National Aeronautics and 

Space Administration 

Dryden Flight Research Center 

P.O. Box 273

Edwards, California 93523 

AC 661-276-3449 

FAX 661-276--3566 

pao@dfrc.nasa.gov FS 1998-09-02 DFRC 

Imagine a new breed of aircraft that could travel 3750 

mph (at sea level) and make a trip from Los Angeles to 

New York City in a little more than 45 min.

 NASA is working to make these aircraft of the 

future possible through research into the world of 

hypersonics, or flight at speeds faster than five times 

the speed of sound.

 One of these exciting areas of research is the 

Pegasus Hypersonic Experiments project, managed by 

the NASA Dryden Flight Research Center, Edwards, 

CA.

 The experiment consists of a smooth, informationgathering “glove” installed on the first-stage wing of 

the Pegasus Space Launch Vehicle, which reaches 

speeds of Mach 8 and altitudes of 200,000 ft. The 

glove is bonded to the right wing and wraps from the 

underside of wing, over the leading edge and onto the 

upperside, although it does not cover the wing completely.

 The experiment will gather information about how 

the air flows over the Pegasus® wing. Scientists are 

particularly interested in the transition of air from 

smooth (laminar) to turbulent flow. The goal of the 

experiment is to discover when the airflow over the 

wing becomes turbulent and why. 

® Pegasus is a registered trademark of Orbital Sciences Corp., Dulles, Va.

 Airflow has a great impact on how hot vehicles 

get. Turbulent air generates a lot of heat because of 

increased friction, which can cause burns on aircraft.

 The hypersonic X-15 experienced such problems 

due to turbulence-induced friction. In addition, 

turbulent air creates more “drag,” slowing down 

aircraft or making them less efficient. 

The Orbital Sciences Corp.'s Pegasus booster rocket is mated to 

Dryden's B-52. Orbital's L-1011 now serves as the Pegasus 

mothership. 

Data from the Pegasus® glove experiment also will 

include temperature, heat transfer and pressure measurements, as well as reconstruction of the Pegasus® flight path. 

This experiment will provide critical information that can’t 

be obtained anywhere else, as wind tunnels here on the 

ground can’t adequately simulate both the hypersonic speeds 

and atmospheric conditions the Pegasus® booster encounters. 

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 A secondary goal for the program is to provide 

engineers with valuable experience in instrumenting 

and testing hypersonic vehicles. 

At about 38,000 feet, the Pegasus booster drops from the E-1011 

aircraft, and its engine ignites. The PHYSX glove gathers data 

for about a minute and a half before the first stage burns out and 

falls away. The Pegasus and its payload continue their ascent. 

Flight Scenario

 The hypersonic glove experiment currently is 

scheduled to fly in October 1998. Pegasus®’ primary 

goal for the mission, which will originate from the 

Cape Canaveral Air Force Station, Cape Canaveral, 

FL., is to launch a commercial satellite payload. 

Pegasus® will carry the glove aloft as a secondary 

mission that will not interfere with the launch 

vehicle’s primary goal.

 Once the first stage Pegasus® booster rocket 

launches from its L-1011 mothership, the highly 

instrumented glove will be able to gather information 

about flight at high speeds and altitudes. Sensors in the 

glove will only be able to gather information for about 

a minute and a half before the first-stage of the rocket 

burns out and is jettisoned.

 All information the glove obtains will be transmitted to the ground through a radio signal as the glove 

will not be recovered. To make transmitting the data 

possible, engineers at the NASA Langley Research 

Center, Hampton, VA., developed a special data 

acquisition, compression and processing system. In 

January 1995, Dryden’s F-15 aircraft tested the system 

during a series of flights over Edwards Air Force 

Base, CA. 

Glove

 Two Pegasus® Hypersonic Experiment gloves were 

manufactured for the program — one that will fly 

aboard the Pegasus® booster rocket and one earmarked 

for thermal ground tests. Both gloves are made of 

nickel-plated steel.

 The ground-test glove was mounted on a plywood 

and fiberglass structure for a series of tests that concluded May 30, 1996. The glove was painted a flat 

black to maximize heat absorption. During the tests, 

engineers precooled the glove and heated it in NASA 

Dryden’s Flight Loads Laboratory, simulating the heat 

the glove will experience during its first-stage flight 

profile. The tests revealed that the glove is hardy 

enough to survive the intense heat it will experience 

while traveling at eight times the speed of sound.

 The flight-test glove is mounted on balsa wood and 

surrounded by a drag-reducing thermal protection 

system structure made of Space Shuttle tile material 

that blends the glove into the wing. NASA Ames 

Research Center, Moffett Field, CA, supplied the 

thermal protection system, which dissipates heat. The 

glove was mounted to the Pegasus® wing at Dryden. 

The Pegasus booster rocket will be secured to its 

L-1011 launch vehicle at the Orbital Sciences Corp.’s 

Vehicle Assembly Building at Vandenberg Air Force 

Base, CA 

The experimental glove is made of nickel-plated steel and 

carries pressure and temperature instrumentation, among other 

instruments. 

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The nickel-plated steel glove, shown here undergoing heat tests in 

1996, is bonded to the right wing and wraps from the underside of 

wing, over the leading edge and onto the upperside, although it 

does not cover the wing completely. 

The glove carries a variety of traditional and highfrequency sensors capable of functioning during the 

flight conditions the Pegasus® rocket will experience. 

The sensors will give engineers a variety of information like acceleration, air flow, pressure, temperature 

and strain. Many of these sensors were evaluated in 

July 1994 aboard an earlier Pegasus® mission. The 

mission verified that the sensors do not interfere with 

the airflow over the Pegasus® wing and that the vibrations the sensors will experience during flight will not 

interfere with obtaining accurate data. 

Roles and Responsibilities

 Dryden is providing overall management of the 

glove experiment, glove design and buildup. Dryden 

also is responsible for conducting the flight tests. 

Langley is responsible for the design of the aerodynamic glove as well as development of sensor and 

instrumentation systems for the glove. Other participating NASA centers include Ames; Goddard Space 

Flight Center, Greenbelt, MD.; and Kennedy Space 

Center, FL. Orbital Sciences Corporation, Dulles, VA, 

is the manufacturer of the Pegasus® vehicle, while 

Vandenberg Air Force Base, CA serves as a prelaunch 

assembly facility. 

Pegasus Background

 First flown in 1990, Orbital Sciences Corp.’s 

Pegasus® rocket supports a wide range of missions, 

including space technology validation, earth science 

and space physics experiments, hypersonic flight 

research, earth imaging, communications and planetary exploration. The three-stage Pegasus® launch 

vehicle is carried aloft by the company-owned L-1011 

“Stargazer” aircraft to a point approximately 40,000 ft 

over open ocean areas, where it is released and then 

free-falls in a horizontal position for five seconds 

before igniting its first stage rocket motor. With the 

aerodynamic lift generated by its delta wing, the small 

rocket achieves orbit hundreds of miles above the 

Earth in approximately ten minutes. Pegasus is capable of carrying payloads up to 1,100 lb.. 

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