a turbojet engine and a liquid-fuel 

rocket engine, and also took off from the ground. In 1950, however, the D-558-2 #2 

(BuAer no. 37974) was modified for all-rocket air-launch from a B-29 mothership, 

enhancing greatly its safety and performance potential. Another D-558-2 #2 (BuAer 

no. 37975) was also modified for air-launch, but retained both its turbojet and rocket 

engine. The D-558-2 #1 (BuAer no. 37973) was likewise later modified for all-rocket 

operation, but completed only one flight before termination of the entire Skyrocket 

program. 

1. D-558-1 #I, BuAer No. 37970 Flight Highlights 

This aircraft completed 101 flights during its Douglas contractor program. Douglas 

delivered it to NACA on 21 April 1949, but NACA never flew it, relegating it 

to spares support for the D-558- 1 #3. 

Date Remarks 

14 Apr. 1947 Douglas flight 1, Eugene F. May, pilot. For 

familiarization. Partial power loss forced 

immediate landing after takeoff. 

Douglas flight 14, May. Beginning of performance 

investigations at high mach numbers. Mach 

0.8 1. 

Douglas flight 25, Comdr. Turner F. Caldwell, Jr., 

USN. Set new world airspeed record of 

640.663 mph. 

Douglas flight (?), May. Plane exceeded mach 1 

during 35-degree dive, only time a Skystreak 

attained mach 1. 

17 Jul. 

20 Aug. 

29Sept. 1948 

299 
ON THE FRONTIER 

2. D-558-1 #2, BuAer No. 37971, Flights 

Date Remarks 

Howard C. Lilly, pilot 

(27 previous flights made by Douglas, Navy, and Marine pilots) 

25 Nov. 1947 

26 Nov. 

16 Feb. 1948 

31 Mar. 

1 Apr. 

7 Apr. 

8 Apr. 

NACA flight 1. Pilot familiarization; instrumentaNACA flight 2. Landing gear would not lock up. 

NACA flight 3. Attempted airspeed calibration; 

NACA flight 4. Landing gear door would not lock. 

NACA flight 5. Landing gear door would not lock. 

NACA flight 6. Landing gear door would not lock. 

NACA flight 7. Landing gear door would not lock. 

NACA flight 8. Attempted airspeed calibration; 

NACA flight 9. Airspeed calibration, 30 000 ft. 

NACA flight 10. Airspeed calibration, 30 000 ft. 

NACA flight 1 1. Airspeed calibration, tower fly-by. 

NACA flight 12. Airspeed calibration, 30 000 ft. 

NACA flight 13. Smoke in cockpit after takeoff 

necessitated landing. Smoke due to burning 

400-cycle inverter in nose compartment; inverter replaced. 

NACA flight 14. Sideslips at 10 000 ft from mach 

0.50 through 0.85, for static directional stability. 

NACA flight 15. Sideslips at 30 000 ft from mach 

0.50 through 0.85, for static directional stability. 

NACA flight 16. Right landing gear would not 

retract. 

NACA flight 17. Two speed runs; mach 0.70 at 

41 000 ft, mach 0.88 at 36 000 ft. Left and 

right rudder kicks at 10 000 ft. 

tion malfunction. 

instrumentation malfunction. 

radar beacon failure. 

9 Apr. 

12 Apr. 

14 Apr. 

20 Apr. 

23 Apr. 

28 Apr. 

29 Apr. 

3 May NACA flight 18. Landing gear would not retract. 

NACA flight 19. Crash after takeoff due to 

compressor disintegration; Lilly killed. 

-3. 0-558-1 #3, BuAer No. 37972, Flights 

Date Remarks 

(Four flights made in early 1948 by Douglas pilots and Howard Lilly) 

22 Apr. 1949 

28 Apr. 

12 Aug. 

300 

NACA flight 1, Robert A. Champine, pilot. For 

NACA flight 2, Champine. Pilot check; dive to 

NACA flight 3, Champine. Handling qualities 

pilot familiarization. 

mach 0.87. 

(rudder kicks, aileron rolls, sideslips); dive to 

mach 0.9. 
D-558 FLIGHTS 

3. D-558-1 #3, BuAer No. 37972, Flights, Continued 

Date Remarks 

18 Aug. 1949 

19 Aug. 

23 Aug. 

24 Aug. 

31 Aug. 

28 Sept. 

30 Oct. 

21 Nov. 

23 Nov. 

26 Jan. 1950 

15 Feb. 

5 Apr. 

11 Apr. 

3 May 

NACA flight 4, Champine. Handling qualities; 

dive to mach 0.875. 

NACA flight 5, John H. Griffith, pilot check, 

handling qualities; trim run to mach 0.84. 

NACA flight 6, Griffith. Airspeed calibration 

using tower passes. 

NACA flight 7, Champine. Handling qualities; 

dive to mach 0.87. 

NACA flight 8, Champine. Aileron effectiveness 

investigation; no records taken. 

NACA flight 9, Griffith. Aileron effectiveness 

investigations; 16 rolls made, 4 above mach 0.87. 

NACA flight 10, Griffith. Beginning of pressure- distribution survey. 

NACA flight 1 1, Griffith. Pressure-distribution 

investigation. 

NACA flight 12, Champine. Pressure-distribution 

investigation. 

NACA flight 13, Champine. Check of airspeed 

system. 

NACA flight 14, Champine. Aborted, engine malfunction. 

NACA flight 15, Griffith. Pressure-distribution 

investigation. Mach 0.95 attained. 

NACA flight 16, Griffith. Pressure-distribution 

investigation. Mach 0.98 attained. 

NACA flight 17, Griffith. Vortex generator- investigation as part of pressure-distribution 

investigation. Mach 0.97 attained. 

NACA flight 17A, Griffith. Vortex generatorinvestigation as part of pressure-distribution 

investigations. 

distributor investigation. Mach 0.87 attained. 

distributor investigation. Mach 0.98 attained. 

distributor investigation. 

distributor investigation. 

distributor investigation. Mach 0.98- 1 .O. Conclusion of pressure-distribution investigation. 

NACA flight 23, Griffith. Instrument and operational check flight in preparation for the buffeting 

tail loads and longitudinal stability investigation. 

NACA flight 24, A. Scott Crossfield, pilot check. 

Beginning of buffeting, tail loads, and longitudinal stability program. 

5 May 

11 May 

18 May 

31 May 

8 June 

13 June 

NACA flight 18, Griffith. Vortex generatorNACA flight 19, Griffith. Vortex generatorNACA flight 20, Griffith. Vortex generatorNACA flight 2 1, Griffith. Vortex generatorNACA flight 22, Griffith. Vortex generator26 Oct. 

29 Nov. 

30 1 
ON THE FRONTIER 

3. D-558- 

Date 

12 Dec. 1950 

18 Dec. 

20 Dec. 

26 Dec. 

5 Jan. 1951 

23 Jan. 

25 Jan. 

8 Feb. 

13 Feb. 

20 Feb. 

2 May 

1 June 

13 June 

21 June 

28 June 

29 June 

5 Jul. 

17 Jul. 

20 Jul. 

26 Jul. 

30 Jul. 

2 Aug. 

7 Aug. 

302 

1 #3, BuAer No. 37972, Flights, Continued 

Remarks 

NACA flight 25, Crossfield. Buffeting, tail loads, 

longitudinal stability investigation. 

NACA flight 26, Crossfield. Buffeting, tail loads, 

dynamic longitudinal stability added to longitudinal stability program. 

NACA flight 27, Crossfield. Longitudinal stability 

program. 

NACA flight 28, Crossfield. Longitudinal stability 

program. 

NACA flight 29, Crossfield. Longitudinal stability 

program. 

NACA flight 30, Crossfield. Longitudinal stability 

program. Aborted, fuel leak. 

NACA flight 3 1, Crossfield. Longitudinal stability 

program. 

NACA flight 32, Crossfield. Airspeed calibration, 

5 tower passes. 

NACA flight 33, Walter P. Jones. Pilot check; some 

buffeting, tail loads, and longitudinal stability 

data taken. 

NACA flight 34, Jones. Aborted after Jones suffered anoxia, faulty 02 regulator. 

NACA flight 35, Jones. Buffeting, tail loads, longitudinal stability investigation. 

NACA flight 36, Crossfield. Buffeting, tail loads, 

longitudinal stability investigation. Mach 0.84. 

NACA flight 37, Crossfield. Buffeting, tail loads, 

longitudinal stability investigation. Mach 0.86. 

NACA flight 38, Crossfield. Buffeting, tail ioads, 

longitudinal stability investigation. Mach 0.835. 

NACA flight 39, Jones. Buffeting, tail loads, longitudinal stability investigation. Mach 0.85. 

NACA flight 40, Joseph A. Walker, Pilot check. 

Mach 0.82. 

NACA flight 41, Walker. Buffeting, tail loads, 

longitudinal stability. 

NACA flight 42, Walker. Buffeting, tail loads, 

longitudinal stability. (Cut short, made without 

tip tanks.) 

longitudinal stability. 

longitudinal stability. Mach 0.83; cut short, bad 

cloud formation. 

longitudinal stability. Mach 0.85. 

longitudinal stability. Mach 0.84. 

tudinal stability. Mach 0.86. 

NACA flight 43, Walker. Buffeting, tail loads, 

NACA flight 44, Walker. Buffeting, tail loads, 

NACA flight 45, Walker. Buffeting, tail loads, 

NACA flight 46, Walker. Buffeting, tail loads, 

NACA flight 47, Jones. Buffeting, tail loads, longi- 
D-558 FLIGHTS 

3. 0-558-1 #3, BuAer No. 37972, Flights, Continued 

Date Remarks 

10 Aug. 1951 

20 Aug. 

22 Aug. 

30 Aug. 

6 Sept. 

14 Sept. 

18 Oct. 

19 Oct. 

9 Nov. 

27 June 1952 

2 Jul. 

17 Jul. 

22 Jul. 

31 Jul. 

6 Aug. 

12 Aug. 

29 Jan. 1953 

6 Feb. 

11 Feb. 

17 Feb. 

20 Feb. 

27 Mar. 

NACA flight 48, Walker. Flight cut short due to a 

fuel leak. 

NACA flight 49, Walker. Buffeting, tail loads, 

longitudinal stability. Mach 0.875. 

NACA flight 50, Walker. Flight cut short, hydraulic 

line broke. 

NACA flight 51, Walker. Instrument malfunction. 

Mach 0.86. 

NACA flight 52, Walker. Buffeting, tail loads, 

longitudinal stability. Mach 0.86. 

NACA flight 53, Walker. Buffeting, tail loads, 

longitudinal stability. Mach 0.84. 

NACA flight 54, Walker. Buffeting, tail loads, 

longitudinal stability. Beginning of lateral 

stability investigation. Mach 0.86. 

NACA flight 55, Stanley P. Butchart. Pilot check. 

NACA flight 56, Butchart. Pilot check. 

NACA flight 57, Crossfield. Beginning of lateral 

stability and control (aileron effectiveness) 

investigation. 

NACA flight 58, Crossfield. Lateral stability and 

control. Mach 0.85. 

NACA flight 59, Butchart. Lateral stability and 

control. Also beginning of a simultaneous 

dynamic longitudinal stability investigation. 

NACA flight 60, Butchart. Lateral stability and 

control. Simultaneous dynamic longitudinal 

stability investigation. 

NACA flight 61, Butchart. Lateral stability and 

control. Simultaneous dynamic longitudinal 

stability investigation. 

NACA flight 62, Butchart. Lateral stability and 

control. Simultaneous dynamic longitudinal 

stability investigation. 

NACA flight 63, Butchart. Lateral stability and 

control. Completion of lateral stability (aileron 

effectiveness) program. 

investigation. 

investigation. 

investigation. 

investigation. 

investigation. Conclusion of dynamic stability 

flights. 

NACA flight 64, Butchart. Dynamic stability 

NACA flight 65, Butchart. Dynamic stability 

NACA flight 66, Butchart. Dynamic stability 

NACA flight 67, Butchart. Dynamic stability 

NACA flight 68, Butchart. Dynamic stability 

NACA flight 69, John B. McKay. Pilot check. 

303 
a 

ON THE FRONTIER 

3. 0-558-1 #?, BuAer No. 37972, Flights, Continued 

Date Remarks 

1 Apr. 1953 

2 Apr. 

7 May 

12 May 

13 May 

2 June 

3 June 

10 June 

NACA flight 70, McKay. Flight for dynamic stability 

fill-in data. 

NACA flight 71, McKay. Flight for dynamic 

stability fill-in data. 

NACA flight 72, McKay. Beginning investigation 

of tip tanks’ effect on Skystreak‘s buffet characteristics. Aborted, leak in tip tank. 

NACA flight 73, McKay. Tip tank-buffet investigation. No records taken. 

NACA flight 74, McKay. Tip tank-buffet investigation. 

NACA flight 76, McKay. Tip tank-buffet investigation. Also low-speed stability-and-control-incoordinated-turns investigation. 

NACA flight 77, McKay. Tip tank-buffet investigation. Also low-speed stability-and-control-incoordinated-turns investigation. 

vestigation. Also low-speed stability-and-controlin-coordinated-turns investigation. Last research 

flight flown by Skystreak. 

NACA flight 78, Crossfield. Tip tank-buffet in4. 0-558-2 #I, BuAer No. 37973, Flights 

This aircraft completed 122 flights during its Douglas contractor program. The first 

flight was on 4 Feb. 1948, by John F. Martin. After initial flight testing, and addition of 

its rocket engine, Douglas began performance investigation in the aircraft on 25 Oct. 1949. 

Douglas delivered the craft to NACA on 31 Aug. 1951. NACA sent it to Douglas in 1954 

for all-rocket air-launch modification, for external stores tests at supersonic speeds. The 

aircraft returned to Edwards on 15 Nov. 1955. NACA research pilot John McKay completed a familiarization flight on 17 Sept. 1956, but NACA subsequently canceled the 

remaining planned program. 

5. D-558-2 #2, BuAer No. 37974, Flights 

Date Remarks 

NACA Jet-Powered Flights 

Robert A. Champine and John H. Griffith, pilots 

24 May 1949 

1 June 

NACA flight 1, Champine. Pilot and instrument 

check, general handling qualities. Mach 0.74. 

NACA flight 2, Champine. Longitudinal and lateral 

stability and control, wing bending and twist. 

Mach 0.85. 

304 
e 

D-558 FLIGHTS 

5. 0-558-2 #2, BuAer No. 37974, Flights, Continued 

Date Remarks 

13 June 1949 

21 Jul. 

27 Jul. 

3 Aug. 

8 Aug. 

NACA flight 3, Champine. Longitudinal and lateral 

stability and control, wing and tail loads. 

NACA flight 4, Champine. Unsuccessful airspeed 

calibration, airspeed-altitude recorder failure. 

NACA flight 5, Champine. Successful airspeed 

calibration, using tower passes. 

NACA flight 6, Champine. Lateral control investi- gation. 

NACA flight 7, Champine. Longitudinal stability 

and control; inadvertent pitch-up to 6 g during 

a 4 g turn at mach 0.60. 

NACA flight 8, Champine. Longitudinal stability 

and lateral control investigation during maneuvering flight. Mach 0.855. 

NACA flight 9, Champine. Aborted after takeoff, 

fluctuations in engine RPM and oil pressure. 

NACA flight 10, Griffith. Longitudinal and lateral 

stability and control. Only partial completion of 

mission, one JATO bottle failed to drop. 

NACA flight 11, Griffith. Longitudinal and lateral 

stability and control. High engine temperatures. 

NACA flight 12, Champine. Longitudinal and 

lateral stability and control, stall characteristics. 

NACA flight 13, Griffith. Same as flight 12. 

NACA flight 14, Griffith. Same as flight 12. In24 Aug. 

30 Aug. 

12 Sept. 

13 Sept. 

10 Oct. 

14 Oct. 

1 Nov. 

advertent pitch-up and snap-roll, later pitch-up 

followed by stall, spin. 

NACA flight 15, Champine. Lateral stability and 

control, and directional stability investigation 

(aileron rolls). Mach 0.855. 

21 Nov. 

22 Nov. 

23 Nov. 

7 Dec. 

30 Dec. 

6 Jan. 1950 

NACA flight 16, Griffith. Same as flight 15. 

NACA flight 17, Griffith. Same as flight 15. 

NACA flight 18, Champine. Same as flight 15. 

NACA flight 19, Griffith. Stall investigation with 

NACA flight 20, Griffith. Same as flight 19. 

NACA flight 21, Griffith. Same as flight 19. 

tufts. 

Douglas Air-Launch Rocket Flights 

William B. Bridgeman, pilot 

8Nov. 1950 

26 Jan. 1951 

5 Apr. 

0-558-2 #2 (37974) arrived at Edwards from 

Douglas via B-29 (P2B- IS) launch aircraft. 

Douglas flight 1. Air launch at 32 000 ft, climb to 

41 000 ft, level run to mach 1.28. Dutch-roll 

oscillation, loss of elevator effectiveness noted. 

Douglas flight 2. Drop at 34 000 ft, maximum mach 

of 1.36 at 46 500 ft. Severe lateral oscillation 

305 
ON THE FRONTIER 

5. D-558-2 #2, BuAer No. 37974, Flights, Continued 

Date Remarks 

18 May 1951 

11 June 

23 June 

7 Aug. 

15 Aug. 

31 Aug. 

NACA Air-Launch Rocket Flights 

31 Aug. 1951 

28 Sept. 

12 Oct. 

13 Nov. 

16 Nov. 

13 June 1952 

18 june 

26 June 

10 Jul. 

15 Jul. 

23 Jul. 

13 Aug. 

forced Bridgeman to shut off engine prematurely. 

Rudder lock subsequently installed to control 

rapid rudder oscillation. 

Douglas flight 3. Launch at 34 000 ft, maximum 

mach of 1.7 at 62 000 ft. Loss of rocket power. 

Rudder locked at all speeds above mach 1. 

Douglas flight 4. Mach 1.79 at 64 000 ft. Low lateral 

stability, also a lightly damped longitudinal oscillation noted after burnout. 

Douglas flight 5. Mach 1.85 at 63 000 ft. Violent 

lateral oscillation necessitated engine shutdown. 

Wing rolling + and -80deg. (1.5 radians per sec). 

Douglas flight 6. Mach 1.88 at 66 000 ft. Dynamic 

lateral instability not as severe on this flight, for 

Bridgeman did not push over to as low an angle 

of attack as on previous flights. 

Douglas flight 7. Altitude flight to 79 494 ft. 

Unofficial world’s altitude record. 

D-558-2 #2 turned over to NACA. 

Plane delivered to NACA HSFRS. 

NACA flight 1, A. Scott Crossfield. Pilot check, 

mach 1.2, rough engine operation. 

NACA flight 2, Crossfield. Stick impulses and 

rudder kicks, mach 1.28. 

NACA flight 3, Crossfield. Mach 1.1 1. Longitudinal 

and lateral stability and control, loads data, and 

aileron effectiveness. 

NACA flight 4, Crossfield. Same as flight 3. 

Maximum mach 1.65 at 60 000 ft. 

NACA flight 5, Crossfield. Lateral stability and 

control, vertical tail loads. Mach 1.36. 

NACA flight 6, Crossfield. Stability and control, 

loads in low supersonic flight. Mach 1.05. 

NACA flight 7, Crossfield. Same as flight 6. Mach 

1.35. 

NACA flight 8, Crossfield. Longitudinal stability 

and tail loads. Mach 1.68 at 55 000 ft. 

NACA flight 9, Crossfield. Longitudinal stability 

and tail loads. Mach 1.05, engine malfunction 

caused low mach. 

NACA flight 10, Crossfield. High lift investigation 

at maximum mach. Mach 1.5 1. 

NACA flight 11, Crossfield. Aborted after launch, 

lox prime valve remained open. 

306 
D-558 FLIGHTS 

5. D-558-2 #2, BuAer No. 37974, Flights, Continued 

Date Remarks 

1OOct. 1952 NACA flight 12, Crossfield. Longitudinal stability 

at supersonic speeds. Mach 1.65. Pitch-up noted 

in turns. 

mach 1.10. 

23 Oct. 

26 Mar. 1953 

2 Apr. 

NACA flight 13, Crossfield. Same as flight 12, 

NACA flight 14, Crossfield. Same as flight 12. 

NACA flight 15, Crossfield. Lateral stability and 

handling qualities investigation. Beginning of 

series of flights to evaluate lateral stability at 

various angles of attack above mach 1. 

NACA flight 16, Crossfield. Lateral stability 

investigation. 

NACA flight 17, Crossfield. Lateral stability 

investigation. 

NACA flight 18, Crossfield. Lateral stability 

investigation. 

NACA flight 19, Crossfield. Aborted after drop; 

engine running rough, so was shut down. 

NACA flight 20, Crossfield. Lateral stability 

investigation. Mach 1.878. 

NACA flight 21, Lt. Col. Marion Carl, USMC. 

Unsuccessful altitude attempt. 

NACA flight 22, Carl. Unsuccessful altitude attempt. 

NACA flight 23, Carl. Successful altitude flight to 

83 235 ft. 

NACA flight 24, Carl. Maximum mach flight 

attempt. Mach 1.5. Violent lateral motions. 

NACA flight 25, Carl. Maximum mach flight 

attempt, to mach 1.728 at 46 000 ft. 

NACA flight 26, Crossfield. 1st flight with nozzle 

extensions. Mach 1.85 at 74 000 ft. 

NACA flight 27, Crossfield. Lateral stability 

investigation. Mach 1.8 at 55 000 ft. Severe 

lateral instability. 

NACA flight 28, Crossfield. Lateral stability 

investigation. 

NACA flight 29, Crossfield. To obtain data on 

effect of rocket-nozzle extensions on rudderhinge-moment parameter. 

investigation. Attained mach 1.96. 

investigation. No. 2 chamber failed to ignite, 

engine shut down prematurely. Subsonic flight 

only. 

NACA flight 32, Crossfield. Aerodynamic loads and 

longitudinal control research flight. 

3 Apr. 

21 Apr. 

9 June 

18 June 

5 Aug. 

14 Aug. 

18 Aug. 

21 Aug. 

31 Aug. 

2 Sept. 

17 Sept. 

25 Sept. 

7 Oct. 

9 Oct. 

14 Oct. 

29 Oct. 

NACA flight 30, Crossfield. Lateral stability 

NACA flight 3 1, Crossfield. Lateral stability 

4 Nov. 

307 
b 

ON THE FRONTIER 

5. D-558-2 #2, BuAer No. 37974, Flights, Continued 

Date Remarks 

6Nov. 1953 

20 Nov. 

NACA flight 33, Crossfield. Lateral and longitudinal 

NACA flight 34, Crossfield. First mach 2.0 flight. 

stability and control, loads research. 

Plane attained mach 2.005 in slight dive at 

62 000 ft. 

11 Dec. 

23 Dec. 

9 Jul. 1954 

14 Ju1. 

NACA flight 35, Crossfield. Aborted, fire warning 

light. Engine shut down, frozen valve. 

NACA flight 36, Crossfield. For rudder-hingemoment data with rocket-nozzle extensions. 

NACA flight 37, Crossfield. Dynamic lateral 

stability investigation. 

NACA flight 38, Crossfield. Same as flight 37, also 

structural loads investigation, and wing pressuredistribution survey. 

21 Ju1. 

26 Jul. 

NACA flight 39, Crossfield. Same as flight 38. 

NACA flight 40, Crossfield. Static and dynamic 

stability and control, loads, and pressure 

distribution. Mach 1.7 at 60 000 ft. 

NACA flight 41, Crossfield. Same as flight 40. 

NACA flight 42, Crossfield. Same as flight 40. 

6 Aug. 

13 Aug. 

Pitch-up encountered in turn at mach 1.08, plane 

pitched to 5.8 g with heavy buffeting. 

20 Aug. 

17 Sept. 

22 Sept. 

4 Oct. 

27 Oct. 

NACA flight 43, Crossfield. Same as flight 40. 

NACA flight 44, Crossfield. Same as flight 40. 

NACA flight 45, Crossfield. Same as flight 40. 

NACA flight 46, Crossfield. Dynamic lateral 

stability data to mach 1.5. 

NACA flight 47, Crossfield. Same as flight 46. 

Engine shut down, pump overspeed during 

climb. 

distribution and buffeting data at transonic 

speeds. 

familiarization. 

USAF. Pilot familiarization in preparation for 

X-2 program. Mach 1.46 at 68 000 ft. 

NACA flight 5 1, Walker. For lateral stability and 

control data at low supersonic speeds. 

NACA flight 52, Crossfield. For wing and horizontal 

stabilizer pressure-distribution data to mach 

1.75. 

NACA flight 53, Crossfield. To gather lateral 

stability and structural loads data to mach 1.6; 

aborted when fire warning indicator came on. 

18 Mar. 1955 NACA flight 48, Crossfield. For pressure29 Apr. 

5 May 

NACA flight 49, Joseph A. Walker. Pilot 

NACA flight 50, Lt. Col. Frank K. Everest, Jr., 

6 May 

12 May 

19 May 

308 
4 Nov. 

10 Nov. 

14 Dec. 

24 Jan. 1956 

22 Mar. 

24 Aug. 

25 Sept. 

9 Oct. 

19 Oct. 

1 Nov. 

7 Nov. 

D-558 FLIGHTS 

5. D-558-2 #2, BuAer No. 37974, Flights, Continued 

Date Remarks 

8 June 1955 NACA flight 54, Crossfield. Lateral stability and 

aerodynamic loads data to mach 1.67 at 60 000 

ft. Subsequently, nozzle extensions removed 

from plane. 

NACA flight 55, Crossfield. Static and dynamic 

Stability investigation to mach 1.4. End of pressuredistribution program. Recording- manometers 

removed from aircraft. 

NACA flight 56, Crossfield. Supersonic dynamic 

stability and structural loads investigation. 

NACA flight 57, Crossfield. Same as flight 56. 

NACA flight 58, Crossfield. Same as flight 56. 

NACA flight 59, Crossfield. Same as flight 56. 

NACA flight 60, Crossfield. Same as flight 56. 

NACA flight 6 1, Crossfield. Dynamic stability 

investigation. Beginning of vertical tail-loads 

research program. One rocket cylinder failed to 

ignite, so plane limited to mach 1.25 at 40 000 ft. 

NACA flight 62, John B. McKay. Pilot familiarization, but some data on stability and control and 

tail loads taken. McKay had to use emergency 

hydraulic system to lower landing gear on this 

flight. 

NACA flight 63, Walker. Dynamic stability and 

structural loads investigation. Mach 1.34. Following this flight, nozzle extensions were again 

fitted to the LR-8 engine. 

NACA flight 64, McKay. Structural heating survey. 

NACA flight 65, McKay. Same as flight 64, mach 1.2. 

NACA flight 66, McKay. Same as flight 64, mach 

1.25. Structural heating investigation program 

canceled after this flight. 

NACA flight 67, McKay. Plane jettisoned in inflight 

emergency from B -29 (runaway prop on #4 engine). McKay jettisoned propellants and made 

safe landing on lakebed. B-29 required extensive repairs. 

NACA flight 68, McKay. Vertical tail-loads investigation to mach 1.1. 

NACA flight 69, McKay. Same as flight 68. This 

marks end of vertical tail-loads research program. 

NACA flight 70, McKay. Static and dynamic stability investigation to approximately-mach 1.5. 

NACA flight 71, McKay. Same as flight 70. 

NACA flight 72, McKay. Same as flight 70. 

NAVA flight 73, McKay. Same as flight 70. 

21 June 

1 Jul. 

20 Jul. 

3 Aug. 

12 Aug. 

24 Aug. 

2 Sept. 

16 Sept. 

309 
ON THE FRONTIER 

5. D-558-2 #2, BuAer Nu. 37974, Flights, Continued 

Date Remarks 

14 Dec. 1956 NACA flight 74, McKay. For dynamic stability data 

at mach 1.4, and to obtain overall sound-pressure levels in aft fuselage at subsonic and supersonic speeds. 

NACA flight 75, McKay. Same as flight 74. This 

was last NACA research flight on D-558-2 #2. 

20 Dec. 

6. 0-558-2 #3, BuAer No. 37975, Flights 

Date Remarks 

15 Douglas flights completed before aircraft modified to air-launch configuration. 

Eugene F. May, pilot 

8 Sept. 1950 Douglas flight 16; Bridgeman pilot, 1st airdrop. 

Flight aborted after launch, airspeed system 

malfunction. 

20 Sept. 

29 Sept. 

6 Oct. 

17 Nov. 

27 Nov. 

Douglas flight 17, Bridgeman, 2d airdrop. 

Douglas flight 18, Bridgeman, 3d airdrop. 

Douglas flight 19, Bridgeman. Airspeed calibration. 

Douglas flight 20, Bridgeman. Airspeed calibration 

and air-launch demonstration. 

Douglas flight 2 1, Bridgeman. Airspeed calibration 

and air-launch demonstration. Turbojet engine 

malfunction, premature rocket shutdown. 

Plane delivered to NACA HSFRS, designated 

NACA 145. 

NACA flight 1, A. Scott Crossfield. Pilot and instrument check, jet engine only. 

NACA flight 2, Crossfield. Same as flight 1. 

NACA flight 3, Crossfield. Slat-loads investigation 

jet only. Stalls, turns, rolls, to mach 0.7. 

NACA flight 4, Crossfield. Dynamic longitudinal 

stability investigation with slats locked to mach 

0.75; elevator and stabilizer pulses. 

NACA flight 5, Crossfield. First NACA rocket-jet 

flight. Jet engine shut off, flame instability. 

Mach 0.86 maximum. 

NACA flight 6, Crossfield. Jet only, rocket failed 

to fire, valve failure. Mach 0.84 maximum. 

NACA flight 7, Walter P. Jones, Pilot check, jet 

only. Mach 0.73. 

NACA flight 8, Crossfield. Rolls and accelerated 

turns to mach 1.14. Jet and rocket. 

NACA flight 9. Brig. Gen. Albert Boyd USAF. 

Pilot check. Jet and rocket. Mach 1.05. 

15 Dec. 

22 Dec. 

27 Dec. 

27 Mar. 1951 

20 Apr. 

17 May 

17 Jul. 

20 Jul. 

9 Aug. 

14 Aug. 

310 
D-558 FLIGHTS 

6. D-558-2 #3, BuAer No. 37975, Flights, Continued 

Date Remarks ~~~ 

22 Aug. 1951 

18 Sept. 

26 Sept. 

18 Oct. 

9 Nov. 

19 June 1952 

3 Jul. 

31 Jul. 

8 Aug. 

14 Aug. 

8 Oct. 

22 Oct. 

27 Feb. 1953 

NACA hight 10, Jones. Jet and rocket, lateral and 

longitudinal stability investigation. Aileron rolls, 

elevator pulses to mach 1.10. 

NACA flight 11, Jones. Jet only, rocket failure. 

Longitudinal stability investigation with accelerated pitching maneuver in landing configuration. Pitch-up followed by spin and normal 

recovery. 

NACA flight 12, Jones. Lateral control investigation. Jet and rocket flight to mach 0.96. Rolls, 

sideslips, elevator pulses, accelerated turns. 

NACA flight 13, Jones. Beginning of pitch-up 

investigation. Evaluation of outboard wing 

fences at mach 0.7. Fences markedly aid 

recovery. 

NACA flight 14, Jones. Same as flight 13. Mach 

0.95. Fences subsequently removed. 

NACA flight 15, Crossfield. Jet only. Pitch-up investigation with slats locked open. Mach 0.7. 

NACA flight 16, Jones. Same as flight 15. Mach 

0.96. 

NACA flight 17, Crossfield. Jet and rocket. Slat 

investigation, aborted in climb, faulty cabin 

heating. Some low-speed data. 

NACA flight 18, Crossfield. Jet and rocket. Same 

as flight 15. Mach 0.96. Inboard wing fences 

subsequently removed. Plane now in clean, nofence configuration. 

NACA flight 19, Crossfield. Slats still locked open. 

Flight to check effect of removing wing fences. 

Removal indicates inboard fences had little 

effect on aircraft behavior. Following flight, 

slats moved and locked in half open position. 

Evaluation of effect of slats half open on pitchup. Plane pitched to 36". Mach 0.97. Slats subsequently restored to free-floating condition. 

NACA flight 2 1, Crossfield. Jet and rocket. Plane 

in basic no-fence configuration. Longitudinal 

and lateral stability and control investigation. 

Pitch-ups encountered during turns. Chord 

extensions subsequently installed on outer wing 

panels. 

with chord extensions. Mach 0.7. Wing-up turns 

and I g stalls. Maneuvers terminated when decay 

in longitudinal or lateral stability became 

apparent. 

NACA flight 20, Crossfield. Jet and rocket. 

NACA flight 22, Crossfield. Jet only. First flight 

31 1 
ON THE FRONTIER 

6. 0-558-2 #3, BuAer No. 37975, Flights, Continued 

Date Remarks 

8 Apr. 1953 

10 Apr. 

15 June 

25 June 

26 June 

24 Jul. 

28 Jul. 

30 Jul. 

9 Sept. 

14 Sept. 

22 Sept. 

10 Dec. 

22 Dec. 

7 May 1954 

12 May 

2 June 

NACA flight 23, Crossfield. Jet only; rocket failed 

to fire, frozen valve. Wind-up turns, aileron rolls, 

sideslips, 1 g stalls. 

NACA flight 24, Crossfield. Jet and rocket. Mach 

1.03. Same as flight 23. Pitch-up not alleviated 

by chord extensions, so extensions removed after 

flight and slats reinstalled on wings. 

NACA flight 25, Crossfield. Jet and rocket. Slats 

locked open. Accelerated longitudinal stability 

maneuvers performed with control bungee 

installed. Decay in stability noticed at all speeds 

except at mach 1. Stiff bungee subsequently 

installed. 

NACA flight 26, Crossfield. Jet only. Slats locked 

open, stiff bungee. Airplane appeared controllable at high angles of attack; stability decay 

less objectionable. 

NACA flight 27, Stanley P. Butchart. Pilot checkout. 

Slats locked open and stiff bungee installed. Jet 

only. 

NACA flight 28, Crossfield. Jet and rocket. Plane 

in basic configuration. Transonic lateral and 

directional stability and control. Mach 1.05. 

NACA flight 29. Lt. Col. Marion Carl USMC. Pilot 

check out in D-558-2 #3 before flying allrocket D-558-2 #2. Jet power only. 

NACA flight 30, Carl. Jet and rocket. Same as 

flight 29. 

NACA flight 3 1, Crossfield. Longitudinal, lateral, 

and directional stability investigation, from 

mach 0.4 to mach 1.08. 

NACA flight 32, Crossfield. Same as flight 31. 

NACA flight 33, Crossfield. Same as flight 31. 

Because of malhnction, only 2 rocket chambers 

fired. 

NACA flight 34, Crossfield. Transonic longitudinal 

stability investigation. Turns, stalls. 

NACA flight 35, Crossfield. Same as flight 34. Jet 

only, rocket did not ignite. Plane subsequently 

modified for external-stores program. 

NACA flight 36, Joseph Walker. Pilot checkout, 

plane in basic configuration. Jet only. 

NACA flight 37, Walker. Same as flight 36. Jet and 

rocket. Mach 0.97. 

NACA flight 38, Crossfield. First flight with external stores pylons. Jet only. Evaluation of 

handling qualities to mach 0.72. 

3 12 
D-558 FLIGHTS 

6. D-558-2 #3¶ BuAer No. 37975, Flights, Continued 

Date Remarks 

16 June 1954 

8 Jul. 

19 Jul. 

23 Jul. 

28 Jul. 

9 Aug. 

11 Aug. 

18 Aug. 

30 Aug. 

8 Oct. 

21 Oct. 

23 Dec. 

28 Dec. 

27Apr. 1955 

NACA flight 39, Crossfield. First flight with external stores (1000-lb bomb shapes). Jet only. Nq 

apparent adverse effects. Mach 0.72. 

NACA flight 40, Crossfield. Jet and rocket. Stores 

decreased transonic performance and increased 

buffet. Mach 1.0. Stores shapes later removed 

as being too small. 

NACA flight 41, Crossfield. Jet and rocket. Plane in 

clean configuration. Transonic directional and 

longitudinal stability and control. Mach 1.05. 

Sideslips, elevator and rudder pulses. 

Transonic lateral stability and control investigation. Rolls from mach 0.5 to 1.05. 

NACA flight 43, Crossfield. Jet and rocket. Same as 

flight 42. Mach 1.1. 

NACA flight 44, Crossfield. Jet and rocket. 

Dynamic stability investigation from mach 0.5 to 

1.05. Elevator, aileron, and rudder pulses. 

NACA flight 45, Crossfield. Jet and rocket. Same as 

flight 44. 

NACA flight 46, Crossfield. Jet and rocket. Same as 

flight 44. 

NACA flight 47, Crossfield. Jet and rocket. Slats 

unlocked, flight for longitudinal stability and 

control and buffet characteristics of aircraft in 

this configuration. 

NACA flight 48, Crossfield. Resumption of storesinvestigation program. Handling qualities with 

150 gal tanks. Jet only. Mach 0.74. 

NACA flight 49, Crossfield. Jet and rocket. Same as 

flight 48. No adverse effects, but pilot noted 

drag rise and heavier buffet in longitudinal 

maneuvers. As a result of strain-gauge-loads 

measurements, stores program again temporarily 

suspended while Douglas checked strength 

factor of pylon and wing. 

NACA flight 50, Lt. Col. Frank K. Everest, Jr., 

USAF. Pilot checkout, jet-and-rocket flight in 

clean configuration in preparation for Bell X-2 

program. 

NACA flight 51, John B. McKay. Pilot check in 

clean configuration, jet only. 

NACA flight 52, McKay. Jet and rocket. Underwing 

pylons installed. Sideslips, rolls, elevator and 

rudder pulses. For handling qualities, wing and 

pylon loads, and buffet data. Mach 1.0. 

NACA flight 42, Crossfield. Jet and rocket. 

313 
ON THE FRONTIER 

6. D- 558- 2 #3, BuAer No. 37975, Flights, Continued 

Date Remarks 

23 May 1955 NACA flight 53, McKay. Jet and rocket, 150-gal 

stores attached. Same maneuvers as flight 52. 

Buffet levels higher with stores than with pylons 

only. 

NACA flight 54, McKay. Jet and rocket. Pylons only. 

Same maneuvers as flight 52. Mach 1.0. 

NACA flight 55, McKay. Jet and rocket. Same as 

flight 54. 

NACA flight 56, McKay. Jet and rocket. 150-gal 

stores attached. Same maneuvers as flight 52. 

NACA flight 57, McKay. Jet and rocket. Same as 

flight 56. 

NACA flight 58, McKay. Jet and rocket. Same as 

flight 56. 

NACA flight 59, McKay. Jet and rocket. Same as 

flight 56. Plane damaged on landing when tail 

cone touched lake first. 

NACA flight 60, Butchart. Jet and rocket. Same as 

flight 56. 

NACA flight 61, McKay. Jet and rocket. Same as 

flight 56. 

NACA flight 62, McKay. Jet and rocket. Same as 

flight 56. 

NACA flight 63, McKay. Jet and rocket. Same as 

flight 56. Concluded stores-investigation program. Plane returned to clean configuration. 

NACA flight 64, McKay. Jet and rocket. To obtain 

wing-loads data for comparison with externalstores data previously acquired. Lateral, 

directional, and longitudinal maneuvers. 

Mach 1.0. 

NACA flight 65, McKay. Jet and rocket. Rocket 

engine pump overspeed prevented acquisition of 

data at mach 0.9. Flight for same purpose as 

flight 64, so one more flight scheduled to 

complete research program. 

NACA flight 66, McKay. Jet and rocket. Same as 

flight 64. Mach 0.96. Completed research program on this aircraft. 

3 June 

10 June 

17 June 

24 June 

28 June 

30 Aug. 

2 Nov. 

8 Nov. 

17 Nov. 

8 Dec. 

1 Feb. 1956 

3 Feb. 

28 Aug. 

SOURCE: Hallion, Supersonic Flight, pp. 221-34. 

314 
# 

Appendix H 

X-2 Program Flight Chronology, 1954- 1956 

NACA itself never flew the X-2 research aircraft in a research program. However, 

NACA did expect to receive the aircraft following its Air Force flight test program, and 

the High-speed Flight Station supported the X-2 program with advice and data analysis. 

Two X-2 aircraft were built, the X-2 #1 (46-674) and the X-2 #2 (46-675). The 

X-2 #2 was lost in an inflight explosion while at the Bell plant in captive flight trials in 

1953. Two crewmen were killed. The X-2 #I arrived at Edwards AFB for testing in the 

summer of 1954. The following chronology is for the X-2 #1, 46-674, from 1954 

through the crash of this aircraft in 1956. It was air-launched from a modified Boeing 

B-50 Superfortress bomber. 

Bell X - 2 #I (46-674) 

Date Pilot Remarks 

25 Oct. Everest 

18 Nov. Everest 

24 Mar. 1956 Everest 

25 Apr. Everest 

1 May Everest 

11 May Everest 

22 May Everest 

5 Aug. 1954 1st glide flight. Damaged on landing. 

8 Mar. 1955 Everest 2d glide flight. Propellant system 

check. Minor damage on landing. 

6 Apr. Everest 3d glide flight. Damaged on landing. 

Following flight, plane returned to 

Bell plant for extensive modifications to landing gear system to prevent further landing accidents and 

for installation of its rocket engine. 

became 4th glide flight. 

35 000 ft. Slight fire damage from 

engine bay fire. 

mach 0.91. 

mach 1.4 at 50 000 ft. 

mach 1.683 at 53 700 ft. 

mach 1.8 at 60 000 ft. 

mach 2.53 at 58 370 ft. 

Maj. F. K. Everest 

Aborted powered flight attempt; 

1st powered flight. Mach 0.992 at 

Flight 1-56 (2d powered flight), 

Flight 2-56 (3d powered flight), 

Flight 3-56 (4th powered flight), 

Flight 4-56 (5th powered flight), 

Flight 5-56 (6th powered flight), 

315 
ON THE FRONTIER 

Bell X - 2 #I (46-674), Continued 

Date Pilot Remarks 

25 May 1956 Flight 6-56 (7th powered flight), 

pilot checkout, mach 1 + . 12 Jul. Everest Flight 7-56 (8th powered flight), 

premature engine shutdown. 

23 Jul. Everest Flight 8-56 (9th powered flight), 

mach 2.87 at 68 205 ft. 

3 Aug. Kincheloe Flight 9-56 (10th powered flight), 

mach 2.5+, 87 750 ft. 

8 Aug. Kincheloe Flight 10-56 (1 lth powered flight), 

premature engine shutdown. 

7 Sept. Kincheloe Flight 1 1-56 (12th powered flight), 

mach 1.7, reached 126 200 ft. 

27 Sept. Capt. M. Apt Flight 12-56 (13th powered flight), 

mach 3.2 at 65 500 ft. Subsequent 

loss of control from inertial coupling led to the destruction of the 

aircraft and the death of the pilot. 

Capt. I. C. Kincheloe 

SOURCE: X-2 flight progress'reports, 1954- 1956. 

3 16 
Appendix I 

X-3 Program Flight Chronology, 1954- 1956 

Following completion of contractor testing (1953) and a brief Air Force evaluation 

(1953-1954), NACA received the sole Douglas X-3 (49-2892) for testing in 1954. All 

subsequent NACA flights were piloted by High-speed Flight Station research pilot 

Joseph A. Walker. 

X - 3 Flights 

Flight Date Remarks 

1 23 Aug. 1954 Pilot familiarization. 

2 3 Sept. Static longitudinal stability and control, wing and 

3 9 Sept. Same as flight 2. 

4 9 Sept. Same as flight 2. 

5 16 Sept. Same as flight 2. 

6 19 Oct. Same as flight 2. 

7 21 Oct. Same as flight 2. 

8 21 Oct. Investigation of lateral and directional stability 

9 21 Oct. Same as flight 8. 

tail loads, and pressure distribution. 

and control. 

10 27 Oct. Same as flight 8. Aircraft experienced violent 

coupled motions during abrupt rudder-fixed 

aileron rolls at mach 0.92 and 1.05, fully demonstrating load envelope of aircraft about all 3 

axes in 1 sec. Aircraft grounded for thorough 

inspection and analysis. 

11 20 Sept. 1955 Investigation of longitudinal stability and control, 

wing and tail loads, and wing pressure 

distribution. 

12 22 Sept. Same as flight 11. 

13 6 Oct. Directional stability and control, vertical tail loads. 

14 12 Oct. Same as flight 13. Drag chute inadvertently 

15 20 Oct. Dynamic lateral stability and control, vertical 

16 21 Oct. Same as flight 15. 

17 23 Oct. 

deployed in flight without damage to aircraft. 

tail loads. 

Same as flight 15. Flight marked conclusion of 

NACA X-3 static and dynamic stability and 

control and tail loads programs on the aircraft. 

317 
ON THE FRONTIER 

X - 3 Flights, Continued 

Flight Date Remarks 

18 13 Dec. 1955 Control system evaluation. One engine damaged 

from ingestion of pressure probe; X-3 

grounded for maintenance and repairs. 

mentation compartment fire caused minor 

damage to flight-test instrumentatidn. 

Plane retired. 

19 4Apr. 1956 Pressure distribution measurements. Nose instru20 23 May Lateral control investigation; last NACA flight. 

SOURCE: X-3 flight progress reports, 1954- 1956. 

318 
Appendix J 

X-4 Program Flight Chronology, 1950- 1953 

The NACA High-speed Flight Research Station operated the Northrop X-4 #2 

(46-677) research airplane from 1950 through 1953. NACA also had the X-4 #I 

(46-676) in charge, but used it only for spares support. In cooperation with NACA, the 

Air Force Air Materiel Command ran a brief program on the craft during the summer of 

1950 before delivering it to NACA. Since NACA instrumentation was carried and data 

was collected on these flights, they were also logged as NACA test missions. 

X-4 Flights 

Flight Date Pilot Remarks 

- 2 22 Aug. 

3 22 Aug. 

4 30 Aug. 

5 31 Aug. 

6 8 Sept. 

7 

8 

9 to 

10 

11 

12 22Sept. 

13 

14 

15 

16 to 

17 

18 

19 

20 7 Nov. 

21 17 Nov. 

22 6 Dec. 

23 6 Dec. 

24 15 Dec. 

25 28 Dec. 

1 18 Aua. 1950 C. E. Yeager AF flight, pilot check. 

F. K. Everest AF flight, pilot check. 

Everest 

Everest 

Everest 

Yeager 

Yeager 

Yeager 

Yeager 

Yeager 

Yeager 

A. Boyd 

J. S. Nash 

John Griffith 

Griffith 

- 

Griffith 

Griffith 

Griffith 

Griffith 

Griffith 

R. L. Johnson 

A. S. Crossfield 

Cross field 

Cross field 

Aborted, landing gear malfunction. 

Handling qualities. 

Same as flight 4. 

Longitudinal and latitudinal stability and 

Aborted, faulty canopy lock. 

Longitudinal and latitudinal dynamic stability 

and control. 

Same as flight 8. 

Same as flight 8. 

Same as flight 8. 

AF flight, pilot check. 

Same as flight 12. 

Same as flight 12: airspeed calibration. 

First NACA pilot checkflight. 

Longitudinal, latitudinal, directional stability, 

and control. 

Same as flight 16. 

Same as flight 16. 

Same as flight 16. 

Same as flight 16. 

Same as flight 16. 

AF flight, pilot check. 

NACA pilot check; aborted. 

Aborted; instrument malfunction. 

Longitudinal, latitudinal, directional stability 

control . 

and control. 

319 
t a 

ON THE FRONTIER 

X - 4 Flights, Continued 

Flight Date Remarks 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

49 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

65 

66 

67 

68 

69 

320 

4 Jan. 1951 Crossfield 

17 Jan. Crossfield 

19 Jan. Crossfield 

24 Jan. Crossfield 

26 Jan. Crossfield 

19 Feb. 

19 Mar. 

26 Mar. 

28 Mar. 

12 Apr. 

13 Apr. 

17 Apr. 

20 Apr. 

26 Apr. 

Cross field 

Cross field 

Cross field 

Cross field 

Crossfield 

Cross field 

Crossfield 

W. P. Jones 

Cross field 

27 Apr. Jones 

3 May Jones 

9 May Cross field 

16 May Cross field 

18 May Cross field 

29 May Crossfield 

20 Aug. Jones 

2 Oct. Cross field 

5 Oct. Cross field 

9 Oct. 

11 Oct. 

12 Oct. 

17 Oct. 

18 Oct. 

19 Oct. 

24 Oct. 

6 Mar. 1952 

13 Mar. 

17 Mar. 

21 Mar. 

25 Mar. 

26 Mar. 

27 Mar. 

19 May 

Crossfield 

Cross field 

Jones 

Jones 

Joseph Walker 

Walker 

Jones 

Jones 

Jones 

Jones 

Jones 

Jones 

Jones 

S. P. Butchart 

Jones 

6 Aug. Crossfield 

11 Aug. - 16 Sept. - 

22 Sept. - 23 Sept. Cross field 

27 Mar. 1953 Crossfield 

Same as flight 25. 

Same as flight 25. 

Aborted, landing gear malfunction. 

Aborted, instrument malfunction. 

Longitudinal, latitudinal directional stability, 

and control. 

Same as flight 30. 

Same as flight 30. 

Same as flight 30. 

Same as flight 30. 

Same as flight 30. 

Same as flight 30. 

Same as flight 30. 

NACA pilot check. 

Longitudinal, latitudinal, directional stability, 

and control. 

Same as flight 39. 

Same as flight 39. 

Same as flight 39. 

Same as flight 39. 

Same as flight 39. 

Same as flight 39. 

First flight with thick trailing edge on speed 

Stability and control with thick trailing edge. 

Lift-to-drag variation using various speedbrake 

Landings at various lift-to-drag ratios. 

Same as flight 49. 

Same as flight 49. 

Constant speed-drag ratios. 

NACA pilot check; handling qualities. 

Maneuvers and speed runs. 

General stability and control. 

Lift-to-drag at various speedbrake settings. 

Directional trim change invest. 

Lift-to-drag variation with speedbrakes. 

Lift-to-drag variation studies.. 

Dynamic stability invest. 

Same as flight 60. 

NACA pilot check. 

Check flight with thickened trailing edge on 

Stability and control with thickened elevons. 

Aborted; engine malfunction. 

Aborted; instrument malfunction. 

Stability and control with thickened elevons. 

Same as flight 68. 

brakes. 

settings. 

elevons. 
X-4 FLIGHTS 

X- 4 Flights, Continued 

Flight Date Pilot Remarks 

70 29 Apr. 1953 Crossfield Airspeed calibration with thickened elevons. 

71 30 Apr. Cross field High-lift stability and control. 

72 20 May Butchart Dynamic stability without thickened elevons. 

73 1 Jul. Butchart Same as flight 72. 

74 3 Jul. Butchart Same as flight 72. 

75 - George Cooper NACA pilot check for Ames pilot. 

76 11 Aug. John McKay NACA pilot check. 

77 - Dynamic stability. 

78 to - Dynamic stability. 

79 31 Aug. - NACA pilot check. 

80 - NACA pilot check. 

81 to - NACA pilot check. 

82 (?) Sept. - Aileron pulses, low-speed turns with dive 

brakes. 

SOURCE: NACA X-4 flight reports, 1950- 1953; X-4 chronology prepared by Robert Mulac of 

Langley Research Center. 

32 1 

x 

F 
P 
? c 

Appendix K 

X-5 Program Flight Chronology, 1952- 1955 

The NACA High-speed Flight Station operated the Bell X-5 #1 (50- 1838) from 

1952 to late 1955. Following the conclusion of the contractors program in October 1951, 

the airplane was grounded for installation of a NACA instrument package. In December 

195 1, the Air Force completed a brief evaluation program involving six flights; because 

data were taken, these were considered part of the overall NACA effort and were logged 

as joint AF-NACA flights. The first all-NACA flight was flight 7, and it is with this flight 

that this chronology begins. The second X-5 (50- 1839) was operated only by Bell and 

the Air Force and was lost in a spin accident in 1953. 

Bell X - 5 #I (50-1838) Flights 

Flight Date Pilot Remarks 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

9 Jan. 1952 

14 Jan. 

21 Jan. 

23 Jan. 

25 Jan. 

1 Feb. 

5 Feb. 

12 Feb. 

4 Mar. 

13 Mar. 

17 Mar. 

19 Mar. 

19 Mar. 

20 Mar. 

27 Mar. 

1 Apr. 

3 Apr. 

29 Apr. 

2 May 

6 May 

- 

Joseph Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

- 

Walker 

Walker 

Walker 

Walker 

Walker 

A. S. Crossfield 

W. P. Jones 

Jones 

Jones 

Pilot check. 

Static and dynamic longitudinal and 

latitudinal stability and control. 

Same as flight 8. 

Airspeed calibration. 

Static and dynamic longitudinal and 

latitudinal stability and control. 

Same as flight 11. 

Same as flight 11. 

Same as flight 1 I. 

Air Force pilot check flight. 

Lateral stability at 60" sweep. 

Flight aborted. 

Latitudinal and longitudinal stability 

Airspeed calibration. 

Static and dynamic longitudinal and 

-'latitudinal stability and control. 

Gust loads investigation 20" and 60" 

sweep. 

Static longitudinal stability, 45" sweep. 

Airspeed calibration. 

Pilot check. 

Pilot check. 

Static and dynamic longitudinal and 

Same as flight 26. 

and control at 60" sweep. 

lateral stability and control. 

323 
ON THE FRONTIER 

Bell X-5 #I (50-1838) Flights, Continued 

Flight Date Pilot Remarks 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

49 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

65 

66 

67 

68 

324 

7 May 1952 

8 May 

16 May 

27 May 

28 May 

29 May 

20 June 

25 June 

26 June 

2 Jul. 

10 Jul. 

12 Jul. 

16 Jul. 

17 Jul. 

22 JuI. 

25 Jul. 

1 Aug. 

7 Aug. 

23 Sept. 

25 Sept. 

26 Sept. 

21 Oct. 

5 Dec. 

10 Dec. 

to 

18 Dec. 

22 Dec. 

8Jan. 1953 

12 Jan. 

22 Jan. 

27 Jan. 

29 Jan. 

29 Jan. 

6 Feb. 

13 Feb. 

20 Feb. 

24 Feb. 

25 Feb. 

25 Feb. 

to 

Jones 

Cross field 

Cross field 

Jones 

Jones 

Jones 

Jones 

Walker 

Walker 

Walker 

Walker 

Walker 

J. Reeder 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Cross field 

Walker 

Walker 

Walker 

S. P. Butcharl 

Butchart 

Walker 

Butchart 

Walker 

Walker 

Crossfield 

Crossfield 

Walker 

Walker 

A. Murray 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Same as flight 26. 

Same as flight 26. 

Same as flight 26. 

Same as flight 26. 

Same as flight 26. 

Aborted; gear door opened in flight. 

Static and dynamic longitudinal and 

Same as flight 34. 

Same as flight 34. 

Same as flight 34. 

Same as flight 34. 

Gust loads investigation. 

Pilot check for Langley pilot. 

Static and dynamic longitudinal and 

lateral stability and control. 

Same as flight 41. 

Static and dynamic longitudinal 

Same as flight 43. 

Static longitudinal and lateral stability 

and control. 

Lateral control, longitudinal stability. 

Static longitudinal control. 

Static longitudinal stability and 

Inadvertent spin. 

Longitudinal stability and control. 

Lateral stability and control. 

Pilot check. 

lateral stability and control. 

stability and control. 

control. 

Pilot check. 

Photographic flight. 

Aborted, inoperable stabilizer motor. 

Static and dynamic longitudinal and 

lateral stability and control. 

Vertical tail loads in maneuvers. 

Stalls and maneuvers at 20" sweep. 

Vertical tail loads in rolling pullouts. 

Drag study (ti-ailed F-80 jet). 

Drag study (trailed B-29 bomber). 

AF flight for comparison with AF X-5. 

Drag study (trailed B-29). 

Gust loads investigation. 

Gust loads investigation. 

Effect of wing translation on trim. 

Same as flight 66. 

Gust loads investigation. 
X-5 FLIGHTS 

Bell X-5 #I (50-1838) Flights, Continued 

Flight Date Pilot Remarks 

- 

69 

70 

71 

72 

73 

74 

75 

76 

77 

78 

79 

80 

81 

82 

83 

84 

85 

86 

87 

88 

89 

90 

91 

92 

93 

94 

95 

96 

97 

98 

99 

100 

101 

102 

103 

104 

105 

106 

107 

108 

109 

110 

27 Feb. 1953 

26 Mar. 

23 Apr. 

29 Apr. 

30 Apr. 

1 May 

13 May 

4 June 

3 Jul. 

21 Jul. 

27 Jul. 

28 Jul. 

30 Aug. 

25 Aug. 

27 Aug. 

28 Aug. 

4 Sept. 

12 Nov. 

16 Nov. 

14 Jan. 1954 

21 Jan. 

26 Jan. 

29 Jan. 

2 Feb. 

4 Feb. 

8 Feb. 

9 Feb. 

10 Feb. 

12 Feb. 

23 Feb. 

23 Feb. 

16 Mar. 

8 Apr. 

9 Apr. 

13 Apr. 

15 Apr. 

20 Apr. 

21 Apr. 

23 Apr. 

7 June 

11 June 

8 Dec. 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Cross field 

Cross field 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Cross field 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Walker 

Butchart 

Crossfield 

Butchart 

Iv 

Longitudinal stability and control 

Emergency landing, gear failure. 

Longitudinal stability and control. 

Same as flight 71. 

Same as flight 71. 

Same as flight 7 1. 

Strain gauge response to temperature. 

Buffet-induced tail loads. 

Wing and horizontal tail loads. 

Dynamic lateral stability. 

Aborted, cabin pressurization 

Buffet-induced tail loads. 

Buffet-induced tail loads. 

Longitudinal stability and control wing 

and tail loads. 

Same as flight 82. 

Airspeed calibration of NACA B-47. 

Pacer for NACA B-47 aircraft. 

Lateral stability and control. 

Wing twisting and bending tail loads. 

Tail loads. 

Longitudinal stability and control. 

Aborted, landing gear door malfunction. 

Lateral stability and control. 

Gust loads at various wing sweeps. 

Vertical tail loads. 

Longitudinal stability and control. 

Same as flight 94. 

Lateral stability and control at 45" and 

59", longitudinal stability and control at 59". 

wing and high tail loads. 

during wing transition. 

malfunction. 

Longitudinal stability and control, 

Dynamic pressure effects on buffet. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Same as flight 98. 

Vertical tail loads. 

Vertical tail loads. 

Instrumentation check. 

325 
* 4 0 rz 

ON THE FRONTIER 

Bell X-5 #I (50-1838) Flights, Continued 

Flight Date Pilot Remarks 

111 

112 

113 

114 

115 

116 

117 

118 

119 

120 

121 

122 

123 

124 

125 

126 

127 

128 

129 

130 

131 

132 

133 

14 Dec. 1954 

to 

27 Jan. 1955 

28 Jan. 

3 Feb. 

3 Feb. 

21 Feb. 

23 Feb. 

8 Mar. 

21 Mar. 

23 Mar. 

23 Mar. 

1 Apr. 

5 Apr. 

6 Apr. 

to 

8 Apr. 

to 

25 Oct. 

- 

- 

- 

B utc hart 

Butchart 

Butchart 

Butchart 

Butchart 

Butchart 

John McKay 

McKay 

McKay 

Butchart 

McKay 

Butchart 

McKay 

McKay 

- 

N. A. Armstrong 

Pilot check. 

Pilot check. 

Pilot check. 

Pilot check. 

Instrumentation check. 

Longitudinal stability and control. 

Longitudinal stability and control. 

Longitudinal stability and control. 

Longitudinal stability and control. 

Longitudinal and lateral stability and 

Longitudinal stability and control. 

Longitudinal stability and control. 

Longitudinal stability and control. 

Lateral stability and control. 

Lateral stability and control. 

Lateral stability and control. 

Lateral stability and control. 

Lateral stability and control. 

Lateral stability and control. 

Lateral control. 

Lateral control. 

Lateral control. 

Pilot check. Landing gear door 

control. 

separated in flight. Plane subsequently was retired. 

SOURCE: NACA X-5 flight reports, 1952-1955; X-5 chronology prepared by Robert Mubdc of 

Langley Research Center. 

326 
Appendix L 

XF-92A Program Flight Chronology, 1953 

NACA flight-tested the Convair XF-92A (46-682) during 1953. This program followed earlier flight testing of the aircraft by Convair and the Air Force 1948-1953. 

Project pilot for the NACA tests was High-speed Flight Research Station research pilot 

A. Scott Crossfield. 

XF - 92A Flights 

Flight Date Remarks 

1 9Apr. 1953 Pilot check; static longitudinal stability 

2 16 Apr. Static and dynamic stability and control. 

3 21 Apr. Longitudinal stability and control. 

4 27 May Longitudinal stability and control. 

5 3 June Lateral and directional stability and control. 

6 5 June Longitudinal stability and control. 

7 9 June Longitudinal stability and control. 

8 11 June Longitudinal stability and control. 

9 16 June Longitudinal stability and control. 

10 19 June Longitudinal stability and control. 

11 24 June Longitudinal stability and control. 

12 24 June Longitudinal stability and control. 

13 26 June Low-speed stability and control. 

14 3 Jul. First flight with wing fences. 

15 3 Jul. Second fence flight. 

16 22 Jul. Modified fence design; fences buckled in flight. 

17 17 Aug. Engine malfunctioned, aborted flight. 

18 20 Aug. Longitudinal stability and control with modified 

19 20 Aug. Same as flight 18. 

20 30 Sept. Low-speed lateral and directional control with 

fences. 

21 30 Sept. Same as flight 20. 

22 2 Oct. Same as flight 20. 

23 5 Oct. Same as flight 20. 

24 14 Oct. Low-speed lateral and directional control without 

25 14 Oct. 

investigation. 

fence design. 

fences. 

Same as flight 24. Nose landing gear collapsed 

during landing rollout. Plane was retired. 

SOURCE: XF-92A flight progress reports, 1953. 

327 

c 

329 

IIIIIIIIII 
ON THE FRONTIER 

Illlllltllll 

IIIIIIIIIIII 

0 

CD 

2 

d 

%J 

2 4 

Y 

0 

Y L m 

iz 

IIIIIIIIIIII 
$i s 

X-15 FLIGHTS 

000 om0 

-me 

mo* 

mmm 

Ill 

2zw 

000 

000 ma0 

w-- 

Ill 

omm om0 

mom m*m 

Ill 

*ma *** 

G 

c 

M 

a 

a" 

3 

m 

e 

M 

Y .- -* 

.e 

111111111111 .. 000000000000 

000000000000 moomr-**wwar-rmo*r-aoomm*am 

222g3r-222232 

IIIIIIIIIIII Ill 

mar - m - - 

0-m 

aaa 

33 1 
w r 

ON THE FRONTIER 

I I I I I I I 00~0000 

0000000 wmm*wmo 

IIIII 

00000 

00000 r-ffio*m 

I IIIIIII IIII Ill IIIIIII IIIII 

I IIIIIII Ill IIIIIII 

*Or- 

-mmar. 

r-r-r332 
X-15 FLIGHTS 

IIIIII 

000000 

000000 w*mmmo 

IIIIIIIII 

000000000 

000000000 mw*ommocDo 

IIIIIIIIIII 

IIIIII IIIIIIIIIII 

333 
ON THE FRONTIER 

IIIIIII 

3000000 

3000000 X)mcDm*mm 

IIIIIII 
e. I P 0 

X- 15 FLIGHTS 

000 

n-m 

mmm 

3mWbm 

Ill 

000 

000 

mOW 

WWO 

Wmrmm 

IIIII Ill 

m*m 

222 

Li Li 

P P 

0 

m 

W 

0 

m 

I 

0 

0 * 

W 

W 

b 

0 

n 

m 

I 

I 

* 

m * 

3 

3 

5 

m 

x ; 

63 

0 

I 

m 

W 

I 

3 

1 

(0 

W 

in, 

x 

3 

W 

b 

2 

00000000000 

00000000000 o~nwobo~omm 

oWm3Om33wbo 

-mm-mmwm- ~OO**mmmbmo 

335 
R I! e 

ON THE FRONTIER 

c, 

IIII 

, 

1 

1 

C 
IIIIIIII 

omd3CDwmo22222222 

IIIIIIII d3mabwmobbbbbbWt0 

IIIIIIII 

W 

X-15 FLIGHTS 

337 
a 
;h 

a 

0 

a 
ON THE FRONTIER 

222222222 

IIIII1III 

000000000 

000000000 

000000000 

mmmmmmmmm ********* 

000000 mmbCNmm 

*bObr.CN 

222222 

IIIIII 

000000 mo*ooo 

*ObOOM, 

Q, 

CD 

2 
P c * 1 

LIFTING-BODY FLIGHTS 

s 

a 

24 

... 0000 

0000 

bbW0 

0 

b 

34 1 
ON THE FRONTIER 

m 

0 

m 

m 

0 

oo 

I 

I 

m 

0 

m 

* 

r: 

2 

2 

I 

t0 

0 

0 

m * 

M 

ld 

; 

m 

m 

I 

w 

m 

I 

5, 

0 

r2 

2 

1 

L-r 

3 

3 

a 

a 

IIII 

0000 

0000 

*0COm 

. . . . . . . 0000000 

0000000 0003mmm 

342 
c 

c 

a 

& 

4 

.z E 

71 

1- 

Y 

0 r= 

a 

e, 

Y 

d 

4i 

c 

bn 

e, 

a 

- 9 

a a a * 

LIFTING-BODY FLIGHTS 

m 

b 

4i 

c 

bo 

e, 

M 

a 

9 

e 

E 

- 

Y 

00 

2R 

22 

II 00 

00 

00 

Om ** 

343 
* 

ON THE FRONTIER 

IIIIIII 

mQ,cnmmwQ, 

r: '9 '4 9 '4 9 

4 

0000000 mmmwwmQ, r-bb0or-m 

2222222 

IIIIIII 

ooo**o* 

ooorooon ooobroon 

mmmmmmo ***ma*a 

';r 

rQ, 

In 

rQ, 

344 
000000 

m0.ILNGvmo.I 

r.r.r.r.r.r. 

222222 

IIIIII 

8 00000 

000000 

00000 

mmmmmm ***-e** 

R * ? 

LIFTING-BODY FLIGHTS 

345 

Appendix 0 

XB - 70A Program Flight Chronology, 1967 - 1969 

FRC operated the XB-70A #1 (62-0001) aircraft from 1967 through early 1969. 

This aircraft was the sole survivor of two prototypes. The second aircraft (62-0207) was 

destroyed in a mid-air collision on 8 June 1966. By this time, both aircraft had 

accumulated a total of 95 flights, 49 by #I, and 46 by #2. 

A joint Air Force-NASA program began in November 1966 and lasted through 

January 1967. The all-NASA program (with Air Force support) began with the 107th 

flight of the XB-70A series, on 25 April 1967. Because the XB-70A #1 formally began its 

NASA research career at that point, that flight has been chosen to head this chronology. 

XB - 70A Flights 

Flight Date PilodCopilo t Remarks 

107 (1-61) 

108 (1 -62) 

109 (1-63) 

110 (1-64) 

111 (1-65) 

112 (1-66) 

113 (1-67) 

114 (1-68) 

115 (1-69) 

116 (1-70) 

117 (1-71) 

118 (1-72) 

119 (1-73) 

25 Apr. 1967 

12 May 

2 June 

22 June 

10 Aug. 

24 Aug. 

8 Sept. 

11 Oct. 

2 Nov. 

12 Jan. 1968 

13 Feb. 

28 Feb. 

21 Mar. 

Cotton/Fulton Flight aborted after crew entry 

door opened and landing 

gear malfunctioned. 

airspeed calibration. 

Fulton/Cotton Low-speed handling qualities; 

Cotton/Van Shepard Mach 1.43; handling qualities. 

FultodDonald Mallick Pilot checkout; mach 1.83. 

Cotton/Col. E. Pilot checkout; mach 0.92 

Sturmthal 

FultodMallick Mach 2.24 at 17 600 m. 

CottonISturmthal Mach 2.3; inlet studies. 

FultodMallick Mach 2.43 at 17 700 m. 

Cotton/Sturmthal Mach 2.55; inlet studies, longitudinal handling qualities. 

Fulton/Mallick Mach 2.55 at 20 400 m; stability 

and control. 

MallicMCotton Mach 1.18; handling qualities. 

Fulton/Sturmthal Landing gear malfunction. 

Cotton/Fulton Gear-down, low-speed studies. 

347 
t m c a Y 

ON THE FRONTIER 

XB - 70A Flights, Continued 

Flight Date PilotlCopilot Remarks 

120 (1-74) 11 June 1968 MallicWFulton Landing gear malfunction. 

121 (1-75) 28 June SturmthaYCotton Mach 1.23, structural dynamics. 

122 (1-76) 19 Jul. Mallic WFulton Mach 1.62, structural dynamics. 

123 (1-77) 16 Aug. FultodSturmthal Mach 2.47, structural dynamics. 

Inlet unstart, loss of #6 

engine. 

124 (1-78) 10 Sept. MallicMFulton Mach 2.5 at 19 140 m. 

125 (1-79) 18 Oct. SturmthaYFulton Mach 2.18, structural dynamics. 

126 (1-80) 1 NOV. SturmthaYFulton Mach 1.62, structural dynamics, 

127 (1-81) 3 Dec. Fulton/Mallic k Mach 1.64, same as flight 126. 

128 (1-82) 17 Dec. FultonlSturmthal Mach 2.53, same as flight 126. 

129 (1-83) 4 Feb. 1969 Fulton/Sturmthal Subsonic, ferry flight to USAF 

stability and control. 

Museum, Wright-Patterson 

AFB, Dayton, Ohio. 

XB - 70A Program Summary 

Total Flights 

By XB-70A #1 83 

By XB-70A #2 46 

Total Flying Time (both aircraft): 252 hours 38 minutes 

Total time above mach-1: 55 hours 50 minutes. 

Total time above mach 2: 49 hours 32 minutes. 

Total time above mach 3: 1 hour 48 minutes. 

SOURCE: XB-70A program flight chronology, prepared by the DFRC Pilots Office. 

348 
Appendix P 

YF- 12 Program Flight Chronology, 1969- 1978 

The NASA YF- 12 program flew three aircraft, YF- 12A #60-6935 (935), YF- 12A 

#60-6936 (936), and YF- 12C #60-6937 (937). YF- 12A 936 completed 62 flights, primarily by Air Force flight test crews, before being lost in an inflight fire on 24 June 1971. 

The Air Force crew ejected safely. 

NASA's program on the YF- 12A and'YF- 12C aircraft lasted from 1969 through 1978. 

The first NASA flight was on 5 March 1970, when test pilot Fitzhugh L. Fulton piloted 

YF- 12A 936 on a checkout flight. He followed this with flights on 9 March and 1 1 March. 

NASA's first flight in YF- 12A 935 was by Donald Mallick on 1 April 1970. The first NASA 

flight in YF- 12C 937 was by Fitzhugh L. Fulton on 24 May 1972. 

The FRC flight crews for the YF- 12 were pilots Fitzhugh Fulton and Donald Mallick, 

and flight-test engineers Victor Horton and Ray Young. Before retirement, aircraft 935 

was used to check out other center pilots on familiarization flights. 

YF - 12A 935 Flights 

Flight Date PilodTest Engineer Remarks 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

1 1 Dec. 1969 

17 Dec. 

6 Jan. 1970 

14 Jan. 

19 Jan. 

21 Jan. 

27 Jan. 

11 Feb. 

26 Mar. 

1 Apr. 

8 Apr. 

14 Apr. 

17 Apr. 

28 Apr. 

1 May 

7 May 

Col. J. Rogers/ USAF test. 

Maj. W. Campbell/ USAF test. 

Maj. G. Heidlebaugh 

Maj. S. Uriini 

Rogers/Ursini 

Campbell/ 

Col. Slated 

Slater/Ursini 

Slater/Heidlebaugh 

CampbelllUrsini 

Campbell/ 

Victor Horton 

Donald MallicW 

Ursini 

Mallic WUrsini 

Fitzhugh Fultonl 

FultordHorton 

MallicWRay Young 

Fulton/Horton 

Mallic WYoung 

Heidlebaugh 

Heidlebaugh 

Horton 

USAF test. 

USAF test. 

USAF test. 

USAF test. 

USAF test. 

Ventral fin damage in sideslip. 

First flight with NASA engineer. 

First flight of 935 with NASA 

pilot. 

Mach 2, air refueling. 

Mach 2. 

349 
8 b 

ON THE FRONTIER 

YF - 12A 935 Flights, Continued 

Flight Date PilodTest Engineer Remarks 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

49 

50 

51 

52 

15 May 1970 

22 May 

27 May 

2 June 

11 June 

16 June 

22 March 1971 

7 Apr. 

16 Apr. 

29 Apr. 

5 Nay 

23 June 

9 Jul. 

13 JuI. 

20 Jul. 

27 Jul. 

3 Aug. 

10 Aug. 

17 Aug. 

22 Oct. 

22 Oct. 

29 Oct. 

29 Oct. 

2 Nov. 

9 Nov. 

16 Nov. 

23 Nov. 

30 Nov. 

7 Dec. 

7 Dec. 

14 Dec. 

21 Dec. 

11 Jan. 1972 

18 Jan. 

26 Jan. 

26 Jan. 

FultodHorton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

FultontYoung 

Mallic WHorton 

Fulton/Horton 

Fulton/Horton 

MallicWYoung 

Fulton/Horton 

Mallic WY oung 

Fulton/Horton 

Mallic WYoung 

Mallic WHorton 

Mallic WHorton 

Lt. Col. R. J. Layton/ 

Fulton/Horton 

Fulton/Horton 

Mallic WHorton 

Ful ton/Horton 

Young 

MallicWHorton 

Fulton/Young 

MallicWHorton 

Fulton/Young 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Young 

Fulton/Horton 

Mach 1.5 phugoid investigation. 

Phugoid investigation. 

Same as flight 18; mach 2. 

“Engine problems.” 

Intercept of YF- 12A 936. Following flight, 935 grounded 

for instrumentation changes. 

Ventral fin removed following 

flight to assess performance 

of p!ane without ventral fin. 

Ventral off. 

Ventral off. 

Ventral off; 2 unstarts. 

Ventral off. Mach 2.8. Ventral 

First flight with ventral backon. 

installed after this flight. 

Hydraulic systems failureabort. 

Ferry from Palmdale. 

Loads, handling qualities, airSame as flight 49. 

Same as flight 49. 

Same as flight 49. 

frame-propulsion interactions. 

350 
YF- 12 FLIGHTS 

YF - 12A 935 Flights, Continued 

Flight Date Pilot/Test Engineer Remarks 

53 23 Feb. 1972 MallicEdYoung Refuel over El Paso for max. 

time at mach 3; 2 hr 30 min 

flight. Following this flight, 

aircraft was grounded for 

more than a year for studies 

in FRC heat loads laboratory. 

tory. 

54 First flight since loads labora55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

65 

66 

67 

68 

69 

70 

71 

72 

73 

74 

75 

76 

77 

78 

79 

80 

81 

82 

83 

84 

85 

86 

87 

88 

89 

* 90 

12 Jul. 1973 

26 Jul. 

3 Aug. 

23 Aug. 

6 Sept. 

13 Sept. 

11 Oct. 

11 Oct. 

23 Oct. 

7 Nov. 

16 Nov. 

3 Dec. 

13 Dec. 

11 Jan. 1974 

17 Jan. 

25 Jan. 

4 Mar. 

8 Mar. 

15 Mar. 

21 Mar. 

28 Mar. 

18 Apr. 

2 May 

16 May 

23 May 

30 May 

6 June 

11 Sept. 

17 Sept. 

3 Oct. 

18 Oct. 

25 Oct. 

1 Nov. 

7 Feb. 1975 

14 Feb. 

27 Feb. 

9 yay 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Young 

Mallic WHorton 

Fulton/Horton 

Mallick/Larry Barnett 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

FultodYoung 

Mallic WYoung 

Mallic WYoung 

Fulton/Horton 

Fulton/Horton 

FultordHorton 

Fulton/Horton 

Fulton/Horton 

FultonNoung 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

Mallic WYoung 

KC- 135Q tanker malfunction. 

Aborted after takeoff. 

First “coldwall” experiment. 

Second coldwall. 

Plane shed ventral at mach 0.9; 

landed safely, grounded for 

repairs. No ventral until #97. 

35 1 
ON THE FRONTIER 

YF- 12A 935 Flights, Continued 

Flight Date Pilot/Test Engineer Remarks 

91 

92 

93 

94 

95 

96 

97 

98 

99 

100 

10 1 

102 

103 

104 

105 

106 

107 

108 

109 

110 

111 

I12 

113 

114 

115 

116 

117 

118 

119 

120 

121 

122 

123 

124 

11 Jul. 1975 

24 Jul. 

7 Aug. 

21 Aug. 

28 Aug. 

5 Sept. 

16 Jan. 1976 

27 Jan. 

5 Feb. 

12 Feb. 

4 Mar. 

23 Mar. 

2 Apr. 

12 Apr. 

13 May 

20 May 

15 Jul. 

22 Jul. 

10 Aug. 

31 Aug. 

13 Sept. 

28 Sept. 

21 Oct. 

10 Nov. 

9 Dec. 

3 Mar. 1977 

2 June 

23 June 

21 Jul. 

30 Sept. 

13 Oct. 

18 Nov. 

1 Dec. 

1 Dec. 

FultodHorton 

Mallic WYoung 

FultodHorton 

Ful todHorton 

Mallic WYoung 

FultodHorton 

Mallic WYoung 

Ful ton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Young 

Fulton/Horton 

Fulton/Young 

Fulton/Young 

Mallic WYoung 

Fulton/Horton 

Mallick/Young 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Horton 

Fulton/Horton 

Fulton/Horton 

Fulton/Horton 

Mallic WYoung 

FuIton/Horton 

Fulton/Horton 

Fulton/Horton 

Fulton/Horton 

FultonlHorton 

Fulton/Horton 

MallicWYoung 

John Manke/Horton 

William Dana/Horton 

Third coldwall flight. Mach 2.4. 

Fourth coldwall flight. Mach 

Fifth coldwall flight. 

Flowfield studies stability and 

Same as flight 94. 

Stability and control investiFirst flight with Lockalloy 

Landing-gear taxi tests. 

Landing-gar taxi tests. 

Lockalloy ventral check flight. 

Same as flight 100. 

Same as flight 100. 

Same as flight 100. 

Same as flight 100. 

“High-speed flight.” 

Completed ventral testing. 

Ventral and coldwall envelope 

Coldwall envelope studies 

Coldwall profile “hot” data. 

Same as flight 109. 

Skin-friction cooling studies. 

Continued “hotwall” data study. 

Coldwall insulation prematurely 

blew off experiments at mach 

3. 

2.4. 

control. 

gation. 

ventral. 

check. 

complete. 

Gust probe calibration. 

Hotwall data. 

Coldwall experiment. 

Coldwall experiment. 

Coldwall experiment. 1st “good 

Bad unstarts on flight. 

Coldwall flight. 

Final coldwall-good results. 

Boundary layer and handling 

qualities studies. 

Pilot familiarization, mach 3. 

Pilot familiarization. 

flight. 

352 
125 

126 

127 

128 

129 

130 

131 

132 

133 

134 

135 

136 

137 

138 

139 

140 

141 

142 

143 

144 

145 

146 

15 Dec. 

14 Dec. 

28 Feb. 1978 

28 Feb. 

7 Mar. 

7 Mar. 

15 Mar. 

15 Mar. 

23 Mar. 

31 Mar. 

31 Mar. 

2 Nov. 

1 Dec. 

24 Jan. 1979 

16 Feb. 

8 Mar. 

15 Mar. 

28 Mar. 

28 Mar. 

31 Oct. 

7 Nov. 

YF- 12 FLIGHTS 

YF- 12A 935 Flights, Continued 

Flight Date PilotlTest Engineer Remarks 

9Dec. 1977 Gary Krierhoung Pilot familiarization. 

E. Enevoldson/Y&ng Pilot familiarization. 

T. McMurtry/Horton Pilot familiarization. 

MallicWYoung Landing-gear-system taxi tests. 

Mallic WYoung Landinggear taxi tests. 

Fulton/Horton Landing-gear taxi tests. 

Fulton/Horton Landing-gear taxi tests. 

MallickJYoung Landing-gear taxi tests. 

MallicWYoung Landing-gear taxi tests. 

FuIton/Horton 

landing program. 

EnevoldsonlYoung Same as flight 134. 

DandHorton Same as flight 134. 

FultodHorton Shaker vane study. 

Fulton/Horton Shaker vane study. 

MallicMYoung Shaker vane study. 

Fulton/Horton Shaker vane study. 

Mallic WYoung Shaker vane study. 

Fulton/Horton Shaker vane study. 

Stephen Ishmael/ 

Michael Swann/Horton Pilot familiarization. 

Fulton/Horton Last NASA flight. 

Col. J. Sullivan/ 

Tests in support of Shuttle 

Pilot familiarization, mach 3. 

Horton 

Ferry to USAF Museum, 

Col. R. Uppstrom Wright-Patterson AFB, 

(USAF crew) Dayton, Ohio. 

YF-12C 937 Flights 

Flight Date PilodTest Engineer Remarks 

1 

2 

3 

4 

5 

6 

7 

8 

16 Jul. 1971 

24 May 1972 

6 June 

14 June 

21 June 

18 JuI. 

26 Jul. 

1 Aug. 

Air Force crew 

Fultonr’Horton 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

FultonlY oung 

Mallic WYoung 

FuIton/Horton 

Delivery to FRC. 

First NASA flight by 937. 

Airspeed calibration. 

Propulsion studies for baseline 

data, stability and control. 

Same as flight 5. 

Same as flight 5; phugoid study. 

Same as flight 5. Target for 

F- 14 intercept trials. 

353 
c e * 

ON THE FRONTIER 

YF - 12C 93 7 Flights, Continued 

Flight Date PilodTest Engineer Remarks 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

43 

34 

35 

36 

37 

38 

39 

40 

41 

42 

15 Aug. 1972 

22 Aug. 

29 Aug. 

15 Nov. 

22 Nov. 

5 Dec. 

12 Dec. 

11 Jan. 1973 

18 Jan. 

24 Jan. 

1 Feb. 

8 Feb. 

15 Feb. 

22 Feb. 

22 Mar. 

5 Apr. 

12 Apr. 

20 Apr. 

26 Apr. 

2 May 

3 May 

10 May 

17 May 

31 May 

8 June 

11 Jul. 

26 Jul. 

13 Sept. 1974 

25 Sept. 

7 Nov. 

19 Dec. 

19 Dec. 

17 Jan. 1975 

24 Jan. 

Mallic WYoung 

Ful tonNoung 

MallickNoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Fulton/Young 

MallicWHorton 

FultonlYoung 

Mallic WHorton 

Mallic WHorton 

MallicWHorton 

Fulton/Young 

Mallic WYoung 

Fulton/Horton 

Mallick/Young 

MallicWYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Mallic WYoung 

Mallic WYoung 

FultodHorton 

Mallic WYoung 

Mallic WYoung 

Fulton/Horton 

Mallic WHorton 

Airspeed lag calibration, 

stability and control. 

Navigation equipment failure. 

Experienced fuel leak. 

Unstart propulsion tests. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion studies. 

Propulsion and jet wake 

Propulsion studies, F- 14 

Propulsion studies, F- 14 

Propulsion studies, F- 14 

Propulsion studies, F- 14 

Stuck inlet spike caused high 

dispersion. 

target. 

target. 

target. 

target. 

fuel consumption and 

emergency landing at Fallon 

NAS, Nev. 

NAS. 

Subsonic ferry from Fallon 

Propulsion studies. 

Propulsion studies. 

Handling qualities. 

Propulsion studies. 

Propulsion studies. 

Performance studies. 

Performance studies. 

Performance studies. 

Performance studies. 

354 
4 

YF- 12 FLIGHTS 

YF - 12C 93 7 Flights, Continued 

Flight Date PilodTest Engineer Remarks 

43 

44 

45 

46 

47 

48 

49 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

65 

66 

67 

68 

69 

70 

71 

72 

73 

74 

75 

76 

77 

78 

79 

24 Apr. 1975 

5 June 

12 June 

20 June 

26 June 

3 Jul. 

7 Aug. 

14 Aug. 

11 Sept. 

14 Sept. 

16 Oct. 

30 Oct. 

16 Sept. 1976 

30 Sept. 

21 Oct. 

9 Nov. 

19 Nov. 

2 Dec. 

3 Mar. 1977 

18 Mar. 

24 Mar. 

I Apr. 

12 May 

19 May 

26 May 

2 June 

15 June 

16 June 

23 June 

14 Jul. 

21 Jul. 

8 Sept. 

16 Sepe. 

22 Sept. 

30 Sept. 

13 Oct. 

26 May 1978 

Fulton/Horton 

Mallic WYoung 

FultodHorton 

Mallic WYoung 

Fulton/Horton 

Mallic WYoung 

Mallic WYoung 

MallicWYoung 

Mallic WYoung 

Fulton/Horton 

MallicWYoung 

Fulton/Horton 

MallicWYoung 

MallicWYoung 

Mallic WYoung 

MallicWHorton 

Mallic WY oung 

MallicWYoung 

Mallic WYoung 

FultonlHorton 

Fulton/Young 

Mallic WHorton 

FultonlHorton 

Mallic WYoung 

Fulton/Horton 

Mallic WY oung 

Mallic WYoung 

Fulton/Horton 

MallicWYoung 

FultodHorton 

Mallic WYoung 

Mallic WYoung 

Fulton/Horton 

MallicWYoung 

Mallic WYoung 

MallicWYoung 

Mallic WYoung 

Performance studies. 

Propulsion studies. 

Chase for 935, propulsion 

Propulsion studies. 

Propulsion studies. 

Engine stalls study. 

Engine stalls study. 

Boattail drag study. 

Boattail drag study. 

Chase for 935. 

Inlet studies. 

studies. 

Chase for 935, inlet studies. 

Chase for 935 coldwall. 

Inlet studies. 

Airframe-propulsion interactions. 

Chase for 935 coldwall. 

Inlet studies, interactions. 

Chase for 935; bad unstarts. 

Interactions. 

Interaction. 

Interaction. 

Chase for 935 coldwall. 

Chase for final 935 coldwall. 

Following this flight, the aircraft was grounded for modifications to begin a “co-op” 

control program. 

Checkout of digital computer 

system. 

355 
c c 

ON THE FRONTIER 

YF - 12C 937 Flights, Continued 

Flight Date Pilot/Test Engineer Remarks 

80 16 June 1978 Fulton/Horton Digital computer system check. 

81 17 Jul. Mallic WYoung Digital computer system check. 

82 3 Aug. Fulton/Horton Computer checkout. 

83 18 Aug. MallicUYoung Computer checkout. 

84 31 Aug. Fulton/Horton Computer checkout. 

85 7 Sept. Mallic WYoung Co-op control test. 

86 13 Sept. Fulton/Horton Co-op control test. 

87 25 Sept. Fulton/Horton Co-op control test. 

88 28 Sept. MallicldYoung Co-op aborted. Final NASA 

89 27 Oct. J. Sullivan/ Transfer flight to USAF. 

Maj. W. Frazier (AF) 

90 22 Dec. Lt. Col. C. JewetdFrazier Last flight of aircraft. 

Aborted flight. 

flight. 

-~ 

Total Flights 

YF- 12 Program Summary 

By YF- 12A 935: 146 

By YF- 12A 936: 62 

By YF-12C 937: 89 

Total Flying Time (935 plus 937) 

Approximately 450 flight hours. 

Total Flying Time at or above mach 3 

Approximately 37 flight hours. 

SOURCE: YF- 12 program flight requests, information supplied by flight crews, information from 

the files of Richard Klein, Gene Matranga, Ming Tang, and Paul Reukauf, DFRC. 

356 
a * a a 

Appendix Q 

Space Shuttle Orbiter Approach and Landing 

Tests Program Flight Chronology, 1977 

During 1977, in conjunction with the NASA Johnson Space Center, DFRC undertook verification testing of the Space Shuttle’s approach and landing behavior. 

Tests air-launched the Space Shuttle orbiter OV- 101, Enterprise, from a modified 

Boeing 747-100 jet transport. The approach and landing test (ALT) program was 

intended to certify the low-speed airworthiness of the Shuttle orbiter, as well as its 

pilot-guided and automatic approach and landing capabilities. For this reason, the 

Enterprise differed in a number of respects from a Shuttle ready for orbital spaceflight. 

During the testing, the Enterprise was fitted with a drag-reducing and airflow-smoothing 

tailcone. Subsequently, two glide flights were made without the tailcone and with the 

Shuttle’s engine installation simulated so as to acquire data more closely approximating 

the Shuttle’s configuration when returning from orbit. 

The ALT program had three phases: a captive inactive phase with the Enterprise 

unmanned and with its systems inert; a captive active phase, with the Enterprise piloted 

and all systems operational; and, finally, a free-flight test phase, with the Enterprise 

actually launched in flight from the back of the 747 aircraft becoming, in effect, the 

worlds largest glider. 

SPACE SHUTTLE ORBITER OV-101, ENTERPRISE 

I. Captive Inactive Tests 

Flight Date Crew Duration Remarks __ -~ 

2 hrs 5 rnin 462 kph (287 mph) at 

4900 m (16 000 ft) 

1 18 Feb. 1977 - 

2 22 Feb. 

3 25 Feb. 

4 28 Feb 

5 2 Mar. 

- 3 hr 13 rnin 528 kph (328 mph) at 

- 2 hr 28 rnin 684 kph (425 mph) at 

- 2 hr 11 rnin 684 kph (425 mph) at 

- 1 hr 39 rnin 763 kph (474 mph) at 

6900 m (22 600 ft) 

8100 m (26 600 ft) 

8707 m (28 565 ft) 

9100 m (30 000 ft) 

357 
4 d 

ON THE FRONTIER 

II. Captive Active Tests 

During this test phase, the Enterprise was crewed on each flight by a team of 

astronauts-either Fred Hake and Charles Fullerton or Joseph Engle and Richard Truly. 

Haise was a former FRC research pilot; Engle had flown the X- 15 at the center as well. 

Flight Date Crew Duration Remarks 

1 18 June 1977 Haise/Fullerton 55 min 45 sec 335 kph (208 mph) at 

2 28June EngleITrul y 1 hr 2 min 499 kph (310 mph) at 

4563 m (14 970 ft) 

6715 m (22 030 ft) 

3 26 July Haise/Fullerton 59 min 53 sec 502 kph (312 mph) at 

8532 m (27 992 ft) 

4 Canceled as unnecessary. 

III. Free-Flight Tests 

Dura- Tail- Launch Launch Landing 

Flight Date Crew tion cone Altitude Speed Speed 

1 12Aug. 1977 H/F 5-21 On (24 100 ft) 500 kph 343 kph 

2 13 Sept. E/T 5-28 On (26 000 ft) 498 kph 359 kph 

3 23 Sept. H/F 5-34 On (24 700 ft) 463 kph 354 kph 

4 12 Oct. E/T 2-34 Off (22 400 ft) 445 kph 369 kph 

5 26 Oct. HIF 2-01 Off (19 000 ft) 454 kph 350 kph 

(min-sec) 

(270 knots) (185 knots) 

(269 knots) (194 knots) 

(250 knots) (191 knots) 

(240 knots) (199 knots) 

(245 knots) (189 knots) 

Crew: HIF = HaiseIFullerton. E/T = EngleKruly. 

Launch altitude: altitude at separation from 747. 

SOURCE: NASA release 77-224; NASA, Space Shuttle Orbiter Approach and Landing Test: Finul Report 

(Washington, DC: NASA, Feb. 1978). 

358 
Appendix R 

Accident Statistics, 1954- 1975 

Number of Accidents 

Calendar Year Accidents Flight Hours Total Flights 

1954 

1955 

1956 

1957 

1958 

1959 

1960 

1961 

1962 

1963 

1964 

1965 

1966 

1967 

1968 

1969 

1970 

1971 

1972 

1973 

1974 

1975 

1 

1 

1 

0 

0 

1 

0 

0 

3 

0 

0 

0 

1 

2 

8 

0 

0 

0 

0 

0 

0 

0 

346 

52 1 

469 

41 1 

508 

532 

685 

672 

1016 

1806 

1747 

1833 

1493 

1731 

1963 

1887 

1736 

1777 

1868 

1675 

1585 

1679 

376 

52 1 

46 1 

463 

448 

520 

695 

650 

926 

1472 

N/A 

N/A 

1258 

1430 

1496 

1688 

1596 

16 13 

1571 

1459 

1327 

1474 

Accident Rate 

Period Rate per 100 000 Rate per 100 000 

Flight Hours Flights 

197 1 - 1975 0 0 

1966- 1970 34.1 40.2 

1961 - 1965 42.4 N/Ad 

1956- 1960 76.8 77.3 

1954 - 1955 230.7 223.0 

"Data lacking for total number of flights in 1964 and 1965. 

SOURCE: DFRC Safety Office files. 

359 
ON THE FRONTIER 

1962 

1962 

1966 

HSFSIFRCIDFRC Flight Accidents 

Calendar Year Aircraft Remarks 

1948 Douglas D-558- 1 Engine failure on takeoff. 

1953 Convair XF-92A Landing gear failure on 

Howard Lilly killed. 

rollout after landing. 

Aircraft retired. 

after emergency landing. 

Minor damage to aircraft. 

lamch. Plane jettisoned, 

destroyed. 

gear collapse. Plane 

damaged. 

damaged beyond repair. 

failure, followed by 

tailskid collapse on 

landing. Pilot Jack 

McKay seriously injured; 

plane virtually destroyed 

but rebuilt as X- 15A-2. 

Pilot undershot landing 

at Norton AFB; plane 

damaged beyond repair. 

flap deployment caused 

uncontrollable rolling. 

Pilot Milton Thompson 

ejected safely. 

XB-70A #2. Pilot Joseph 

Walker killed, as was 

XB-7OA copilot. Both 

aircraft lost. 

Bruce Peterson seriously 

injured; plane rebuilt as 

M2-F3. 

1954 North American F- lOOA Collision with hangar 

1955 Bell X- 1A Inflight explosion before 

1956 Bell X- 1E Landing accident; nose1959 North American F- 107A Takeoff accident. Plane 

1962 North American X- 15 #2 Inflight powerplant 

Inflight asymmetric 

Mid-air collision with 

1967 Northrop M2-F2 Landing accident. Pilot 

1967 North American X- 15 #3 Break-up during reentry; 

pilot Michael Adams 

killed. 

Lockheed T-33A 

Lockheed F- 104A 

Lockheed F- 104N 

- ~~ 

SOURCE: DFRC Safety Office files. 

360 
A Note on Sources 

The majority of sources cited in this study are records such as 

memorandums, policy statements, progress reports, and planning documents found within Record Group 255, Records of the National Advisory Committee for Aeronautics and the National Aeronautics and Space 

Administration, maintained by the National Archives and Records Service. 

Many other documents are in the files of Dryden Flight Research Facility; 

at other NASA centers such as Ames, Langley, and Johnson; and in the 

possession of present and former employees. Other sources include 

documents held by the USAF Systems Command Historical Office, and 

the Historical Office of the USN’s Naval Air Systems Command. Finally, 

some documentation was provided by individuals at major aircraft and 

aerospace manufacturing concerns such as McDonnell Douglas, Rockwell, 

and Lockheed. 

As with other aspects of aviation history, there are few useful 

published sources dealing with the subjects discussed in this work; 

indeed, only one previous book had dealt with the origins of supersonic 

flight in America, and that by the author of this study. The lack of 

published works dealing with the development of postwar aerospace 

technology and the management and utilization of that technology can be 

taken as a general indication of the future studies that are required to 

enhaqce our understanding of the impact and role that aviation and 

aerospace science have had upon modern society. 

The following discussion of sources useful to this study should 

indicate the scope of records available to a researcher examining other 

aspects of NACA-NASA history as well. 

My research began in the NASA History Office at NASA Headquarters, Washington, D.C. The History Office provided great assistance over 

a number of years, both on this topic and others. The History Office 

archives consist of 500 cubic feet of records, with another 395 cubic feet 

stored at the Federal Records Center at Suitland, Maryland. The series 

that contain information useful to this study are: Congressional Documents, Industry, Organization and Management, Budget Documentation, 

NASA Headquarters, NASA Centers, Manned Space Flight, Tracking 

and Data Acquisition, Biography File, and Aeronautics. 

The Dryden Flight Research Center records are retired to the Federal Records Center, Laguna Niguel, California. (Previously, they were at 

36 1 
ON THE FRONTIER 

the Federal Records Center at Bell, California.) Record Group 255 boxes 

that proved of particular value at Bell are 310 and 312 (X- 1 reports), 

321 (X-2 documentation), and 361, 362, and 366, all on the D-558 

program. The files of the NASA Langley Research Center contain much 

useful material on the early days of Dryden when it operated as a satellite 

of Langley, including the annual and semiannual reports of the NACA 

Research Airplane Projects Panel and the NACA High-speed Flight 

Station. The retired records of Ames Research Center at the Federal 

Records Center at San Bruno, California, contain documentation pertaining to Ames’s role in Dryden’s affairs during the 1940s and 1950s. The 

Lyndon B. Johnson Space Center’s History Office maintains a large collection of records on manned spaceflight. This was particularly useful for 

the Space Shuttle project and its origins. 

Since Dryden operates as a tenant on Edwards Air Force Base, Air 

Force records reveal the nature of the relationship between the service 

and this civilian agency. Particularly pertinent are the semiannual and 

annual historical reports submitted to higher command concerning the 

activities of the Air Force base. These reports, including primary 

documents in appendixes, are on file at Edwards, but copies are also held 

by the Air Force Systems Command History Office at Andrews AFB, 

Maryland, and at the Albert F. Simpson Historical Research Center, 

Maxwell AFB, Alabama. Though Dryden’s connections with naval aviation never equaled those with the Air Force, there was a significant 

interchange of ideas between the Navy and Dryden especially in the 

1940s and 1950s. The files of the Naval Air Systems Command contain 

memorandums and reports of the Bureau of Aeronautics. 

This history could not have been prepared without the cooperation 

and assistance of a number of persons, especially the staff of the Dryden 

center itself. Many preserved key documents over the years, and these 

were made available to the author. More important, however, many of 

the staff consented to interviews, as did many former NACA, NASA, Air 

Force, Navy, and industry officials. These interviews provided insight 

into the human story of Dryden-the working of the staff, viewpoints 

and goals, what individuals felt they had accomplished. While oral history 

is no substitute for written records, it is a supplement that can flesh out 

and elaborate on the more traditional sources. 

What remains to be done? Dryden’s story offers a view of a unique 

research center operating at the forefront of technological change in a 

critical period of aeronautical and astronautical development. We have 

seen the emergence of aerospace technology. In many sections of the 

manuscript, the fulfillment of that technological promise is alluded to. 

Further study is indicated on the supersonic breakthrough and the turbojet revolution and their impact on modern business, industry, transportation, military affaip, and society as a whole. We are an aerospace society and need to understand what this means to us and to our descendants. 

362 
n 

Source Notes 

Chapter 1 

1. See John V. Becker, The High-speed Frontzer: Case Histories of Four NACA Programs, 1920- 1950, 

NASA SP-445 (Washington, DC: NASA, 1980); Richard P. Hallion, Supersonic Flight: Breaking 

the Sound Barrier and Beyond, The Story of the Bell X- 1 and Dough 0-558 (New York: The 

Macmillan Company, 1972); Charles Burnet, Three Centuries to Concorde (London: Mechanical 

Engineering Publications Limited, 1979); Jay Miller, The X Planes: X-1 to X- 29 (St. Croix, 

MN: Specialty Press, 1983.) 

2. The detailed evolution and subsequent employment of the XS-1 and the D-558 series is 

related in Hallion, Supersonzc Flaght, passim. 

3. Ltr., Reid to NACA Hq., 29 Dec. 1945, office files of Robert W. Mulac, NASA LaRC; interview 

with Walter C. Williams, 13 June 1977, and subsequent Williams comments to author. 

4. Interview of Walter C. Williams by Eugene M. Emme, 25 Mar. 1964, on file with the NASA 

History Office. 

5. Williams interview, and DFRC chronology in the DFRC External Affairs Office, files of Ralph 

B. Jackson. 

6. A good introductory history of telemetry is found in Wilfred J. Mayo-Wells, “The Origins of 

Space Telemetry,” in Eugene M. Emme, ed., The History of Rocket Technology: Essays on Research, 

Development, and Utzlzty (Detroit: Wayne State University Press, 1964), pp. 253-268. 

7. Statement of Walter C. Williams at the History Session, Annual Meeting of the American 

Institute of Aeronautics and Astronautics, San Francisco, California, 28 Jul. 1965. Copy in the 

files of the NASA History Office. 

8. Interview with Katherine H. Armistead, 10 Dec. 1976. 

9. Williams interview; NACA High-speed Flight Station, “10th Anniversary Supersonic Flight,” 

X-Press (14 Oct. 1957), pp. 1, 4, 11-14. 

10. R. M. Stanley and R. J. Sandstrom, “Development of the XS-1 Airplane,” in Air Force 

Supersonic Research Airplane X S - I Report No. 1,9 Jan. 1948, pp. 15-16. Copy in NASA History 

Office files. 

Ltr., J. W. Crowley to B/G A. R. Crawford, 19 Feb. 1947, in NASA LaRC files. 

Williams interview; interview with Gerald M. Truszynski, 21 May 1971; interview with De E. 

Beeler, 1 Dec. 1976. 

Hartley A. Soul6, Memo for Chief of Research (NACA), “Army proposal for accelerated tests of 

the XS-1 to a Mach number of 1.1,” 21 Jul. 1947, in NASA LaRC files; Charles E. Yeager, 

“The Operation of the XS- 1 Airplane,” in Azr Force Supersonic Research Azrplane XS-1 Report 

No. I, p. 17; and Walter C. Williams, “Instrumentation, Airspeed Calibration, Tests, Results 

and Conclusions,” in Air Force Supersonic Research Airplane XS-I Report No. I, pp. 21 -22. 

14. Ltr., Herbert Hoover to Melvin Gough, 22 Aug. 1947, in LaRC files. 

15. Williams interview; conversation with Walter Diehl, 26 Mar. 1976; interview with Milton Ames, 

26 Jul. 1971. 

16. Confidential source. 

17. HSFS, “10th Anniversary Supersonic Flight,” X-Press (14 Oct. 1957), p. 3. 

18. Charles E. Yeager, “Flying Jet Aircraft and the Bell XS- 1,” in Walter J. Boyne and Donald S. 

Lopez, The Jet Age: Forty Years of Jet Aviation (Washington, DC: Smithsonian Institution Press, 

1979), pp. 107- 108. 

Ltr., John P. Mayer to Michael Collins. 8 Sept. 1976; copy in author’s files. 

Williams interview and subsequent conversations; William R. Lundgren, Across the High Frontier: 

The Story of a Test Pilot: Major Charles E. Yeager, USAF (New York: William Morrow & Co., 1955), 

pp. 224-235; Hallion, Supersonic Flight, pp. 107- 108; Tom Wolfe, The Right Stuff (New York: 

Farrar, Straw, Giroux, 1979), p. 57. Wolfe is not reliable for details on the flight itself, however. 

11. 

12. 

13. 

19. 

20. 

363 
a 

NOTES TO PAGES 17-33 

2 1. Williams interview; Lundgren, Across the High Frontier, pp. 236-240; Hallion, Supersonic Flight, 

p. 108. 

22. Details of flight are from Yeager’s pilot report, now on loan from the Historical Office, Air 

Force Flight Test Center, and on exhibit in the Flight Testing Gallery of the National Air and 

Space Museum, Smithsonian Institution, Washington, DC. 

23. Williams interview and subsequent conversations. 

24. Hoover pilot report, 16 Dec. 1947. 

25. Williams interview; ltr., Hoover to Cough, 17 Sept. 1947, in NASA LaRC files; Itr., Edmond C. 

Buckley to Hartley A. Soul&, 22 Jan. 1948. 

26. XS-1 progress reports submitted by Hubert M. Drake and Hal R. Goodman to Hartley A. 

Soul6 for 9 Dec. 1947, 12 Mar‘. 1948,29 Mar. 1948, and 13 Apr. 1948. Chronology of rocket 

research aircraft flights prepared by Robert W. Mulac of the Langley Research Center; copy on 

file with the NASA History Office. 

Hartley A. Soulk, “Review and Status of Research Airplane Program” (summary report of 

Research Airplane Projects Panel, 1949), p. 11, copy in author’s files. 

27. 

28. Ibid., p. 12. 

Chapter 2 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

14. 

15. 

16. 

17. 

18. 

19. 

20. 

Armistead interview. 

Beeler interview. 

This and subsequent Buckley quotes are from a letter, Edmond C. Buckley to Hartley A. Soul6, 

22 Jan. 1948. 

Ltr., Walter C. Williams to Col. Signa A. Gilkey 9 Mar. 1948. 

H. J. E. Reid, Memo for files, 18 Mar. 1948, NASA LaRC files. 

Williams interview; ltr. and attachment, Smith J. De France to J. W. Crowley, 5 May 1948, 

NASA ARC files. 

Details on the earlier squabble may be found in Alex Roland‘s history of the NACA, Model 

Research: The NationalAduisory Committee for Aeronautics, 1915-1958 (NASA SP-4103), in press. 

Williams interview; Jean R. Hailey, “Maj. Gen. Albert Boyd, 69, Dies: Father of Modern Flight 

Testing,” The Washington Post, 22 Sept. 1976. 

Ltr., Chief, Navy Bureau of Aeronautics to NACA Hq. and BuAer representative, Douglas 

Aircraft Corporation, 4 Nov. 1947, Aer-AC-25, in historical files of Naval Air Systems Command. 

D-558-1 progress reports by William H. Barlow for 8 Dec. 1947, 18 Jan. 1948, 2 Feb. 1948, 

13 Feb. 1948,2 Mar. 1948,29 Mar. 1948, 13 Apr. 1948, 12 May 1948; Mulac flight chronology. 

Details from M. N. Cough, A. Young, and H. A. Goett, Amraft Accident Investigation Report 

Douglas 0-558-1 Airplane, BuNo 37971, Muroc Air Force Base, Muroc, California, May 3, 1948 

(Hampton: NACA LMAL, 1948), passzm. 

Ames interview; Williams interview and subsequent conversations; Edwin P. Hartman, Adventures in Research: A History of Ames Research Center, 1940-1965, NASA SP-4302 (Washington, 

Interview with Robert A. Champine, 11 Nov. 1971. 

Wallops’ extensive and important activities in relation to the X-series research airplane 

program and the DFRC are reviewed in Joseph Adams Shortal, A New Dimension: Wallops Islund 

Flight Test Range: The First Fzfteen Years, Reference Publication 1028 (Washington, DC: NASA, 

1978). The Wallops station made two important contributions to the X-series program early in 

its development: discovering a so-called aileron reversal problem on the Bell X-2, and 

discovering a directional instability problem on the X-3. Both discoveries forced needed 

redesign of the craft. 

Ltr., Crowley to NACA laboratories, 9 Aug. 1948, NASA LaRC files. 

Ltr., Soul6 to NACA Hq., 30 Aug. 1948, NASA LaRC files. 

Ltr., Ira Abbott to Soul6, 2 Sept. 1948, NASA LaRC files. 

Ltr., Soul6 to Williams, 9 Sept. 1948, NASA LaRC files. 

Becker, The High-speed Frontier, p. 90. 

Ibid., p. 118. 

DC: NASA, 1970), pp. 168-169. 

364 
NOTES TO PAGES 33-58 

21. DRFC chronology, in the files of the DFRC External Affairs Office; NACA, Thirty-SWth Annual 

Report of the NACA: 1950 (Washington, DC: NACA, 1951), p. 68; Williams interview and 

subsequent conversations. 

22. Becker, The High-speed Frontier, pp. 92-93. 

23. Soulc?, “Review and Status of Research Airplane Program,” pp. 13- 14. 

24. Douglas Aircraft Company, Summa9 Report US. Nq Transonic Research Project Douglas Model 

D-558, Rept. E. S. 15879,31 Aug. 1959,pp. 22,50-51, in the files of the historian, Naval Air 

Systems Command. 

25. Williams interview and subsequent conversations; “DRB” [Donald R. Bellman], Status of 

Research with the 0-558-1 Ai@um, 14 Sept. 1950, pp. 3-4. 

26. Williams’ comments to author upon reviewing earlier draft; in author’s notes. 

27. Champine interview; D-558-2 progress reports for 15 Aug. 1949 and 14 Nov. 1949; Mulac 

D-558-2 flight chronology. 

28. Ltr., Williams to Soult, 16 May 1949, NASA LaRC files. 

29. IM. 

30. Ltr., Williams to Soult, 12 Oct. 1949; Mulac, X-4 flight chronology. 

31. Becker, The High-speed Frontier, pp. 98-113, 183; Hallion, Supersonic Flight, pp. 193-195; 

interview with John Becker, 12 Nov. 1971. 

32. Becker, The High-Speed Frontier, p. 95. 

Chapter 3 

1. AFFTC History Office, History of the Air Force Flight Test Center, July 1 -Dec. 31, I965 (Edwards 

AFB: AFFTC, 1966), pp. 17, 22-23, and 30, in the files of the AFFTC History Office. 

2. Jane Van Nimmen and Leonard C. Bruno, with Robert L. Rosholt, NASA Historical Data Book, 

1958-1968, v. 1: NASA Resources, NASA SP-4012 (Washington, DC: NASA, 1976), pp. 

271-78. 

NACA, Thzrty-seventh Annual Report of the NACA: 1951 (Washington, DC: NACA, 1952), pp. 

53-54; Walter C. Williams, “A Brief History of the High-speed Flight Station,” Jul. 1956, p. 6, 

copy in the files of the NASA History Office. 

4. Ltr., Soul6 to NACA Hq., 19 Apr. 1954; ltr., E. H. Chamberlin to NACA Langley Laboratory, 5 

Apr. 1954; Williams, “A Brief History of the HSFS,” p. 6. 

5. Williams’ comments to author. 

6. This discussion of pitch-up is based on interpretation of flight test reports from the Skyrocket, 

X-5, and XF-92A programs, as well as from Robert L. Carroll, The Aerodynamics of Powered 

Flight (New York: John Wiley & Sons, Inc., 1960), p. 171; and Daniel 0. Dommasch, Sydney S. 

Sherby, and Thomas F. Connolly, Airplane Aerodynamics: Fourth Editzon (New York: Pitman 

Publishing Corporation, 1967), pp. 432-433,467-476. 

X-5 pilot report by Joe Walker, 31 Mar. 1952, NASA LaRC files. 

Recollection of Walter C. Williams in conversation with author. 

In 1949, Hartley SoulP, with the assistance of NACA-USAF liaison officer William J. 

Underwood emphatically stated this viewpoint in refuting allegations by the Air Force Aircraft 

Laboratory at Wright Field that the X-5 was an unnecessary duplication of the XF-92A delta 

program-a strange charge, and puzzling considering that the strongest X-5 supporters 

were Air Force partisans who felt its development should be accelerated to provide a lightweight 

export fighter. Military interest in the X-5 was, not surprisingly, always oriented toward 

applications, not research. See letter, Hartley A. Soult to Hugh L. Dryden, 29 Nov. 1949, 

NASA LaRC files. 

10. Mulac X-5 chronology; summary of X-5 monthly progress reports, in the files of the DFRC. 

11. Summary of X-4 monthly progress reports in DFRC files. 

12. Williams interview and subsequent comments. 

13. Summary of XF-92A monthly progress reports in DFRC files; Mulac, XF-92A chronology. 

14. Summary of X-3 monthly progress reports in DFRC files; Mulac X-3 chronology; Williams 

comments to author. 

15. HSFS, NACA Research Memorandum RM-H55A 13, “Flight Experience with Two High-speed 

Airplanes Having Violent Lateral-Longitudinal Coupling in Aileron Rolls,” NASA HSFS, 4 

Feb. 1955, passim; Walker pilot report, in DFRC files. 

3. 

7. 

8. 

9. 

365 
NOTES TO PAGES 59-75 

16. NACA TN- 1627, “Effect of Steady Rolling on Longitudinal and Directional Stability” (1948). 

17. Walter C. Williams and Hubert M. Drake, “The Research Airplane: Past, Present, and Future,” 

Aeronautical Engineering Review (Jan. 1958), pp. 38-39; HSFS annual report to the RAPP for 

1956, p. 3, copy in NASA LaRC files. 

HSFS annual report to the RAPP for 1954, in NASA LaRC files; progress reports for the 

D-558-2 #3, May 1954-Sept. 1956; Mulac D-558-2 chronology; Williams comments to 

author. 

19. The most conciseand damning-example of NACA criticism is a letter from Lockheed 

designer Clarence “Kelly” Johnson to Milton B. Ames, 21 Oct. 1954. Johnson himself was a 

master of blending the research and operational aspects of a program into a single airframe 

(for example, the P-80, U-2, and later SR-71). However, his F-104 was heavily dependent 

upon the X-3 for its aerodynamic shape, performance analysis, and other matters, disproving 

his general contentions in the letter. A RAND Corporation study of Lockheed F-104 

development concluded that: 

18. 

The F- 104 history illustrates that research and development in one program can have 

a great carry-over value in another. Lockheed’s success in building and flying a 

prototype less than a year after go-ahead would very probably not have been possible 

without the knowledge derived from the Douglas X-3 program. Although the value of 

this experimental effort in the F- 104 effort could hardly have been anticipated when 

Air Force money was advanced to finance the program, nevertheless the value to the 

Air Force of the X-3 program extended far beyond the immediate results achieved 

with it. 

Thomas A. Marschak, The Role of Project Histories in the Study of R €3 D (Santa Monica: The RAND 

Corporation, Jan. 1964), pp. 85-86,90. 

20. For example, a proposed Convair interceptor powered by a combined rocket-ramjet engine 

and launched from a take-off dolly. 

21. Melvin B. Zisfein, a member of the F- 104 design staff, clearly remembers the enthusiasm with 

which Lockheed designers welcomed the latest development reports on the X-3 from the 

NACA. Conversation with the author. 

CHAPTER 4 

1. Various D-558-2 #2 progress reports, Dec. 1950-Aug. 1951 in NASA LaRC files; the Douglas program is discussed from Bridgeman’s perspective in William Bridgeman and Jacqueline 

Hazard, The Lonely Sky (New York: Henry Holt and Co., 1955), passim; see also Hallion, Supersonic 

Flight, pp. 154-159. 

2. Frank E. Everest as told to John Guenther, The Fastest Man Alive (New York: Pyramid Books, 

1959), p. 129. 

3. Williams conversation with author. 

4. Crossfield’s role in orchestrating the mach 2 attempt is highlighted in A. Scott Crossfield with 

Clay Blair, Jr., Always Another Dawn: The Story of a Rocket Test Pilot (New York: The World 

Publishing Company, 1960), pp. 167- 169. See also Mulac, D-558-2 flight chronology. 

5. Crossfield and Blair, pp. 168- 169. Williams conversation. 

6. Crossfield and Blair, pp. 171- 178; James A. Martin, “The Record Setting Research Airplanes,” 

Aerospace Engineering (Dec. 1962), p. 51. 

7. Edwards AFB Historical Report, 1 July-31 Dec. 1953, in the files of Air Force Systems Command Historical Office, Andrews AFB; HSFRS annual report to the RAPP for 1953, p. 3. 

8. Details on Yeager’s flight are from ltr., Yeager to author, 12 Oct. 1971; RM-H55G25, passim; 

Lundgren, Across the High Frontier, pp. 278-284; and the HSFRS annual report to the RAPP for 

1953, pp. 3-4. 

9. Flight and accident details are from NACA HSFS, “Report of Investigation into the Loss of the 

X- IA Research Airplane on August 8, 1955,” Nov. 1955, copy in DFRC safety office files. 

10. Zbid.; interview with Donald R. Bellman, 4 Mar. 1977. 

11. Zbid. (both). 

12. Everest and Guenther, pp. 197-211; Crossfield and Blair, pp. 149-152, 213. 

366 
NOTES TO PAGES 76-92 

13. Everest and Guenther, pp. 21 1-218; interview with Richard Day, 24 Feb. 1977; Richard Day 

and Donald Reisert, “Aerodynamics Section: History of Events Prior to the X-2 Flight of 

September 27, 1956,” X - 2 Accident Investigation (Edwards: HSFS, 17 Oct. 1956), pp. 1-2; 

Williams interview and subsequent conversations. 

14. Day interview; Day and Reisert, pp. 1-2. 

15. Ronald Stiffler, The Bell X - 2 Rocket Research Aircraft: The Flight Test Program (Edwards: AFFTC, 

12 Aug. 1957), pp. 61-62. 

16. I. C. Kincheloe, “Flight Research at High Altitude, Part 11,” Proceedings of the Seventh AGARD 

General Assembly, the Washington AGARD conference, 18-26 Nov. 1957; Stiffler, pp. 70-72; 

James J. Haggerty, Jr., First of the Spacmn: Iven C. Kincheloe, Jr. (New York: Duell, Sloan and 

Pearce, 1960), pp. 107-121. 

17. Memo, Richard E. Day to Walter Williams, 28 Sept. 1956. 

18. Stiffler, pp. 81-82; Day memo to WCW Day and Reisert, pp. 1-2. 

19. Stiffler, pp. 81-82; Day and Reisert, pp. 1-2; Haggerty, pp. 122-133. 

20, Stiffler, p. 87. 

21. Crypt0 message, Crowley to WCW, 2 Oct. 1956; crypto message, Williams to Dryden, 28 Sept. 

1956; ltr., Williams to Dryden, 3 Jan. 1957; memo, Day to Williams, 2 Nov. 1956; Williams 

interview and subsequent conversations. 

22. Stiffler, p. 28. 

23. Stiffler, p. 30. 

24. Richard D. Banner, NACA Research Memorandum RM-H57D18b, “Flight Measurements of 

Airplane Structural Temperatures at Supersonic Speeds,” NACA HSFS, 7 June 1957; X- 1B 

Progress reports, Oct. 1955 to Jan. 1957; Mulac, X-1B flight chronology. 

25. Wendell H. Stillwell, X - I5 Research Results (Washington, DC: NASA, 1965), p. 26. 

26. Interview with Neil A. Armstrong, 26 Jan. 1972; X-1B progress reports, June 1957 to June 

1958; Hubert M. Drake, “Flight Research at High Altitude, Part I,” Proceedings of the Seventh 

AGARD General Assembly, the Washington AGARD Conference, 18-26 Nov. 1957. 

27. Interview with Gene Matranga, 3 Dec. 1976; Williams and Drake, “The Research Airplane,” pp. 

36-41; X- 1E progress reports, 1955- 1958 inclusive. 

28. Applicability of growth and trend curves to the study of technological questions and as exploratory forecasting methods is examined by Joseph P. Martino, “Survey of Forecasting Methods, 

Part I,” World Future Society Bulletin (Nov.-Dec. 1976), pp. 4-7. 

29. Williams and Drake, “The Research Airplane,” pp. 36-41. 

30. Becker, The High-speed Frontier, p. 95. 

CHAPTER 5 

1. A comprehensive collection of HSFRS correspondence between NACA Hq., other NACA centers, 

the Air Force, and Northrop on the F-89 is in the records collection of the Ames Research 

Center, held by the Federal Archives and Records Center, San Bruno, California. 

2. For example, see Henry A. Cole, et al., NACA Technical Report TR 1330, “Experimental and 

Predicted Longitudinal and Lateral-Directional Response Characteristics of a Large Flexible 35“ 

Swept-Wing Airplane at an Altitude of 35 000 Feet” (Washington, DC: NACA, 1957). See also 

Williams, “A Brief History of the High-speed Flight Station,” p. 6; NHSFRS annual report to the 

RAPP for 1953 (pp. 14,43) and 1954 (pp. 11-12,42); Hartman, Adventures in Research, p. 261. 

3. Edwards AFB historical chronology, in the files of the AFFTC History Office; Mulac, KC-135 

flight chronology; memos, Glenn H. Robinson to Walter 6. Williams, 6 Dec. 1957,27 Dec. 1957, 

and 5 Mar. 1958. 

4. F- 100 and YF- 102 development is summarized by Marcelle Size Knaack in Encyclopedia ofthe 

US. Air Force Aircraft and Missile Systems, v. I, Post-World War II Fighters, 1945 - 1973 (Washington, 

DC: USAF, 1978), pp. 113-133, 158-173. 

5. Everest, The Fastest Man Alive, pp. 12- 13, 19-20. 

6. Williams interview and subsequent conversations. 

7. HSFS report to the RAPP for 1954, p. 37. Mulac F-100A flight chronology; Crossfield and 

Blair, Always Another Dawn, p. 198. 

367 
c * 

NOTES TO PAGES 92- 110 

8. 

9. 

10. 

11. 

12. 

13. 

14. 

15. 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

Mulac, F- IOOA and F- IOOC flight chronology; RAPP meeting minutes, 4-5 Feb. 1957; Armstrong interview; Williams interview and subsequent conversations. 

Williams, “A Brief History of the High-speed Flight Station,” p. 7; Mulac, YF- 102 and F- 102A 

flight chronologies; Matranga interview; Armstrong interview. 

Mulac, F- 104A flight chronology; Finch interview. 

Matranga interview; Finch interview; conversations with Michael Collins, Milton Thompson, 

and Thomas McMurtry, 5 Jan. 1978; Mulac, F-104A flight chronology; Thomas W. Finch, 

“Briefing on the NACA F- 104A Roll-Coupling Program Presented to Wright Air Development 

Center and Lockheed Aircraft Corporation Personnel,” 21 Oct. 1957. 

Mulac, F- 107A chronology; Bellman interview; Matranga interview; interview with William 

Dana, 3 Dec. 1976. 

Williams interview and subsequent conversations. 

HSFS annual report to the RAPP for 1954, p. 12; Crossfield and Blair, pp. 194- 199. 

Mulac F- 104A chronology; interview with Milton Thompson, 5 Jan. 1978. 

CHAPTER 6 

NACA HSFS, Review of Aeronautical Research, HSFS (HSFS, n.d.) in the files of the office of the 

Deputy Director, DFRC. 

I6d. 

See NASA Office of Aeronautics and Space Technology, OAST Research Centers: Charter, 

Contributions, Resources-A Foundatton for Institutional Planning (Washington, DC: NASA, Sept. 

Williams and Drake, “The Research Airplane: Past, Present, and Future,” p. 40. 

Williams interview and subsequent conversations; Van Nimmen and Bruno, NASA Histurical 

Data Book, v. I, p. 271; Robert L. Rosholt, An Administrative Hktory of NASAJ958-1963, NASA 

SP-4101 (Washington, DC: NASA, 1966), p. 79. 

Data are from Van Nimmen and Bruno, section on FRC. 

Arnold S. Levine, “An Administratzve History of NASA, 1963-1969” (draft ms.), NASA Historical 

Office, 23 Aug. 1977, p. 96. 

OAST, OAST Research Centers, pp. 3- 1 to 3-3. 

John V. Becker, “The X- 15 Program in Retrospect,” RaFmfuhrtforschung (March-April 1969), p. 

45. The study in question was E. Singer and I. Bredt, “Uber einen Raketenantrieb fur Fernbomber, 

Deutsche Luftfahrtforschung UM 3538 (Ainring: Deutsche Forschungsanstalt fur Segelflug, 

1944). 

1973), pp. 3- 1 to 3-3. 

10. NACA Aerodynamics Committee meeting minutes, 4 Oct. 1951; 30 Jan. 1952; 24 June 1952; 

NASA LaRC staff report, “Conception and Research Background of the X- 15 Project” 

(Hampton: LaRC, June 1962), pp. 2-4; Hubert Drake and L. Robert Carman, “A Suggestion of 

Means for Flight Research at Hypersonic Velocities and High Altitudes“ (Edwards: HSFS, n.d.); 

D. G. Stone to F. L. Thompson, 21 May 1952; NASA LaRC staff report (draft), “History of 

NACA-Proposed High Mach Number, High-Altitude Research Airplane” (Hampton: LaRC, 

n.d.), p. 2, in files of NASA History Office; Hubert M. Drake and L. Robert Carman, “Suggested 

Program for High-speed High-Altitude Flight Research” (Edwards: HSFS, Aug. 1953); Douglas 

Aircraft Company, Summary Report for Contract Nmb 1266(00), “High Altitude and High 

Speed Study” (El Segundo: Douglas Aircraft Company, 28 May 1954); ltr., Edward H. Heinemann 

to author, 10 Feb. 1972; Thomas A. Sturm, The USAF Scientific Advisory Board: Its First Twenty 

Years, 1944-1964 (Washington,, DC: USAF, 1 Feb. 1967), p. 59; John V. Becker, “The X-15 

Project,” Astronautics &? Aeronautics (Feb. 1964), pp. 52-61. 

11. Becker interview. 

12. LaRC, “Conception . . .,” pp. 5- 12; Robert S. Houston, Development of theX-15 Research Aircraft, 

1954-1959, v. 111 of Histmy of Wright Air Developnent Center, 1958 (Wright-Patterson AFB: 

WADC, June 1959), pp. 3-9; Aerodynamics Committee minutes, 5 Oct. 1954; Becker, p. 47; 

interview with Benjamin S. Kelsey, 15 Mar. 1978; memorandum of understanding: “Principles 

for the Conduct by the NACA, Navy, and Air Force of a Joint Project fot a New High Speed 

Research Airplane,” sgnd. 23 Dec. 1954, copy in NASA History Offie files. 

13. Becker interview. 

14. Houston, pp. 9-20; Becker interview; review of Bell, Douglas, Republic, and North American 

368 

proposals; LaRC, “Conception.. .,” pp. 25-54. 
NOTES TO PAGES 1 1 1 - 128 

15. Truszynski interview; interview with K. C. Sanderson, 3 Mar. 1977; “NASA Aerodynamic Test 

Range” (Edwards: DFRC, n.d.), pp. iii-iv, 1 - 1; Houston, pp. 173- 174; Stillwell, X-19 Research 

Results, pp. 41 -44; Van Nimmen and Bruno, p. 273; USAF Air Force Systems Command, System 

Package Program for X-15A Research Airmft System 653A, 18 May 1964, p. 3-5. 

16. Mulac, X-15 flight chronology; Crossfield and Blair, pp. 307-366. 

17. Mulac, X- 15 flight chronology; Crossfield and Blair, pp. 366-405; NASA, X- 15 series flight 

log assembled by Betty J. Love, NASA DFRC. 

18. Stillwell, p. 65. Stillwell’s book is useful mostly for the information on the program prior to 1965. 

Interview with R. Dale Reed, 30 Nov. 1976. 

19. Becker, “The X-5 Program in Retrospect.” See also Stillwell, p. 66; and James E. Love, “X- 15: 

Past and Future,” paper presented to the Fort Wayne Section, Society of Automotive Engineers, 

9 Dec. 1964. 

20. Stillwell, pp. 51 -52,75-78; for a general technical review of the X- 15 effort, seeJoseph Weil, 

NASA Technical Note D-1278, Review of the X-15 Program (Washington, DC: NASA, June 

1962); Becker, “The X- 15 Program in Retrospect.” 

21. Stillwell, p. iv; see also Walter C. Williams, “The Role of the Pilot in the Mercury and X-15 

Flights,” Proceedings of the Fourteenth AGARD General Assembly, 16- 17 Sept. 1965, Portugal. 

22. We& Review ofthe X-15 Program; James E. Love and W. R. Young, “Operational Experience 

from the X- 15 Program,” n.d., files of the DFRC Safety Office. 

23. Betty Love, X- 15 flight chronology, DFRC Pilots’ Office files. 

24. Love, ”X- 15: Past and Future”, Becker, “The X- 15 Program in Retrospect”, memo on X- 15 

foUow-on program by Homer Newell to Hagh Dryden, 18 Dec. 1961; undated memo, Bikle to 

Soul6 (believed Nov. 1961); memo, Stack to Dryden, 3 Jan. 1962; ltr., Dryden to Maj. Gen. 

Marvin C. Demler, USAF, 12 Jul. 1962; NASA news release 61-261. 

25. Air Force Systems Command, X- 15 System Package Program, 6-37-48; Love, “X- 15: Past and 

Future”; ltr., Dryden to Demler, 23 Mar. 1962; NASA news release 62-98; X- 15 news release 

62-91; ltr., Dryden to Lt. Gen. James Ferguson, 15 Jul. 1963; NASA news release 64-42; 

Carlton R. Gray, MITIIL X- 15 Horizon Definition Experament Final Report (Cambridge, Mass.: 

MIT Instrumentation Laboratory, Oct. 1969), passim.; NASA George C. Marshall Space Flight 

Center news release 68-69. 

26. AFSC, X-15 System Package Program, 1-2; Robert A. Hoover and Robert A. Rushworth, 

“X- 15A-2 Advanced Capability,” paper presented at the annual symposium of The Society of 

Experimental Test Pilots, Beverly Hills, CA, 25-26 Sept. 1964. 

27. Love, X-15 flight chronology; cockpit voice transcription for Rushworth flight, 14 Aug 1964; 

X-15 Operations Flight Report, 19 Aug. 1964; Rushworth flight comments, n.d. 

28. Hoover and Rushworth, “X-15A-2 Advanced Capability”, NASA news release 66-1 1; C. M. 

Plattner, “Insulated X- 15A-2 Ready for Speed Tests,” Aviation Week W Space Technology (24 

July 1967), pp. 75-81. 

29. William J. Knight, “Increased Piloting Tasks and Performance of X- 15A-2 in Hypersonic 

Flight,” paper presented at the annual symposium of the SETP, Beverly Hills, CA, 28-30 Sept. 

1967; Love, X- 15 chronology. 

30. Johnny G. Armstrong, Flight Planning and Conduct of the X-15A Enuelqbe Expansion Program, 

AFFTC-TD-69-4; Love, X- 15 chronology. 

31. Becker, “The X-15 Program in Retrospect.” 

32. Interview with Jack Kolf, 28 Feb. 1977. 

33. Donald R. Bellman, et al., Investigation of the Crmh of the X-15-3 Aircraft on Nouentber 15, 1967 

34. Ibid.; passim; confidential interviews. 

35. X- 15 accident report, passim. 

36. Ibid.; R. Dale Reed, “RPRV’s: The First and Future Flights,” Astronautics W Aeronautics (Apr. 

1974), pp. 26-42. 

37. USAF Hq. Development Directive No. 32, 5 Mar. 1964, reprinted in X-15 System Package 

Program, 13-7. 

38. James E. Love and William R. Young, NASA TN D-3732, “Survey of Operation and Cost 

Experience of the X- 15 Airplane as a Reusable Space Vehicle” (Washington, DC: NASA, Nov. 

1966), p. 7; Bikle interview; Finch interview. 

39. J. C. Hunsaker and R C. Seamans, “Hugh Lather Dryden: 1898- 1965,” Biographical Memoirs oj 

the National Acadarry of Sciences (1969), p. 50. 

40. John V. Becker, “Principal Technology Contributions of X- 15 Program” (Hampton: NASA 

LaRC, 8 Oct. 1968), copy on file with the NASA History Office. 

369 

(Edwards: NASA FRC, Jan. 1968), pp. 8- 15. 
NOTES TO PAGES 128- 145 

41. Becker, “The X-15 in Retrospect.‘‘ 

CHAPTER 7 

1. NACA HSFS, Review of Aeronautical Research, HSFS (HSFS, n.d.) in the files of the office of the 

Deputy Director, DFRC. , c 

2. See, for example, the discussion of “ad hocracy” in Burt Nanus, “Profiles of the Future: The 

Future-Oriented Corporation,” Business Horizons (Feb. 1975), passim. Nanus’ essay could equally 

apply to FRC‘s history in the 1960s and 1970s. 

3. US. Congress, House Committee on Science and Astronautics, Authorizing Appr@riations to the 

National Aeronautics and Space Administration, Report No. 591 (Washington, DC: GPO, 1963), p. 

176. For a history of the committee, see Ken Hechler, Toward the Endless Frontier: Histov ofthe 

Commitee on Science and Technology, 1959-1979 (Washington, DC: GPO, 1980). 

4. U.S. Congress, Senate Committee on Aeronautical and Space Sciences, NASA Authorimtionfor FY 

1964, Report No. 385 (Washington, DC: GPO, 1963), p. 187. See also “Outlook Better for Flight 

Research Center,” Missiles and Rockets (8 Jul. 1963), p. 16. 

5. NASA FRC Five Year Plan Uul. 1963), in the files of the office of the Director, DFRC. 

6. See, for example, Loyd S. Swenson, Jr., James M. Grimwood, and Charles C. Alexander, This 

New Ocean: A History of Project Mercury, NASA SP-4201 (Washington, DC: NASA, 1966), p. 198. 

7. “X-20 Will Probe Piloted Lifting Re-entry,” Aviation Week W Space Technology (22 Jul. 1963), pp. 

230-240. 

8. Becker interview. The development of the X-20 in the context of lifting reentry research from 

1952- 1980 is examined in R. P. Hallion, “The Antecedents of the Space Shuttle,” AZAA Student 

Journal (Spring 1980), pp. 26-35. 

9. Hubert M. Drake, Donald R. Bellman, and Joseph A. Walker, NACA Research Memorandum 

RM H58D21, “Operational Problems of Manned Orbital Vehicles,” NACA HSFS, 12 Apr. 1958; 

Donald R. Bellman and Harold P. Washington, NASA Technical Memorandum TM X-636, 

“Preliminary Performance Analysis of Air Launching Manned Orbital Vehicles,” NASA FRC, 9 

Oct. 1961. 

10. Dana interview; Larry Grooms, “No Gold Watch for Old Faithful NASA Retiree,” Antelope 

Valley Ledger-Gazette, 28 Apr. 1970. 

11. D. S. Halacy, The Complete Book of Hang Gliding (New York: Hawthorn Books, 1975), pp. 24-27. 

12. James M. Grimwood, Barton C. Hacker, and Peter J. Vorzimmer, Project Gemini; Technology and 

Operations-A Chronology, NASA SP-4002 (Washington, DC: NASA, 1969), pp. 8, 17. 

13. FRC, Five Year Plan; Hubert M. Drake, “Aerodynamic Testing Using Special Aircraft,” (Edwards: 

NASA FRC, n.d.), pp. 8-9; NASA FRC X-Press, 26 Jan. 1968; interview of Richard Klein, 1 Mar. 

1977; interview of Joseph Wilson, 23 Feb. 1977; interview of Milton Thompson, 29 Mar. 1976. 

14. Klein interview. 

15. ibzd. Wilson interview. 

16. Thompson interview; see also Milton 0. Thompson, “I Fly Without Wings,” Air Progress (Dec. 

17. Klein interview; Wilson interview; FRC, Five-Year Plan; NASA X-Press, 26 Jan. 1968. 

18. Michael D. Keller, Langley chronology, pp. 84, 89; Bellman interview; FRC Five-Year Plan; 

NASA X-Press, 2 Mar. 1962; 1 Feb. 1963; 19 Feb. 1963. 

19. Oliver Stewart, Aviation: The Creative Ideas (New York: Praeger, 1966), pp. 144- 146; William 

Green and Roy Cross, The Jet Aircraft of the World (Garden City, N.Y.: Hanover House, 1957), p. 

172. 

20. Bellman interview; NASA X-Press, 1 Feb. 1963; Bell Aerosystems Company, Upruted LLRV 

Pre-Design Configuration Studies for Research and Training (July l964), p. 3. 

21. Francis J. OConnell, “Bell Unveils Lunar Training Craft,” Buffalo Courier Express, 9 Apr. 1964; 

“Lunar Landing Research Vehicle,” Space World, D-5-41 (May 1967), pp. 11-14; Bell, Uprated 

LLRV . . ., pp. 4-7; DFRC vehicle summary. 

22. NASA X-Press, 25 Sept. 1964; 6 Nov. 1964; 11 Dec. 1964; 19 Feb. 1965; 25 Mar. 1966; 1 Jul. 

1966; 26 Aug. 1966; 13 Jan. 1967; 27 Jan. 1967; Walker quote from Harold R. Williams, 

“Training for a Lunar Touchdown,” Rendezvous, VII, No. 1 (1968), pp. 5-7; “Lunar Landing 

Research Vehicle,” p. 11. 

1966), pp. IO-13,80-82. 

23. Ltr., Gilruth to Bikle, 28 Feb. 1967; NASA X-Press, 10 Mar. 1967. 

370 
b 

NOTES TO PAGES 145-159 

24. NASA MSC release 72-230; “Training for a Lunar Touchdown,” pp. 5-7; Zack Strickland, 

“Series of Lunar Landings Simulated,” Aviation Week &f Spwe Technology (30 June 1969), p. 55. 

25. “Training for a Lunar Touchdown,” p, 7. 

26. “Series of Lunar Landings Simulated,” p. 55. 

27. “Series of Lunar Landings Simulated,” p. 55; NASA MSC release 72-230; NASA MSC release 

68- 182. 

CHAPTER 8 

1. Reed interview; NASA X-Press, 10 Mar. 1967; Klein interview; Williams interview. 

2. Interview with Gus Briegleb, 18 May 1977; Reed interview; Klein interview; Bikle interview; 

3. Klein interview; NASA X-Press, 18 May 1968. 

4. M2-FI interflight worksheets, in DRFC pilot office files; Reed interview; Klein interview; 

“M-2 Research Craft Landed Seven Times,”Avietion Week (9 Sept. 1963), p. 34; Russell Hawkes, 

“M-2 Flight Successes Spur Interest in Lift Re-entry,” Missiles and Rockets (9 Sepr. 1963), pp. 

14-15; Thompson, ‘‘I Fly Without Wings,” pp. 12- 13; NASA X-Press, 10 Mar. 1967. 

NASA X-Press, 10 Mar. 1967. 

5. Letter, Bikle to Milton Ames, 24 Apr. 1963. 

6. U.S. Senate, Committee on Aeronautical and Space Sciences, Hearings: NASA Authorization fw 

Fiscal Year 1964, Pt. 1: Scientificand TechnicalProgram, 88th Congress, 1st Session, Apr. 1963, pp. 

40, 608-634; Pt. 2: Program Detail, 88th Congress, 1st session, June 1963, pp. 919-920. 

7. NASA news release 32-63; “Pilot Declares ‘Flying Bathtub‘ Makes Fine Re-Entry Vehicle,” The 

Oregonian, 6 Dec. 1963; Klein interview; DFRC monthly flight activities files for 1963 and 1964, 

DFRC pilot office files; interview with Jerauld Gentry, 11 Sept. 1975. 

8. Drake, “Aerodynamic Testing Using Special Aircraft,” pp. 8- 10; NASA FRC Five Year Plan. 

9. Ltr., Bisplinghoff to NASA center directors, 28 Oct. 1964. 

10. NASA news releases 64-41, 64-93, and NASA FRC release 14-64. 

11. Letter, Eggers to Bikle, 18 Aug. 1964; Bisplinghoff memo for NASA Associate Administrator, 

12. Northrop, “Lifting Bodies: Coming In on a Vanishing Wing,” p. 7; Bikle interview. 

13. AFFTC-FRC memo of understanding, 19 Apr. 1965, reprinted as Appendix V in FRC-AFFTC, 

Lifting Body Joint Operations Plan (Edwards: 1 Sept. 1969), pp. 8-9 to 8-9b. 

14. Addendum to memo of understanding, 11 Oct. 1966, reprinted as part of Appendix V in ibid., 

p. 8-9c. 

15. U.S. House, Committee on Science and Astronautics, 1967 NASA Authorization, Pt. 2, 89th 

Congress, 2nd session, Feb.-March 1966, pp. 1073-1077; ibid., 1968 NASA Authorimtion, Pt. 2, 

90th Congress, 1st session, Apr. 1967, pp. 101 1- 1012; “McDonnell Corp. Making Space Research 

Craft,” St. Louis Post-Disptach, 6 Jan. 1963; Frank G. McGuire, “First ASSET Launches Due in 

Summer,” Missiles and Rockets (14 Jan. 1963), p. 18; “Space Glider Lost at Sea After Suborbital 

Flight,” The Washington Post, 24 Feb. 1965; USAF AFSC news release 31.65; “START and SV-5 

Shuttle Gets Go-Ahead,” Space Daily, 4 Mar. 1965; “A Decision on AF Manned Space Shuttle 

Nears,” Space Daily, 20 Sept. 1965; William J. Normyle, “Manned Flight Tests to Seek LiftingBody Technology,” Aviation Week C9 Space Technology (16 May, 1966), pp. 64-75; “PRIME 

SV-5D-111 Maneuvers and Recovered,” Space Daily, 21 April 1967; James J. Haggerty. “USAF 

Finishes PRIME Project,” The Journal of the Armed Forces (3 June 1967), p. 9. 

16. Evert Clark, “Rocket Plane May Let Astronauts Land at Airfields,” The New York Times, 12 July 

1967; USAF AFSC news releases 85-66 and 59-67. 

17. NASA X-Press, 23 Apr. and 18 June 1965. 

18. NASA X-Press, 7 May 1965; NASA FRC news release 12-65; G. Warren Hall, “Research and 

Development History of USAF Stability T-33,”Journal ofthe American Aviation Historical Society 

(Winter 1974). 

19. NASAX-Press, 15 July 1966; chronology of lifting body flights prepared by Nancy Brun, NASA 

Historical Office; Gentry interview; NASA release 66-329; NASA X-Press, 5 May 1967. 

20. A comprehensive collection of official NASA accident reports and pilot interviews was published 

as “Pilot Work Load Cited in M2-F2 Crash,”Aviation Week W Space Technology (1 Oct. 1967); 

interview with Bruce Peterson, 26 Mar. 1976; interview with Wen Painter, 8 Aug. 1977; NASA 

X-Press, 19 May 1967. The accident eventually inspired both a popular novel and TV series. 

20 Aug. 1964. 

37 1 
* a 

NOTES TO PAGES 160- 177 

21. NASA FRC news release 10-68; NASA news release 69-15; NASA Ames Astrogram, 30 Jan. 

22. Brun chronology; M2-F3 progress and flight reports; OART M2-F3 Flash Reports. 

23. NASA X-Press, 14 and 28 Jan. 1966; “HL- 10 Delivered Today,” Space Daily, 18 Jan. 1966. 

24. Robert W. Rainey and Charles L. Ladson, “HL-10 Historical Review” (Hampton: LaRC, July 

25. Ibid. 

26. Brun chronology; HL- 10 progress and flight reports; OART HL- 10 flight reports. 

27. NASA FRC news release 8-70; NASA news release 70-71; Brun chronology; HL-10 flight 

reports. 

28. Memo, Bisplinghoff to NASA Associate Administrator, 30 June 1965; NASA Management 

Instruction 1052.96, “NASA-DoD (USAF) Memorandum of Understanding: Use of X-24A 

Research Vehicle in Joint Lifting Body Flight Research Program,” 7 Nov. 1967. 

1969. 

1969). 

29. Brun chronology; X-24A flash reports. 

30. Kolf interview. 

31. Everly Driscoll, “The Shape of Things to Come?” Science News (15 Sept. 1973), pp. 171- 172; 

Michael L. Yaffee, “X-24B Lifting Body Nearing Completion,” Aciation Week &3 Space Technology 

(4 Sept. 1972), pp. 77-79; John A. Manke and M. V. Love, “X-24B Flight Test Program,” 1975 

Report to the Aerospace Profession, The Society of Experimental Test Pilots, 26 Sept. 1975; 

Johnny G. Armstrong, Flight Planning and Conduct of the X-24B Research Aircraft Flight Test 

Program, AFFTC-TR-76-11 (Edwards AFB: AFFTC, 1977), pp. 12-14 (hereafter cited as Armstrong X-24B Report). 

32. Manke and Love, “X-24B Flight Test Program”; NASA Management Instruction 1052.968, 

“Provision for the Use of the X-24B Research Vehicle in a Jointly Sponsored NASA-DoD 

(USAF) Lifting Body Flight Research Program,” 4 Feb. 1972; Armstrong X-24B Report, pp. 

16-26; NASA news release 71-139; NASA FRC news release 30-71; notes of telecon, C. 

Karegeannes with Ralph Jackson, 13 Dec. 1972, in NASA History Office X-24B project files. 

33. NASA X-24B flight reports; Brun chronology; Manke and Love, “X-24B Flight Test Program”; 

Armstrong X-24B Report, pp. 89-97. 

34. Manke and Love, “X-24B Flight Test Program”; Brun chronology; interview with John Manke, 

1 Dec. 1976; Armstrong X-24B Report, pp. 78-82. 

35. Syvertson, “Aircraft Without Wings,” p. 50. 

36. NASA FRC, “Subscale Shuttle” (17 Aug. 1972); interview with Milton Thompson, 9 Aug. 1977; 

interview with Joe Weil, 18-Aug. 1977. 

37. Ibid. 

38. Donald P. Hearth and Albert E. Preyss, “Hypersonic Technology: Approach to an Expanded 

Program,” Astronautzcs &3 Aeronautics (Dec. 1976), pp. 20-37; “Hypersonic Aircraft by 2000 

Pushed and “USAF to Begin Hypersonic Testing” in Aviation Week &3 Space Technology (1 7 Sept. 

1973), pp. 52-57, 83-90; Marvin Miles, “Wingless Rocket Plane May Be Converted for Faster 

Test,” Los Angeles Times, 24 Dec. 1973; “Study Eyes Altering X-24 Lifting Vehicle,” Air Force 

Systems Command Newsreview, Jan. 1974; AFSC news release OIP 158.74; “Toward Hypersonics,” 

Flight (30 Oct. 1975), pp. 657-658; F. S. Kirkham, L. Robert Jackson, and John P. Weidner, 

“Study of a High-speed Research Airplane,” AIAA Journal ofAzrcrufi (Nov. 1975), pp. 857-863. 

39. “Hypersonic Propulsion Milestone Passed,” Aviation Week E3 Space Technology (9 May 1977), pp. 

49-5 1; Hearth and Preyss, “Hypersonic Technology”; Itr. of agreement between AFFTC, AFFDL, 

NASA LaRC, and NASA FRC, 15 Mar. 1977; AFFDL, “Technology Program Plan: NHFRF 

(AFSC, Jan. 1977), passim. 

40. Quoted in “NASA to End Manned Hypersonic Effort,” Aviation Week &f Space Technology (26 

Sept. 1977), p. 24; confidential sources. 

CHAPTER 9 

1. Library of Congress, Legislative Reference Service, Policy Planning for Aeronautical Research and 

Devel*tpment, US. Senate Committee on Aeronautical and Space Sciences, 16 May 1966, p. 9. 

2. OART, NASA Research and Technology Objectives: Aeronautics in the ’702, preliminary copy 

(Washington, DC: NASA OART, 16 Aug. 1971), p. 1. 

3’72 
NOTES TO PAGES 178-198 

3. OAST, OAST Research Centers, pp. 3-4 to 3-5,4- 1 to 4- 11. 

4. FRC, Five-Year Plan; Beeler interview; Thompson interview; Dana interview; DFRC vehicle 

5. FRC, Five-Year Plrm; Dana interview; NASA X-Press, 1 Feb. 1963, 25 Sept. 1964, 19 Nov. 1965. 

6. Betty J. Love, XB-70A flight log, in DFRC Pilots Office files; NASA X-Press, 12 Mar. 1965; 

interview with Donald Mallick, 10 Dec. 1976; Robert C. Seamans, Memo for Record; XB-70 

Flight Research Program Procurement, 16 Feb. 1967; XB-7OA #1 pilot report, flight 1-37,7 

Mar. 1966; Thomas G. Foxworth, “North American XB-70 Valkyrie,” Historical Aviation Akm, 

no. 7 & 8 (1969-1970), pp. 76-87, 164-175. 

7. Donald R. Bellman, “Briefing for NASA Headquarters on XB-F-104 Collision,” 7 Jul. 1966, 

hereafter referred to as XB-70A accident report. 

8. Ibid. 

9. Ibid. 

10. Ibid. 

11. Armistead interview. 

12. “Coast Air Collision Kills X-15 Test Pilot,” New YorR Times, 9 June 1966; see also XB-70A 

accident report. 

13. Love, in XB-70A chronology. 

14. Seamans memo for record, 16 Feb. 1967; Bikle and Manson, XB-70A working agreement, 22 

Mar. 1967, NASA news releases 67-59 and 67-75; NASA X-Press, 24 Mar. 1967 and 7 Apr. 

1967. 

summary. 

15. XB-70A chronology; Foxworth, pp. 168- 169. 

16. NASA X-Press, 7 Apr. 1967; memo, Donald T. Berry to Chief, FRC Research Division, 20 Jul. 

1967; XB-70A chronology. 

17. NASA X-Press, 17 May 1968 and 12 Jul. 1968; XB-70A chronology. 

18. NASA FRC news release 1-69. 

19. William T. Gunston, Bombers of the West (London: Ian Allen, 1973), p. 260. 

20. XB-70A chronology. 

21. FRC, “Proposal for NASA SST Flight Research Program,” n.d., passzm. 

22. George N. Chatham, Franklin P. Huddle, and the Science Policy Research Division of the 

Congressional Research Service, Library of Congress, The Supersonic Transport: A Look at the Key 

Issues (Washington, DC: American Industry and Labor for the SST, 1971), pp. 19-32. 

23. Clarence L. Johnson, “Some Development Aspects of the YF- 12A Interceptor Aircraft,” AIAA 

Journal of Aircraft (July-Aug. 1970), pp. 355-359; Richmond L. Miller, “Flight Testing the F- 12 

Series Aircraft,” AIAA Journal of Aircraft (Sept. 1975), pp. 695-698; Marcelle Size Knaack, 

Post-World War Two Fighters, u. I of Encyclopedia of US. Air Force Aircraft and Missile Systrms 

Washington, DC: USAF, 1978), pp. 333-334. 

Affairs Office, DFRC. 

24. Matranga interview; Klein interview; YF- 12 test program memoir, in the files of the External 

25. Ibid. (all). 

26. Ibid (all); also historical chronology of Edwards AFB, in the files of the History Office, AFFTC. 

27. YF-12 program memoir; interview with Victor Horton, 26 Feb. 1977. 

28. Matranga interview; Klein interview; Horton interview. 

29. YF- 12 program memoir. 

30. Ibid.; Horton interview. 

31. William S. Aiken, FRC YF- 12 Research Aircraft RTOP, 766-72-01,9 Mar. 1972, p. 2; see, for 

example, FRC Basic Research Reviews for NASA OAST Research Council, 20 Aug. 1974,20 Oct. 

1975, and Dec. 1976; hereafter cited as BRR. 

32. YF- 12A and YF- 12C flight chronology, DFRC YF- 12 project office files; information from 

Ray Young; Horton interview; Report of YF- 12 Ventral Incident Investigation Board, 25 Apr. 

1975; Klein interview. 

33. YF- 12 test program memoir; NASA X-Press, 3 June, 1977. 

34. NASA X-Press, 3 June 1977; Glenn B. Gilyard, “Supersonic Cruise Autopilot Operation,” BRR, 

20 Aug. 1974, pp. 23-24; Paul J. Reukauf, “Integrated PropulsionlFlight Control,” BRR, Dec. 

1976, pp. 23-25. 

35. DFRC YF-12 factsheet, n.d.; YF-12 test program memoir; BRR for 1974, 1975, and 1976. 

36. Conversation with Gene Matranga and Ming Tang, 10 Apr. 1978. 

373 
c a d 

NOTES TO PAGES 201 -215 

CHAPTER 10 

1. ’Krier interview; interview with Edwin Saltzman, 6 Dec. 1976; FRC Basic Research Reviews, passim; 

Fitzhugh L. Fulton, NASA TM X-56021, “Pilot’s Flight Evaluation of Concorde Airplane No. 

002 (FRC: Jan. 1974); Fitzhugh L. Fulton, “Flight Evaluation: Ford Tri-Motor, Model 4AT-B” 

(Nov. 1970); E. J. Saltzman and Robert R. Meyer, NASA TM X-56023, Mar. 1974. 

2. John D. Anderson, Jr., Introduction to Flight: Its Engineering and History (New York McGraw-Hill 

Book Company, 1978), pp. 171-172. 

3. Conversation with Thomas C. Kelly, 24 Apr. 1978; Memo, Toll to LaRC Assistant Director, 20 

Nov. 1968; L. K. Lotin, SCW meeting minutes, 21 Mar. 1967; Warren C. Wetmore, “New Design 

for Transonic Wing to be Tested on Modified F-8,” Aviation Week 6’ Space Technology, 17 Feb. 

1968, pp. 22-23. 

4. NASA History Office and the Science & Technology Division, Library of Congress, Astronautics 

and Aeronautics: 1970-Chronology on Science, Technology, and Policy (Washington: NASA, 

1972), p. 58. (This yearly chronology is subsequently cited as AA-year.) 

5. F-8 SCW flight log; AA-1970, pp. 359, 377-378; conversation with Thomas C. McMurtry, 20 

Apr. 1978. 

6. Interview with Thomas C. McMurtry, 3 Mar. 1977; McMurtry conversation. 

7. Ibid.; AA-1971, pp. 65-66; Kelly conversation; F-8SCW flight log. 

8. AA-1971, pp. 77, 94, 101, 114, 115, 141, 145, 163, 165, 233; F-8 SCW flight log. 

9. AA-1971, pp. 240-241,252,256,270-271, 279, 287, 346,349; AA-1972, pp. 72-73,94, 104, 

109,113,123,155,163,184,186,193,274-275,396;AA-1973, pp. 68-69,143; F-8SCW flight 

log; McMurtry interview and conversation. 

10. NASA FRC X-Press, 18 Feb. 1972; NASA FRC release 2-72; AA-1973, p. 143; AA-1974, pp. 44, 

112, 173. 

11. Air Force Systems Command release 188.71; NASA release 71- 124; interview with Wen Painter, 8 

Aug. 1977; interview with Einar K. Enevoldson, 4 Mar. 1977; General Dynamics TACT Management Plan and Program Manual, 11, FZP-1124-11, JuI 1970; General Dynamics, TACT Technical 

and Management Proposal, 11, FZP-1260 Revision A, 16 Aug. 1971; General Dynamics, TACT 

Manufacturing Plan, MFGP-595-00 1, 1 Dec. 197 1 ; General Dynamics, TACT Aircraft Geometric 

Characteristics, MAIR-595-19, 16 Apr. 1973; Air Force-NASA TACT Project Office, TACT Test 

Plan, Oct. 1973; Air Force Flight Dynamics Laboratory, TACT Data Analysis and Correlation Plan, 

Jul. 1975. 

12. 

13. 

14. 

15. 

16. 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

24. 

Painter interview; Enevoldson interview; Wen Painter, TACT Project Plan (NASA FRC, May 

1973); F- 11 1 TACT flight chronology, from the files of the TACT Program Office, DFRC. 

Enevoldson interview; F- 11 1 TACT flight chronology. 

Ibid.; NASA FRC, TACT: A Briefmg toIndust9 and Government (Edwards, FRC, Nov. 1975), passim. 

See Edgar Ulsamer, “On the Threshold of ‘Nonclassical’ Combat Flying,” Air Force Magazine 

(June 1977), pp. 54-58. 

R. Dale Reed, “RPRV’s: The First and Future Flights,” Astronautics @Aeronautics (Apr. 1974), pp. 

Ibid. R. Dale Reed, “Can the RC‘er Contribute to Aeronautical Research?” Radio Control Modeler 

(act. 1968), pp. 28-35; C. M. Plattner, “Lifting Shape for Hypersonic Maneuvers,” Aviation 

Week 6’ Space Technology (29 Sept. 1969), pp. 54-58; R. Dale Reed, “Flight Demonstration of a 

Remote Piloted Concept Utilizing the Unmanned Hyper 111 Research Vehicle,” paper presented 

at the 26th meeting, Society of Automotive Engineers’ Aerospace Vehicle Flight Control Systems 

Committee, Seattle, 23-25 Sept. 1970. 

Reed, “Flight Demonstration of a Remote Piloted Concept Utilizing the Unmanned Hyper I11 

Research Vehicle.” 

Reed, “RPRV’s: The First and Future Flights,” pp. 32-33; NASA FRC news release 16-72. 

Reed, “RPRV’s: The First and Future Flights,” pp. 33-37; NASA OAST, “FRC Project Management Report: 3/8 F- 15 Remotely Piloted Research Vehicle,” internal management document, 

15 Jan. 1973. 

Ibid.; Layton interview. 

Quoted in Reed, “RPRV’s: The First and Future Flights,” p. 39. 

Layton interview. 

Manke interview; Dana interview. 

26-42. 

374 
I iy 16 1 * 

NOTES TO PAGES 216-238 

25. Interview with Jennifer Baer, 8 Aug. 1977; Reed interview; Reed, “RPRV’s: The First and 

Future Flights,” pp. 39-42; NASA FRC X-Press, 15 Jul. 1977; DFRC information sheet on the 

“Firebee 11,” n.d.; Rockwell International, “HiMAT Preliminary Design Review Oral Briefing,” 

11 May 1976; Jeffrey M. Lenorovitz, “Tooling Begins for Research Vehicles,” Aviation Week €3 

Space Technology (21 Feb. 1977), pp. 36-39. 

26. Jerry Noel Hoblit, “F- 105 Thunderchief,” in Robin Higham and Abigail T. Siddall, eds., Elying 

Combat Aircraft of the USAAF-YSAF (Ames, Iowa: Iowa State University Press, 1975), p. 88. 

27. Krier interview; NASA FRC news release 8-72; J. P. Sutherland, “Fly-by-Wire Control Systems,” 

Air Force Flight Dynamics Laboratory, 10 Aug. 1967. 

28. In AA-1973, pp. 74-75. 

29. I&., pp. 196, 266; Krier interview; info from Kenneth J. Szalai. 

30. Quote from confidential source; for information on the IPCS system, see Jennifer L. Baer, Jon 

K. Holzman, and Frank W. Burcham, Jr., “Procedures Use din Flight Tests of an Integrated 

Propulsion Control System on an F-IIIE Airplane,” paper presented to the Aerospace Engineering and Manufacturing Meeting, Society of Automotive Engineers, San Diego, 29 N0v.-2 Dec. 

1976 (hereafter referred to as “IPCS Procedures”); interviews with Wen Painter, Gary Krier, and 

Einar Enevoldson; planned IPCS schedule as prepared by the Research and Engineering Division, 

The Boeing Company; NASA FRC IPCS Milestone Schedule, 11 Mar. 1976. 

3 1. IPCS Procedures; Painter interview; Enevoldson interview. 

32. IPCS Procedures. 

33. NASA DFRC, “X-Press,” 2 June 1978, and 16 June 1978. 

34. Theodore von KArmAn, Aerodynamics: Selected Topics in Light of Their Historical Development (Ithaca, 

35. Philip J. Klass, “Wake Vortex Sensing Efforts Advance,” Aviation Week U Space Technology (25 

36. Ibid. 

37. David Scott, “Today’s Research-Tomorrow’s Aircraft,” Pt. 2, Aircraft (Aug. 1974), pp. 30-32. 

38. Ltr., Robert F. Thompson to FRC Deputy Director, 16 Aug. 1974; “NASA’s 747 Shuttle Carrier 

39. Klass, “Wake Vortex Sensing Efforts Advance,” p. 99. 

40. NASA FRC X-Press, 29 Jul. 1977. 

41. Memo, J. M. Groen to FRC director, 17 Jan. 1972. 

42. See memo, J. M. Groen to De E. Beeler, 3 June, 1971; memo, Groen to FRC director, 17 Jan. 

43. Bikle interview. 

44. Confidential source. 

45. For F- 11 1 information, see the following issues of the NASA FRC X-Press: 27 Jan, 1967; 19 

Apr. 1968; Apr. 1969; and v. 14 no. 7 (n.d.). 

46. Harold Walker, “High-Performance Aircraft Research,” DFRC, n.d.: “ ‘Short’ Program Summary,” 

n.d., transmitted to the author by Milton 0. Thompson; Thomas R. Sisk, “Transonic Lift 

Augmentation Devices,” Bask Research Review (Aug. 197 1); NASA, Flight Research Center (Edwards: 

FRC, 1971), pp. 19, 31. 

NY: Cornell University Press, 1954), pp. 48-50. 

Apr. 1977), pp. 92-99. 

Aircraft Not New to Heavyweight Ranks,” Boeing news release A-0919 (n.d.). 

1972; ltr., James S. Martin to Milton 0. Thompson, 4 Jan. 1971. 

47. Kolf interview; NASA DFRC X-Press, 2 June 1978. 

48. Krier interview. 

49. Confidential source. 

50. Memo, Thompson to Scott, 2 Jan. 1976. 

5 1. OART, NASA Research and Technology Objectives, p. 1 

CHAPTER 11 

1. Personal observations. 

2. Richard L. Chapman, Robert H. Pontious, and Lewis B. Barnes, Project Management in NASA: The 

System and the Men (National Academy of Public Administration Foundation, Jan. 1973), p. 6. 

3. Data from Scherer biographical files, DFRC and NASA History Office; Finch interview. 

4. This represents a consensus of statements from numerous interviews with DFRC personnel. 

375 
NOTES TO PAGES 238-254 

5. Personal observations and consensus of interview statements; NASA DFRC X-Press, 16 June 

1978. 

6. E. P. Smith, “Space Shuttle in Perspective: History in the Making,” pp. 8- 11; NASA release 

77- 16, “Space Shuttle Orbiter Test Flight Series,’’ pp. 57-58; NASA DFRC X-Press, 24 Feb. 

1978. 

7. Ltr. and attachment, Robert F. Thompson to Myron S. Malkin, 16 Oct. 1974; ltr., Kraft to 

Scherer, 23 Oct. 1974. 

8. Personal recollections. 

9. Captive inert flight-test postflight reports, reports of DFRC Shuttle news conference, 18 Feb. 

1977; personal recollection. 

10. Donald E. Fink, “Orbiter Flight Plan Expanded,” Aviation Week W Space Te&ndogy, 27 June 1977, 

pp. 12-14; NASA release 77-16, passim. 

11. Ibid.; Jeffrey M. Lenorovitz, “Shuttle Orbiter Test Phase Trimmed,” Adion Week .E3 Space 

Technology, 4 Jul. 1977, pp. 18- 19. Captive active flight-test postflight reports. 

12. Free flight test postflight reports; Donald E. Fink, “Orbiter Responsive in Free Flight,” Aviation 

Week W Space Technology, 22 Aug. 1977, pp. 12-19; George Alexander, “Space Shuttle Sails 

Through Solo Flight,” Los Angeles Times, 13 Aug. 1977; Alan Brown, “Fantastic!” Antelope 

Valley Ledger-Gazette, 12 Aug. 1977; Antelope Valley Ledger-Gazette, 15 Aug 1977; much of this 

on-site material is from personal recollection. 

13. Free-flight test postflight reports. 

14. Ibid.; personal recollection. 

15. Free-flight test postflight reports. 

16. Ibid.; Donald E. Fink, “Orbiter Experiences Control Problems,” Aviation Week C3 Space Technology, 

17. NASA DFRC X-Press, 24 Mar. 1978; “Space Shuttle Contributions Recognized,” NASA Achvities 

(Apr. 1978), pp. 25-27; “Shuttle Orbiter Ferried to Huntsville,” Avietion Week U Space 

Technology, 20 Mar. 1978, p.15. 

18. NASA DFRC X-Press, 11 Jan. 1980 and 1 May 1981; DFRC news release 81-19, 81-24. 

19. NASA DFRC X-Press, 1 May 1981. 

20. NASA DFRC X-Press, 7 Aug. 1981. 

21. Letter, Lee R. Scherer to George Low, 19 June 1973, DFRC Director’s files. 

22. Ibid. 

23. Ibid. 

31 Oct. 1977, pp. 16-17. 

376 
Index 

A3D (Skywarrior; attack bomber), 60 

A4D(Skyhawk; attack bomber), 60 

A-5A (Vigilante; strike aircraft), 174 ill., 180, 

A-9A (experimental attack bomber), 228 

AD (Skyraider; attack bomber), 60 

AD-I (NASA research aircraft), 250, 251 ill., 

Abbott, Ira H., 104 

Ablator (coating), 120-22 

Adams, Michael J., 123-24, 125n, 336,337,360 

Advanced Fighter Technology Integration program (AFTI), 208-09 

Aero-Commander, 223 ill. 

Aerodynamic heating, 75, 114-15, 120, 121-22 

Aeronautical research. See Air Force, US.; 

Ames Research Center; Budget, NASA; 

Dryden Flight Research Center; Flight 

Research Center; High Speed Flight Station; Langley Research Center. 

Aerospace industry, xi, 62,89, 178,232-33. See 

alsu Contractor relations. 

AerothermodynamidElastic Structured Systems 

Environmental Tests (ASSET), 155, 170 

Aiken, William S., 9 

Air Force Flight Dynamics Laboratory, 165-66, 

Air Force Flight Propulsion Laboratory, 220 

Air Force Flight Test Center (AFFTC), xi, 41, 

72, 78, 104, 118, 152, 155, 164, 166, 170, 

185,227 

Air Force, U.S., xvii, 63-64,98, 104, 125, 136. 

148, 216, 231. See alsu Edwards AFB. 

flight testing, 37, 47, 65, 67, 69-74, 75, 76, 

78, 181 

hypersonic research, 108, 109, 1 10-1 1, 170 

and NACA, 23-27,31, 33,48,55,56,57, 87, 

and NASA, 118-19, 120, 124, 154-57, 160, 

283 

256,280 

170, 206, 207, 208-09 

88, 89, 90-91, 92, 96-97 

163-64, 165-66, 182, 184, 185, 190-94, 

207-09, 2 12- 13, 220, 227, 229, 230, 240, 

255,256 

Air Materiel Command (AAF), 13, 25, 319 

Air Research and Development Command, 91, 

Algranti, Joseph S., 144, 145, 146 

Allen, H. Julian, 14, 147 

97 

Ames, Milton B., 151 

Ames Research Center (ARC), 14,26,29,273, 

277 

aeronautical research, 31,56,57,89,95, 177, 

178, 181, 190; 191, 193, 194, 225-26 

and Dryden FRC, 207,208,215, 252-58 

hypersonic research, 102, 108 

liftingbody research, 147, 148, 149, 150,153, 

157-58, 161, 164 

Anderson, John, 201 

Andrews, Bill, 248 

Antelope Valley, Mojave Desert (“Aerospace 

Valley”), xi 

Apollo-Saturn program, 118, 119, 131, 140-41 

Apt, Milburn G. (Mel), 76-78, 251, 316 

Armstrong, Johnny G., 166 

Armstrong, Neil A., 52n, 94, 136, 138, 140, 

Army Air Forces (AAF), xv, 6, 7,9, I 1, 12, 13, 

Army, U.S., xvii, 6, 26 

Arnold, Henry H. (Hap), xv, xvii 

Astronauts, 146-47 

Atmospheric studies, 226-27 

Atomic Energy Commission (AEC), 59-60 

B-1 (experimental bomber), 233 

B-17 (Flying Fortress; bomber), xviii 

B-29, B-29A (Superfortress, bomber), 16, 17, 

8-45 (Tornado; bomber), 30n 

B-47, B-47A (Str-atojet; bomber), 35, 88-89, 

B-50 (Superfortress; launch vehicle), 66 ill. 

B-52 (Stratofortress; bomber), 89, 2 15 ill., 253 

B-57B (Night intruder; bomber), 226, 227 

B-58 (Hustler; bomber), 57, 179 

Baker, Joel, 9 

Baker, Robert, 10 ill. 

Barber, Russ, 226 

Barnes, Florence (“Pancho”), xv 

Barnett, Larry, 351 

Becker, John V., 33,34, 106, 108-09, 116, 122, 

Beeler, DeElroy E., 13, 15, 16, 17 ill., 44,45 ill., 

145-46, 218, 294, 326, 330, 331, 332 

34 

47, 62, 84 ill., 283 

283 

ill. 

126-28 

46, 72, 104-05, 134, 149, 170, 237 

377 
ON THE FRONTIER 

Beggs, James M., 252 

Bell, Larry, 19 

Bell Aerosystems Go., xvii, 6, 11, 12,13, 19,31, 

63, 70, 71-72, 74, 75, 76, 107, 109, 140, 

141, 142, 145,285,315,323 

Bellis, Benjamin, 213 

Bellman, Donald R., 69, 73, 80, 124, 142, 184 

Bikle, Paul F., 105 ill., 138-39, 236, 261 

and Air Force, 155, 164, 185 

managementpolicy,45,104-06,134,140,227 

Bisplinghoff, Raymond L., 134, 152, 154, 163 

Blackbird program. See Supersonic flight reBlunt body theory, 147-48 

Boeing Co., 89, 136, 188, 189, 220 

Boeing 727 (airliner), 225 

Boeing 747 (airliner), 224,225 ill., 239-41,242 

ill., 243, 244, 245-46, 247-48, 250, 280 

Boost-glider, 47, 101, 106-07 

Boyd, Albert, 13, 26 iIl., 27, 91, 287, 310, 319 

Boyd, Jack, 252 

Boyd, Stan, 221 

Boyd, Stu, 208, 22111 

Branch, Irving, 155, 164 

Bredt, Irene, 106-07 

Bridgeman, William B., 57, 65, 305-06, 310 

Briegleb, Gus, 149 

Brown, Beverly P., 9 

Buckley, Edmond C., 24,46 

Budget, NACA, xix, 31, 32, 43 

Budget, NASA, 101 

M-2, M-2-F1, 149, 151, 152, 154 

X-15, 117, 118, 125 

search, YF-12. 

and DFRC, 105, 171, 180, 181-82, 191, 193- 

marine$ spaceflight, 132-34, 169-70, 177 

Burke, Melvin, 218 

Butchart, Stanley P., 52n, 72,89,303,312,320, 

94, 198, 227, 253-54, 275-77 

321, 324, 325-26 

C-47 (M2-Fl and Parasev tow aircraft), 151 

Caldwell, Turner F., Jr., 299 

Campbell, W., 349 

Cannon, Joseph, 66, 292 

Carl, Marion, 67, 307, 312 

Carman, L. Robert, 107 

Carroll, Franklin O., 7 

Carter, Ryland, 29 

Central airborne performance analyzer 

Century series. See F-100, F-101, F-102, F-104, 

Cernan, Eugene A., 145 

Champine, Robert A., 21, 30,36-37,52n, 290, 

Chanute, Octave Award, 128 

Charles, Prince of Wales, 249 

Chidlaw, Benjamin W., xvii 

Childs, Stuart R., 293 

(CAPA), 197 

F-105, and F-107. 

300, 301,304, 305 

Civil Aeronautics Administration (CAA), 89, 

Civilian aircraft. See Aerospace industry. 

Clousing, Larry, 29 

Collier, Robert J., Trophy, 19, 128 

Columbia (Space Shuttle orbiter), xix, 3, 121, 

Computer, 75-76,92, 110, 192, 193, 197, 218, 

219,221 

Concorde (Anglo-French supersonic transport), 

189, 217 

Configuration, aircraft, 60-6 1, 6 1-62, 2 17- 18, 

233. See also Supercritical wing and Wing 

design. 

222 

122,250-51 

bomb and tank shapes, 59-60 

delta wing, 48, 50, 55, 56 ill., 57 

low-aspect-ratio thin wing, 48, 57 

semitailless, 48, 54 

sweptwing, 47, 48, 50-51, 89, 216 

variable-sweep, 48, 52, 53 ill., 54 

Congress, US., 31, 33, 43, 98n, 132, 134, 151, 

177, 189. See also House and Senate committees. 

Contractor relations 

NACA, 38,46-47,60, 75, 87, 88,89,92,94, 

NASA, 98, 109-1 10,154, 170,193,204,206- 

07, 213, 216, 220, 229, 232-33, 238-39 

107 

Convair, 327 

Cook, Orville R., 90 

Cook, Rex, 72n 

Cooper, George, 32 1 

Cornel1 Aeronautical Laboratory, 158, 180 

Cornell-Guggenheim Aviation Safety Center, 

Corum family, xv 

Cosenza, Charles J.. 208 

Cotton, Joe, 182, 183, 184, 185, 187, 347, 348 

Craigie, Laurence C., 90 

Crippen, Robert L., 251, 252 

Cross, Carl. 182, 183, 184 

Crossfield, A. Scott, 45 ill., 52n, 67, 68 ill., 69, 

72, 84 ill., 92, 96. 97. 112, 114, 251, 291, 

223 

301-02, 303, 304, 306, 309, 310, 311-13, 

319-20, 321, 323, 324, 325, 327, 329, 330 

Crowley, Gus, 12, 13, 25, 31, 32, 78, 108 

Curtis, Billy A., 192 

D-558- 1 (Skystreak; research aircraft), 6, 20, 

27, 28 ill., 29, 34, 35 ill., 39, 49 ill., 279, 

D-558-2 (Skyrocket; research aircraft), 36 ill., 

39, 49 ill., 51 ill., 52, 63, 64, 65, 66-67, 

68 ill., 69, 84 ill., 279, 299-314 

299-314, 360 

configuration, 48, 60 

pitch-up problem, 36-37, 47, 48, 50, 51 

Dana, Bill, 125, 152, 158, 160, 162, 168, 180, 

257 ill., 335,336, 337,340, 341, 342,343, 

344, 352, 353 

378 
F 

Dassault, Marcel, 57 

DAST, 281 

Day, Richard, 76 

Defense, Dept. of, 151, 181, 231 

De France, Smith J., 14, 38 

de Havilland, Geoffrey, 11-12 

De Havilland D.H. 108 (Swallow; British research aircraft), 12, 37 

Delta-wing aircraft. See Configuration, aircraft. 

DeMeritte, Fred J., 166 

De More, Richard, 72 

Diehl, Walter, 6, 14 

Digital Electronic Engine Controls (DEEC) reDigital fly-by-wire (DFBW), 2 18-20 

Distinguished Service Medal, NASA, 128 

Dives, W.E., 124 

Doolittle, James H., 244 

Dornberger, Walter R., 107 

Douglas Aircraft Co., 27, 34, 60, 64, 65, 109- 

Drake, Hubert M., 76, 80, 82, 107, 119, 141 

Dryden Flight Research Center (DFRC), xi, 

xviii-xix, 44, 103, 168, 235-38, 253 ill., 

See also Flight Research Center, High Speed 

Flight Station and Muroc Flight Test Unit. 

aeronautical research, 3,6, 172,215-16,251, 

military aircraft, 171, 222, 230-33, 250-51 

Space Shuttle, 172, 219-220,238-50, 357 

and NACA, 14,25,29,31,32,85, 107, 109 

and NASA, xix, 103, 235, 258 

and research aircraft, 19, 64, 68, 126, 152 

Dryden, Mrs. Hugh L., 235, 236 ill. 

Dyna-Soar (X-20A; research aircraft), 47-48, 

search program, 222 

10, 299 

256-58,269,270,271, 273, 275, 276, 277. 

254-56, 359-60 

Dryden, Hugh L., 45 ill. 

106, 107, 117, 122, 136-37, 152 

Edwards Air Force Base, Calif., xi, xvii, 70 ill., 

72. See also Muroc AFB. 

and NACA, 41-44,46,47, 73 

and NASA, 102 

Space Shuttle, 240, 250, 251 

Edwards, George, 147, 148 

Edwards, Glen W., xvii, 41 

Eggers, Alfred J., Jr., 147-48, 154 

Eldredge, Dick, 149 

Electronic controls, 2 16-22 

Enevoldson, Einar, 168,208,212,214,257 ill., 

Engines, aircraft, 17,27,29,3 1,49,57,61,62, 

345,353 

63, 64, 74, 75, 80-81, 97, 119, 190, 193, 

229,299,304 

585-21, 215 

TF30-P-9, 22 1 

XLR-11, 9, 110, 154, 157, 158, 160, 161, 

XLR-99, 112, 114, 116, 117, 169, 170 

162, 164, 166, 167, 168 

INDEX 

Engle, Joe H., 242, 247, 333, 358 

Enterprise (OV-101; Space Shuttle orbiter), xix, 

7, 165, 239-241, 242 ill., 243-45, 246 ill., 

247, 248 ill., 249-50, 253 ill. 

Everest, Frank (“Pete”), 65,71,75,76,91,287- 

88,295,308,313, 315,316,319 

Exceptional Service Medal, NASA, 128, 250 

Experimental Aircraft Association, 149 

FAA, F-4B (Phantom 11; fighter-bomber), 182, 

F-5A (Freedom Fighter), 182, 183, 229-230 

F5D-1 (Skylancer; experimental fighter), 136, 

137 ill., 179, 282-83 

F-8, F-8A, F-8C (Crusader; fighter), xix, 178, 

203-04, 205, 206 ill., 2 17- 18, 2 19 ill., 228, 

256,280 

F-14, F-14A (Tomcat; fighter), 217, 233, 251, 

283 

F-15, F-15A (Eagle; fighter), 198, 213, 214, 

231 ill., 283 

F-15 (NASA remotely piloted research vehicle; 

RPRV), 213-214, 215 ill., 281 

F-16, F-16A (Fighting Falcon; fighter), 219, 

230,231, 232 

F-18 (Hornet; fighter), 230, 232 

F-86, F-86A, F-86F, (Sabre; fighter), 36, 70 ill., 

80, 84 ill., 230, 232, 281 

F-89 (Scorpion; interceptor), 88 

F-100, F-100A, F-IOOC, (Super Sabre; fighter), 

21, 51, 61, 77, 89, 90, 91, 92, 93 ill., 96, 

97, 175 ill., 281, 360 

F-101, F-IOlA, (Voodoo; fighter), 51, 61, 90, 

282 

F- 102, F- 102A, (Delta Dagger; interceptor), 56- 

F-104, F-l04A, F-l04B, (Starfighter; interceptor), 57, 80, 90, 91, 94, 95 ill., 96, 97, 

114 ill., 136, 180, 217, 229, 282, 360. 

F-104N (NASA research aircraft), 182434,227, 

228 ill., 282, 360 

F- 105, F-l05B, (Thunderchief; fighter-bomber), 

96,2 16,282 

F-106 (Delta Dart; interceptor), 57 

F- 107 (experimental fighter-bomber), 90, 95- 

183, 227-28, 282 

57, 90-9 I, 282 

96, 112,360 

11 1 A, (Aardvaark; strike aircraft), 178, 

207,208,209 ill., 220, 221,222,228,229, 

230 ill., 256, 282 

FDL-8 (reentry shape), 170 

FA1 Gold Air Medal, 128 

Federal Aviation Administration (FAA), 139, 

Finch, Thomas, 94 

Fitzgerald, James T., Jr., 286, 287 

Flax, Alexander, 163-64 

Fleming, Patrick, 288 

Fletcher, .James C., 207, 235 

F-111, F-IlIA, F-lIlD, F-IllE, F-lllF, FB178, 188, 189, 194,222,224 

379 
E I 

ON THE FRONTIER 

Flight Achievement Award, 128 

Flight control systems, 178. See also Integrated 

Propulsion Control System. 

Flight Research Center (NASA), xix, 42, 103, 

277, 347, 359-60. See also Dryden Flight 

Research Center, High Speed Flight Station, and Muroc Flight Test Unit 

aeronautical research, 134-35, 172, 177-78, 

104-05, 265, 266, 267, 268, 273, 275-76, 

201-02,210,211,212,213-14,217-19,223, 

224, 225-30 

164-68, 169-72 

137-40, 141-46 

lifting body resexch, 137, 148-51, 152-63, 

manned spaceflight, 102, 131-34, 135-36, 

SST, 137, 178-80, 181-82, 184-87, 196-97 

X-15 program, 98, 116-17, 118, 124-26, 129, 

YF-12 proqram, 189-96, 197 

227 

Flight Satety Foundation, 223 

Flight testing. See Budget, NACA and individual 

Flying bedstead. See Vertical-takeoff-and-landing 

Forsyth, Charles M., 9 

Frazier, W., 356 

Fritz, John, 182 

Frosch, Robert, 244 

Frost, Dick, 11, 13, 15-16 

Fullerton, Gordon, 242, 243, 247, 358 

Fulton, Fitzhugh L., 185, 187, 192, 193, 243, 

244, 248, 249, 250, 257 ill., 347, 348, 349, 

350,351, 352, 353,354, 355, 356 

aircraft names. 

aircraft (VTOL). 

Gardner, John J., 9 

Gates Leatjet (NASA research and mission supGemini program, 131. 137. 138. 140 

Gentry, Jerauld, 154, 158-59, 160, 162, 164, 

Gerdes, Ron, 206 

Gilkey, Signa, 25 

Gillam, Isaac, 106, 238, 239 ill., 252, 258, 261 

Gilruth, Robert R., 137, 145, 169 

Glamorous Glenn&. See X- 1. 

Glennan, T. Keith, 235 

Goddard Space Flight Center (GSFC), 252 

Goodlin, Chalmers, 11, 12, 285, 286, 288, 289 

Goodman, Hal, 16 

Gough, Mel, 7, 14 

Griffith, A. A., 142 

Griffith, John, 21, 37, 52n, 59, 290-91, 301, 

Grissom, Virgil I., 140 

Group Achievement Award, NASA, 128 

Grumman Aircraft Co., 87, 140-41, 217, 251 

Guidry, Skip, 241 

HL-10 (lifting body research aircraft), 164, 165 

380 

port aircraft), 225 ill. 

339,340, 341, 342 

304-05, 3 19 

174 ill. 

flight testing, 153,154,157,159,160,161-63, 

339,340,341,342 

and Space Shuttle, 163 

Haise, Fred W., 158, 223, 242, 243, 244, 245- 

Hakes, Ralph, 154 

Haley Astronautics Award, 128 

Hanes, Horace B., 293 

Hansen, Grant, 212 

Harer, Richard B., 293 

Harmon Trophy, 128 

Harper, Robert, 158 

Hayes, Norman, 10 ill. 

Hedgepeth, John, 101 

Heidlebaugh, G., 349 

Hello, Buz, 157 

High Altitude Continuous Tracking Radar 

Range (High Range), 110-1 1 

High-speed Flight Station (NACA HSFS), xviii, 

33, 43 ill., 44 ill., 45 ill., 46, 98, 222, 264, 

275, 276, 359-60. See also Dryden Flight 

Research Center, Flight Research Center, 

and Muroc Flight Test Unit. 

hypersonic research, 101-02, 107-08, 110-12 

lifting body research, 148, 149 

military research, 46-48, 59-60, 87, 88, 89, 

X series research, 55, 57, 58, 62, 67-68, 71- 

46,247,249 

91, 92, 94-96, 97-98 

74, 76, 78, 79, 80, 85, 315, 319, 323 

High Speed Research Aircraft (HSRA), 170 

HiMat (Highly Maneuverable Aircraft Technology; RPRV), 215-16, 251, 256, 281 

Hinman, Howard, 9 

Hoag, Peter C., 162, 163, 182, 183, 184, 340, 

Holloman, George V., xvi 

Holtoner, J. Stanley, 12, 294 

Honeywell Co., 122, 220 

Hoover, Herbert H., 13,20,21,29,30,289,290 

Hoover, Robert, 13, 15-16 

Horner, Richard E., 154 

Horton, Victor, 124, 138, 149, 151, 152, 241, 

349,350,351,352,353,354,355, 356 

Householder, John B., 10 ill. 

House of Representatives. Committee on 

Huesaker, Jerome, 25-26, 32, 45 ill., 126 

Hyper 111 (lifting reentry configuration; 

RPRV), 210-1 1, 212 ill,, 281 

Hypersonic aircraft, 101-03, 107, 108 ill., 109, 

235. See also Ablator, Configuration, aircraft, and X-15. 

Hypersonic Ramjet Experiment (HRE), 109, 

Hypersonic Research Facilities study (HYFAC), 

Incremental Growth Vehicle, 170 

341,342 

Science & Astronautics, 134 

1 19-22 

170, 171 
0 d r * a 

Inertial coupling research (roll coupling; roll 

divergence), 58-59, 76-77,92, 93,94, 101 

Integrated Propulsion Control System (IPCS), 

220,22 1 I 222 

Ishmael, Stephen, 353 

585-2 1. See Engines, aircraft. 

JF- l00C (NASA research aircraft), 281 

JTB-29A (USAF-NACA rocket airplane launch 

Jackson, Ralph, 240 

.Jet aircraft, xvi-xvii, 2 I, fil,89, 177-78,224,225 

Jet Propulsion Laboratory (JPL), 2 16 

Jetstar (GPAS; NASA research airplane), 180, 

Jewett, C;., 356 

Johnson, Clarence (“Kelly”), 80, 189-90 

Johnson, Lyndon B., 184, 189, 190 

Johnson, Richard L., 288, 319 

.Johnson Space Center USC), 172, 225, 240, 

Johnston, Alvin M., 289 

Joint Parachute Test Facility, 227n 

Jones, Robert T., 2 15, 250 

Jones, Walter P., 52n, 302,3 10,3 1 1,320,323-24 

Josephs, Lyman, 157 

KC-I 35 (Stratotanker; air refueling aircraft), 

Kelly, Thomas C., 204, 205 

Kennedy, John F., 189 

Kent, Marion, 31, 43 ill., 45 ill. 

Kenyon, George, 147, 148 

Kincheloe, Iven, 76, 77, 79, 97, 316 

Kinchelow, Iven, Award, 128 

Klein, Richard, 138, 139 

Kleuver, End, 140, 144, 145 

aircraft), 283 

186, 244 ill., 280 

241, 242, 246,256, 357 

88, 89,222, 224, 25 I, 283, 35 1 

Knight, William J. (“Pete”), 118, 120, 121-22, 

Kolf, Jack, 122, 166 

Kotcher, Ezra, 6, 34 

Korean war, 41 

Kramer, James J., 171 

Krier, Gary, 204, 205, 218, 221, 393 

L-39 (NACA research aircraft), 30, 36 

L-1011 (TriStar; jet transport), 224, 236 

Lanchester, F. W., 223 

Langley Lunar Landing Research Facility, 141, 

Langley Memorial Aeronautical Laboratory. 

Langley Research Center (LaRC), 72, 119, 170, 

aeronautical research, 31,52,57,79,89, 177, 

lifting body research, 148, 153, 161 

manned spaceflight, 102, 138, 141 

military aircraft, 107-08, 118 

125, 251, 335,336 

145 

See Langley Research Center. 

171,219, 223, 254-55, 256, 277 

203,204,205,208,212-13,224-25,226-27 

INDEX 

and Muroc FTU, xviii, 6, 7, 9, 13-14, 26, 

YF-12 program, 191, 192, 194-95, 197 

29-30, 33,42, 44 

Layton, Gary, 139 

Layton, Ronald J., 192, 350 

Levin, Kenneth L., 142 

Lewis Research Center (LeRC), 14, 31,61,97, 

Lifting body research, 147-72, 339-46 

Lilly, Howard C., 13, 21, 27, 28 ill., 29-30, 34, 

Liquid rocket propellant, 6, 16, 18, 119 

Littleton, Charles, 72 

Lockheed Co., xi, 94, i90, 193 

Loftin, Lawrence K., 204 

Love, Betty, 126 

Love, Eugene, 161, 163 

Love, Michael V., 167-68, 344 

Lovelace, Alan, 252 

Low-aspect-ratio thin wing aircraft. See ConLunar Excursion Module. See Lunar Module. 

Lunar Landing Research Vehicle (LLRV), 137, 

Lunar Landing Training Vehicle (LLTV), 

Lunar Module, 14111, 218 

Lundquist, Gustav E., 287 

M-2 (lifting body design), 148-49, 153, 280, 

M2-FI (lifting body), 149-52, 153, 157, 173 ill., 

M2-F2 (liftingbody), 152, 154, 157, 158-61, 174 

M2-F3 (lifting body), 160, 161, 174 ill., 280, 

McAvoy, Bill, 87 

McDonnell Aircraft Co., 2 13, 2 14, 239 

McDonnell Douglas Gorp., 155 

Mach, Ernst, 4n 

McKay, John B., 52n, 72, 79.94, 1 17-18,294, 

108, 178, 191, 220, 221, 254-55,256,277 

289,290, 300,360 

figuration, aircraft. 

141-43, 144 ill., 145, 178, 280 

145-46 

339 

280,339 

ill,, 280, 339, 341, 342, 343, 360 

339, 341, 342, 343, 360 

295,303-04,309-10,313-14,321,326,3?&, 

331,332, 333, 334, 335,336 

McMurtry, Tom, 168,204, 212,214,241,250, 

257 ill., 345, 353 

McTigue, John, 154,205 

Magruder, William M., 189 

Mallick, Donald, 143-44, 152, 187,257 ill., 347, 

348,349,350,351,352,353,354,355,356 

Manke, John, 159,160,162,164,166,167,168, 

257 ill., 340, 341, 342, 343-44, 352 

Manned Spacecraft Center (MSC), 145, 169 

Manned spaceflight. See Apollo, Gemini, 

Mercury programs, Columbia and Enterprise. 

Manson, Hugh, 185 

Marshall Space Flight Center (MSFC), 250,256 

Martin, Isabel1 K., 9 

Martin, John F., 36, 304 

38 1 
ON THE FRONTIER 

Manin Marietta Col;p., 120, 156-57, 164, 165, 

166, 170 

Massachusetts Institute of Technology (MIT), 

119,218, 219 

Matay, Doll, IO 1 

Matheny, Cloyce E., 9 

Matranga, Gene, 80,91, 142, 190, 191 

May, Eugene F., 28 ill., 299 

Mayer, John, 16 

Me 163 (German interceptor), 54 

Media coverage, NASA, 401, 112, 240, 243, 

Mercury Mark 11. See Gemini program. 

Mercury project, 103, 112, 116-17, 131, 136 

Military combat aircraft. See Air Force, US.; 

Army Air Forces; Dryden Flight Research 

Center: High-speed Flight Station; Langley Research Center; National Advisory 

Committee for Aeronautics; National 

Aeronautics and Space Administration; 

Navy, U.S. and names of individual aircraft. 

244,248,250,251 

Minalga, George P., 9 

Mini-Sniffer (RPRV), 216, 281 

Mirage (delta wing aircraft), 57 

Moise, John, 72 

Mojave Desert, xii ill. 

Moss, Frank, 235 

Muroc Air Force Base, xvii, 23-27,41, 42. See 

Muroc Army Air Field, xvi, xvii-xviii, 6, 7, 9 

Muroc Flight Test Unit, 14-15, 20-30, 32-34, 

262, 263. See also High Speed Flight Station. 

also Edwards AFB. 

35, 37-38, 41, 42, 43, 103, 255, 256-57, 

Murray, Arthur (“Kit”), 72, 293, 324 

NACA-Edwards. See High Speed Flight Station. 

NB-52B (Stratofortress; rocket aircraft launch 

ship), 283 

NKC-l35A(Stratotanker; researchtestbed),280 

Nash, J.S., 319 

National Advisory Committee for Aeronautics 

(NACA), 4,6,33, 101,226,233 

civil aeronautics, 3 1, 62, 222-23 

military aircraft testing, 12-13, 19, 31, 36, 

41-43,47,55-56,60,88-98, 109,285,299, 

304,315,317,319 

National Aeronautics and Space Administration 

civil aeronautics, 188,204,207,222-23,225, 

manned spaceflight, 101-02, 131, 138, 140, 

military aircraft programs, 93,95,98, 1 18-19, 

181-82, 185, 186, 187-88,207-09,213,220, 

National Hypersonic Flight Research Facility 

(NASA), 3,42, 106, 252-54,277 

226,233 

151-52, 152-53, 154-55, 160, 163-64, 166, 

169, 170, 177-78, 240 

227, 228, 230, 232-233, 347, 349 

(NHFRF), 170,235 

382 

National Sonic Boom Program, 186 

Naval Ordnance Test Center, 150 

Navy, U.S. 

arid NACA, 27, 34, 47, 48, 59-60, 64, 65, 

and NASA, 136, 180,203,228,231-32,233, 

67-68, 87, 108, 109 

251,255 

Nixon, Richard M., 189 

North American Rockwell, xi, 92, 96, 109-10, 

112, 119, 120, 125, 137-38, 170,204,216, 

239,247 

North Base, Muroc. See Muroc AFB. 

Northrop, John, xvi, 54 

Northrop, Inc., xi, 7, 37, 88, 152, 154, 155, 

157, 158, 159-60, 161, 170 

Office of Advanced Research and Technology 

(OART), 106, 109,125, 153,160,164,177, 

181, 198,213,218,233,256,273 

Office of Aeronautics and Space Technology 

(OAST), 106, 169,213,256,268,273 

Office of Manned Space Flight (OMSF), 106 

Office of Space Science and Applications 

(OSSA), 106 

Olstad, Walter B., 252 

Ottinger, C. Wayne, 142 

Outstanding Leadership Medal, NASA, 128 

P-38, 5 ill. 

P-47 (Thunderbolt; fighter), 87 

P-51, P-515, P-51H (Mustang; fighter), 5 ill., 

P-80 (Shooting Star; fighter), 15, 17, 18, 62 

P-1101 (experimental German aircraft), 7 

PA-30 (Comanche; NASA liaison and RPRV), 

Paine, Thomas O., 204 

Painter, Weneth D., 208 

Paresev (kite-parachute research aircraft), 137, 

Payne, Dick, 72 

Personnel, NACA, 9, 10- 11,23. See also Muroc 

FTU. 

Personnel, NASA, 102, 106, 132, 133, 254-55, 

273 

Peterson, Bruce, 139, 152, 158-59, 161,257 ili., 

330,331,339,360 

Phillips, William H., 58-59, 92 

Piloted Lowspeed Tests (PILOT), 155 

Pilotless Aircraft Research Division, Wallops 

Island (PARD), 14, 31,32, 55 

Pitch-up problem, 36-37,47,48,49,50,51 ill., 

57,59 

Pontiac tow vehicle, 150-5 1 

Popson, Ray, 52 

Powell, Cecil, 164, 342, 343 

Pratt & Whitney Co., 193, 220 

Precision Recovery Including Manuevering Re- entry, 155, 156, 170 

19, 29, 51, 87 

212, 213 ill., 223, 225, 281 

138 ill., 139-40, 256, 280 
L 

Present, Stu, 146 

Quesada, Elwood, 188 

Quiet Short-Haul Research Aircraft (QSRA), 

252 

Radar, 110-1 1 

Ream, H. E. (‘‘Bud), 144 

Reed, Robert D., 148-49, 210-11, 213 

Reed, Sylvanus Albert, Award, 128 

Reeder, J., 324 

Reid, Henry J. E., 7, 24, 25 

Remotely piloted research vehicle (RPRV), 

Republic Aircraft Co., 88, 109, 281 

Research aircraft. See names of individual aircraft, NACA and NASA research centers, 

and appendices. 

Research Airplane Committee, 109. See also 

Research Airplane Projects Panel (RAPP), 3 1- 

210-16, 281 

X-15. 

33, 50, 52, 56, 57, 60, 75, 88-89, 92, 94, 

109 

Richards, Charles, 138 

Ridley, Jack L., 13, 15, 16, 17 ill., 287, 293 

Rockwell International. See North American 

Rockwell. See North American Rockwell. 

Rogallo, Francis M., 137, 256 

Rogers, J., 349 

Rogers Dry Lake, xi, xiv-xv, xvi, 18 1, 244, 249 

Roland, Alex, 60 

Rushworth, Bob, 120,330,331,332, 333,334 

Russell, Jack, 17 

Ryan Firebee 11, 215 

SB2C (Helldiver; dive bomber), 87 

SR-71A, SR-7IB (Blackbird; strategic reconnaissance aircraft), 190, 191, 192, 193, 194, 

196, 199, 233 

Rockwell. 

SST, 177, 178-80, 181, 182, 185, 186, 188, 189, 

193, 196 

SVdD, SV-51, SV-5P (Martin lifting bodies; see 

also X-F4A), 148, 155, 156-57, 163-64, 

165-66 

Sadoff, Melvin, 38 

Safety research, 72-73, 89, 222-26 

Samet, Arthur, 43 ill. 

Sanger, Eugen, 106-07, 128 

Satellite studies, 102, 132 

Scherer, Lee R., 105, 237 ill., 238, 254, 261 

Schilling Trophy, 128 

Scobee, Francis R., 168, 345 

Scott, David R., 106,232,235,236 ill., 238,26 1 

Seamans, Robert, 126, 184 

Semitailless aircraft. See Configuration, aircraft. 

Senate. Committee on Aeronautical and Space 

Sciences, 134 

INDEX 

Shepard, Van, 187,347 

Short-takeoff-and-landing aircraft (STOL), 

178,257 

Slayton, Donald (“Deke”), 145, 250 

Smith, George. 12 

Smithsonian Institution, 39, 152, 161 

Sorlie, Donald, 152, 158, 339 

Soule, Hartley A., 7, 13, 18, 21, 24, 25, 31-33, 

Sound barrier. See Supersonic research. 

South Base, Muroc. See Muroc AFB. 

Soviet Union, 112, 168, 178, 188 

Spacecraft Technology and Advanced Reentry 

Spacecraft, unmanned, 101, 102, 108 

Spacecraft, winged, 101, 122-23 

Space race, 101, 112, 168 

Space science programs, 119, 122-23 

Space Shuttle, XI, 108, 116, 136, 172, 197,220, 

238-39, 256, 357-58. See also Columbia and 

E nterplzre. 

lifting body research, xix, 161,162, 163, 164, 

X-series, 81 

34, 38, 39, 42,47-48, 85, 107, 109, 119 

Tests (START), 155 

167, 168-70 

Sperry Flight Systems Div., 218 

Sperry, Lawrence B., Award, 128 

Stabilizer, 2 1 

Stack, John, 6, 7, 14, 19, 34, 35, 119 

Stephens, Robert, 293 

Stewart, James T., 125 

Stillwell, Wendell H., 71, 79 

Sturmthal, Emil, 187, 347, 348 

Supzrcritical wing, 202-10, 256 

Supersonic flight research, 98. See also SST. 

Blackbird program, 189-99 

configuration studies, 13, 21-22, 54-55, 75, 

speed studies, 11-12, 15-19, 47, 63, 64n, 65, 

X-series, xviii, 3-4,6-7, 8,9-11, 13-14, 79-85 

Swann, Michael, 353 

Sweptwing aircraft. See Configuration, aircraft. 

Syvertson, Clarence, 147, 148, 169, 252 

T-33, T-33A (Shooting Star; trainer), 158, 228, 

T-37 (jet trainer), 225 ill., 226 

T-38, T-38A (Talon; trainer), 182-83, 194,227, 

TF-8A (Crusader; NASA research aircraft), 

TF30-P9. See Engines, aircraft. 

TF-5 1 D (Mustang; trainer), 28 1. See also P-5 1. 

TF-1O4G (Starfighter; trainer), 282. See also 

Tu-144, (Soviet SST), 189 

Tactical Fighter Experimental program (TFX), 

82,84 

67-7 1, 74, 76-78, 84 

229,230,360 

243, 245, 246, 247 

204-05, 280 

F-104. 

228 

383 
P * s c 

ON THE FRONTIER 

Telemetry, 9-10, 15, 11 1, 184 

Test pilot, 42 ill., 52n, 112, 230, 232, 257 ill. 

See also names of individual pilots. 

pilot safety, 9, 31, 115 

pilot training, 55, 95 

Thompson, Mickey, 150 

Thompson, Milton, 97, 136, 138, 139, 150, 151, 

158, 163, 169, 180, 210-11, 257 ill., 333, 

334,339,360 

Toll, Thomas, 15 1, 204 

Transonic Aircraft Technology program 

Transonic flight research, 4, 98, 172, 201-02, 

configuration studies, 59-60, 88, 178, 207, 

X-series, 13, 21, 39, 54-55, 82, 84 

(TACT), 172, 178, 207-09, 250 

229-30, 250-51 

208 

Transportation, Dept. of, 227 

Tride7t (French interceptor), 97 

Truly, Richard H., 242, 247, 358 

Truman, Harry S., 21 

Truszynski, Gerald M., 10 ill., 13, 16, 17 ill., 43 

Turbulence, clear air, 223, 226-27 

U-2 (strategic reconnaissance aircraft), 194, 

196, 226 

United States. See Space race. 

Uppstrom, J., 353 

Ursini, S., 349, 353 

Vandenberg, Hoyt, 19 

Vensel, Joseph, 13, 17 ill., 43 ill., 45 ill., 46, 72 

Vertical-takeoff-and-landing aircraft (VTOL), 

Victory, John, 45 ill. 

Viking Mars lander, 227n 

WB-57F (high-altitude research aircraft), 226 

Wake vortex research, 223, 224, 224-226 

Walker, Joseph A., 94,97, 143, 144, 182, 183, 

ill., 45 ill., 46, 110-1 1 

102, 141-42, 178, 257 

184,360 

D-558-1, 302, 303, 312 

X-series, 52, 58-59, 72, 291, 293, 295, 308, 

X-15 series, 122, 329, 330, 331, 332, 333 

Wallops Flight Center (WFC), 252,254. See also 

Walls, Warren A., 9 

Walsh, Lloyd, 142 

Washburn Observatory, 119 

Webb, James E., xix 

Weightlessness, 76, 116 

Weil, Joseph, 91, 169, 190 

Welch, George, 91 

Whitcomb, Richard, 91, 96, 202-07, 210, 224, 

317, 320. 323, 324-25 

Pilotless Aircraft Research Div. 

25 1, 256 

White, AI. 182, 183, 184. 329. 330. 331 

White, Bob, 115 

White, Thomas D., Space Trophy, 128 

Whiteside, Walter, 15 1 

Williams, Walter C., 10 ill., 17 ill., 26 ill., 31, 

32.43 ill., 44, 45 ill., 72, 103-04, 148, 168, 

26 I 

aircraft improvements, 29, 88, 92, 95 

and Headquarters, 35,67,68, 103, 141, 142, 

and military, 24-27, 65, 91, 97, 154 

X-series, 9, 10, 14, 15, 16, 18,36,38,54,55, 

Wilson, Joe, 139 

Wind tunnel, 4, 37, 39, 56,82, 84,87,96, 115 

128, 138, 150,203,207,231 

Wing design, 21, 31, 47, 48-51, 55-57, 88-89. 

See also Configuration, aircraft and Supercritical wing. 

Woods, Merle, 72n 

Woods, Robert, 107 

Woolams, Jack, 9, 1 1, 285 

World War 11, xvi, xvii 

Wright Brothers Memorial Trophy, 207 

Wright-Patterson AFB, Oh., xvi, 13, 187 

Wyoming, Univ. of, 227 

X-series, 6,8,47. See also Supersonic flight research and names of individual research 

237 

60, 75, 78, 82, 85, 102-03 

aircraft. 

X-1, xviii, 3, 6, 7, 8, 9, 11, 12, 13-18, 19 ill., 

20 ill., 21-22, 27, 30 ill., 31n, 34, 39, 49 

ill., 63, 279, 285-92 

X-1-3, 65, 66 ill., 71, 85 

X-1 A, 19,67,69,70 ill., 71n, 72,73-74,79,80, 

279,285,292,293,360 

95 

X-lB, 19, 71,72,73, 74,75,79, 112,279,293- 

X-ID, 19,65,66n, 67, 71, 72,295 

X-2, 7, 12 ill.. 39, 47, 49, 55, 64, 73, 74 ill., 

X-3,30,39,47,48,49,50,51,52,57-58,59 ilL, 

X-4,37-39,47,48,49 ill., 50, 51,52,54,55 ill., 

X-5, 7, 3 1, 39, 47, 48, 49 ill., 50, 5 1-52, 53 ill., 

X-15, xix, 3, 41,46, 47-48, 55,64n, 75,78, 79, 

81, 85, 90, 95, 96, 97, 98, 101, 102, 103, 

104-05, 106-10, 11 1 ill., 112, 113 ill., 114 ill., 

115-19, 124-25, 126-29, 131, 132, 134,227, 

X-15A-2, 109, 115, 119-20, 121 ill., 122, 279, 

X-lE, 79, 80, 163, 279, 295, 360 

75-76, 76-77, 78, 82, 107, 315-16 

82, 85, 92, 94, 279, 317-18 

58, 279, 319-21 

54, 279, 323-26 

231, 279, 329-37, 360 

329 

X-15-3, 122-25, 279, 329, 360 

X- 15 follow-on program, 1 18- 19 

X-20A. See Dyna-Soar. 

X-24A (SV3P), 163-65, 166, 174 ill., 280, 339, 

340,341, 342 

X-24B, 164, 165-68, 175 ill., 280, 339, 340, 

384 
34 1,342 

X-24C, 170-7 I 

XB-35 (Flying Wing; experimental bomber), 

XB42 (Mixmaster; experimental bomber), xviii 

XB-70, XB-7OA. (Valkyrie; supersonic research 

aircraft), xix, 172, 176 ill., 180, 181, 182, 

185, 186, 187, 189, 190, 196, 198, 226, 

XFZR-I (Dark Shark; experimental fighter), 

XF2Y-I (Sea Dart; experimental fighter), 57 

XF-91 (Thunderceptor; interceptor), 88 

XF-92A (Dart; research aircraft), 7,30,39,47, 

48, 49 ill., 50, 5 1, 52, 56 ill., 57, 9 1, 292, 

327,360 

xviii 

256, 280, 347-48 

xviii 

XLR-I 1. See Engines, aircraft. 

XLR-99. See Engines, aircraft. 

XP-59A (Airacomet; research aircraft), xvi-xvii 

XP-80 (Shooting Star; experimental fighter), 

XP-8 1 (experimental fighter), xviii 

XS 1, XS2, XS-3, XS-4. See X- 1, X-2, X-3, X-4. 

XV-15 (VTOL research aircraft), 251,252,256, 

xvii 

284 

YB-49 (Flying Wing; experimental bomber), 

YC-14 (STOL research aircraft), 233 

YC-15 (STOL research aircraft), 233 

YF-5A. See F-5A. 

YF-12, YF-IPA, YF-I2C (Blackbird; experimental interceptor), xix, 169, 176 ill., 178, 

189, 190-94, 195 ill., 196-99,222,226,242, 

253 ill., 256, 349-56 

xvii, xviii 

YF-16. See F-16. 

YF-17 (Cobra; experimental fighter), 228, 230, 

YF-102, See F-102. 

YF-I04A. See F-104. 

YF-107A. See F-107. 

Yancey, Roxanah B., 9 

Yeager, CharlesE., 13-14, 15-16, 17 ill., 18, 19, 

231, 232 ill., 283 

39,69, 70-71,97, 152, 164, 168, 251,286, 

287,288,289,291,292,319 

Young, John, 251 

Young, Ray, 349,350,351,352,353,354,355, 

Youngblood, Harold H., 9 

Ziegler, Jean, 292, 295 

356 

385 
R I 

The Author 

Richard P. Hallion is Center Historian of the Air Force Flight Test 

Center, Edwards AFB, California. A native of Washington, D.C., he 

received his B.A. in history from the University of Maryland in 1970, 

followed by the Ph.D. in 1975. From 1974 through 1980, he served as 

Curator of Science and Technology (later Curator of Space Science and 

Exploration) at the National Air and Space Museum of the Smithsonian 

Institution, Washington, D.C. He taught history, perspectives on technology and society, and aeronautical engineering for the University of 

Maryland and was a visiting fellow at Yale University. He has been a 

consultant on museum and exhibit design and is the author of numerous 

works in aerospace history, including Supersonic Flight: Breaking the Sound 

Barrier and Beyond (1972); Legacy of Flight: The Guggenheim Contribution to 

American Aviation (1977); The Wright Brothers: Heirs of Prometheus (1978); 

with Tom D. Crouch, Apollo: Ten Years since Tranquillity Base (1979); Test 

Pilots: The Frontiersmen of Flight (198 1); and Designers and Test Pilots (1983), 

a volume in the Time-Life Epic of Flight Series. 

Hallion is active in professional societies including the American 

Institute of Aeronautics and Astronautics, the Society for the History of 

Technology, the Air Force Historical Foundation, the Air Force Association, 

the U.S. Naval Institute, the American Astronautical Society, the American Aviation Historical Society, and the Aviation-Space Writers Association. He is a member of the Wings Club. He has received the AIAA 

History Manuscript Award, the Dr. Robert H. Goddard Essay Award, and 

writing citations from the Aviation-Space Writers Association. He was 

named a Distinguished Lecturer of the American Institute of Aeronau- 

'tics and Astronautics for the years 1982- 1984. He received a Daniel and 

Florence Guggenheim Foundation fellowship in 1973 and 1974- 1975. 

He lives in Lancaster, California. 
The NASA History Series 

HISTORIES 

Anderson, Frank W., Jr., Orders of Magnitude: A History of NACA and NASA, 1915-1 980 (NASA 

Benson, Charles D., and William Barnaby FaheTty, Moonport: A History of Apollo Launch Facilities 

Bilstein, Roger E., Stages to Saturn: A Technological History of the ApollolSaturn Launch Vehicles 

Boone, W. Fred, NASA Offwe of Dejime Affairs: The First Five Years (NASA HHR-32, 1970, 

Brooks, Courtney G., James M. Grimwood, and Loyd S. Swenson, Jr., Chariots for Apollo: 

Byers, Bruce K., Destination Moon: A History of the Lunar Orbiter Program (NASA TM X-3487, 

Compton, W. David, and Charles D. Benson, Living and Working in Space: A History of Skylab 

Corliss, William R., NASA Sounding Rockets, 1958-1968: A Historical Summary (NASA SPEzell, Edward Clinton, and Linda Neuman Ezell, The Partnership: A Histmy of the Apollo-Squz 

Ezell and Ezell, On Mars: Exploration of the Red Planet, 1958- 1978 (NASA SP-4214, in press). 

Green, Constance McL., and Milton Lornask, Vanguard: A History (NASA SP-4202, 1970; also 

Hacker, Barton C., and James M. Grimwood, On the Shoulders of Titans: A History of Project 

Hall, R. Cargill, Lunar Impact: A History of Project Ranger (NASA SP-4210, 1977). 

Hartman, Edwin P., Adventures in Research: A History of Ames Research Center, 1940-1965 (NASA 

Levine, Arnold, Managzng NASA in the Apollo Era (NASA SP-4102, 1982). 

Newell, Homer E., Beyond the Atmosphere: Early Years of Space Science (NASA SP-4211, 1980). 

Roland, Alex, Model Research: A History of the National Advisory Committee for Aeronautics 1915- 

Rosenthal, Alfred, Venture into Space: Early Years of Goddard Space Flight Center (NASA 

Rosholt, Robert L., An Administrative History of NASA, 1958-1963 (NASA SP-4101, 1966). 

Sloop, John L., Liquid Hydrogen as a Propulsion Fuel, 1945-1959 (NASA SP-4404, 1978). 

Swenson, Loyd S., Jr., James M. Grimwood, and Charles C. Alexander, This New Ocean: A 

SP-4403, 2d ed., 1981). 

and Operations (NASA SP-4264, 1978). 

(NASA SP-4206, 1980). 

multilith). 

A HistMy of Manned Lunar Spacecraft (NASA SP-4205, 1979). 

1977, multilith). 

(NASA SP-4208, in press). 

4401, 1971). 

Test Project (NASA SP-4209, 1978). 

Washington: Smithsonian Institution Press, 1971). 

Gemini (NASA SP-4203, 1977). 

SP-4302, 1970). 

1958 (NASA SP-4303, in press). 

SP-4301, 1968). 

History of Project Mercury (NASA SP-4201, 1966). 

REFERENCE WORKS 

Aeronautics and Space Report of the President, annual volumes 1975- 1982. The Apollo Spacecrafi: 

Astronautus and Aeronautics: A Chronology of Sczence, Technology, and Policy, annual volumes 196 1 - 

Dickson, Katherine M., ed., History of Aeronautics and Astronautics: A Preliminary Bibliography 

Hall, R., Cargill, ed., Essays on the History of Rocketry and Astronautics: Proceedings of the Third 

through the Sixth History Symposia of the International Academy of Astronautics (NASA CP-2014, 2 

vols., 197'7). 

Hall, R. Cargill, Pr ect Ranger: A Chronology UPUHR-2, 1971, multilith). 

Looney, John J.. ez, Bibliography of e Books and Articles from Non-Aerospace Journals. 1957- 

1977 (NASA HHR-51, 1979, mu1 

Roland, Alex, A Guide to Research in NASA History, (NACA HHR-50, 6th ed., 1982, available 

from NASA History Office). 

Skylab: A Chronology (NASA SP-4011, 1977). 

Van Nimmen, Jane, and Leonard C. Bruno, with Robert L. Rosholt, NASA Historical Data Book, 

Wells, Helen T., Susan H. Whiteley, and Carrie E. Karegeannes, Origins of NASA Names (NASA 

A Chronology (NASA SP-4009, vol. 1, 1969; vol. 2, 1973; vol. 3, 1976; vol. 4, 1978). 

1976, with an earlier summary volume, Aeronautics and Astronautics, 1915-1960. 

(NASA HHR-29, 1968, rnultilith). 

1958-1968, vol. 1, NASA Resources (NASA SP-4012, 1976). 

SP-4402, 1976). 

Recent volumes are available from Superintendent of Documents, Government Printing Office, 

Washington, DC 20402; early volumes from National Technical Information Service, Springfield, 

VA 22161. 

x