NASA SP-4003 

SPACE MEDICINE 

IN PROJECT MERCURY 

By Mae Mills Link 

OFFICE OF MANNED SPACE FLIGHT 

Scientific anJ Technical Information Division 1 9 6 5 

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 

Washington, D.C. 










SPAOE MEDICINE: A CRrnCAL FACTOR IN MANNED BPAOE FLlOUT 3 

BIOLOGICAL REQUIREMENTS 

In November 1957, the month in which the President's Scientific 

Advisory Committee was established, NACA set up a Special Committee on Space Technology under· the cha.irmn.nship o-f Dr. H. 

Guyford Stever of the Massachusetts Institute of Technology. 

The Stever Committee met for the first time on February 13, 

1958, and estnblished seven working groups. The group named 

to study human fttctors and training was beaded by Dr. Vv. Rn,ndolph Lovelace II, director of the Lovelace Foundation for Medical Education and Research.8 This group concerned itself with 

the scientific and nonmilitary biomedicalr'equirements for manned 

space flight, as well as othet· biological factors that should be part of 

a, national space program.* 

The final report mts dated October 27, 1958, the month in ,,·hich 

NASA became operational.u Briefly, it considered how best. to 

utilize man's capabilities in space exploration and outlined the 

means by which the new space agency should develop resourc.es 

in life-sciences research. Thirteen techn arens were discussed: 

Program administration; acceletation; high-intensity radiation in 

spa.ce; cosmic t'adiation; nuclear propulsion; ionizatjon effects; 

human information processing and communication; displays; 

closed-cycle living; baJloon simulators; space capsules; crew selection and training; and research centet·s and 1aunching sites. 

The report noted that because of the. rapid development of rocket. 

technology in missile programs, manned satellites and space vehic.Jes had fl. potent.iaJ for rapid and revolutionary progress. Concurrent biomedical a.ud physical research and development to detel'mine man's capabilities in space would be necessnry. Accot'ding to the r'eport: 

The ultimate and unique objective in the conquest of space is the early successful flight of 

man, with all his capabilities, into space and his safe return to earth. Just as man has achieved 

an increasing control over his dynamic environment on earth and in the atmosphere, he must 

now achieve the ability to live, to observe, and to work in the environment of space.

•serving with Dr. Uvelace on the ad hoc committee were A. Scott Crossfield, North American Aviation, Inc.; Hubert M. Drake, Higb-Speed Flight 

St tion, NACA; Brig. Gen. Don D. Flickinger, USAF (MC); Col. Edward B. 

Giller, USA ; Dr. James D. Hardy, U.S. Naval Air Development Center: Dr. 

Wright Haskell Langham, Los AlamosScientific Laboratory; Dr. Ulrich 

. Luft, Head, Physiology Department, Lovelace Foundation for Medical 

Education and Research; and B Qyd C . M yers I I ( Secretary) , NACA. 

_ical 


















Pre-Mercury Heritage in Biotec

UN TIL THE CONGRESS CLARIFIED SPACE ROLES and 

Department of Defense effort in missile and sp

variegated and geared for response to a potential m

that had been presented by Sputnik-the demonstr

rocket technology. 

On January 13, 1958, preceding the establishm

under the Space Act, the Secretary of Defense, Ne

testified before the House Armed Services Committ

posed to establish· within the Department of De

vanced Research Projects Agency (ARPA) to be r

the unified direction and management of the anti-

program and for outer· space· projects.* The pro

proved by the President on March 27, 1958. ARPA 

to undertake space projects, including the launch

satellites and five space probes as part of the Unite

tribution to the International Geophysical Year. 

When NASA was declared operational on Octob

sponsibilities for the remaining U.S. IGY satellite 

were transferred to NASA by Executive order. Ea

tember 17, 1958, a joint NASA- ARPA manned sate

been established to make recommendations for a 

flight program.1 This would be Project Mercury. 

Meanwhile, the year following Sputnik had been 

research and development took unprecedented fo

within the services. In that period two potentially w

lite research concepts were emerging within the D

*According to "A Chronology of Missile and Astronaut

lished in House Report 6'1 (87th Cong., 1st sess.), p. 36, th

announced approximately a month before, on Dec. 5. 

22 
In July 1957, preceding Sputnik, the U.S. Air Force Scientific 

Advisory Committee arranged through the Rand Corp. in Los 

Angeles, Calif., to hold a 2-day conference to discuss the state of 

the art in jet propulsion and space technology. Representatives 

from NACA also attended the meeting. The life-sciences agenda 

for the meeting was prepared by Brig. Gen. Don D. Flickinger, 

Command Surgeon, ARDC, and Dr. Albert Hetherington, chief 

scientist on his staff. 

Out of the meeting came the conclusion that, given vehicular 

reliability, no additional life-sciences knowledge was needed for 

normal orbital flights. Initial testing for environmental control 

Missile nose cones, 1953-1957 Manned-spacecraft concept, 1957 

Aerodynamics research contributing to Project Mercury. 

1772-17() ()..-65--3 













































After the plastic TTUJld had hardened, it was finished with fibrous material (above). 

Then the contour couch was clamped to the metal seat and fitted with harness and 

restraining straps (below) in preparation for installation in Mercury spacecraft. 

























































flight, President Kennedy had announced that Lt. Col. J

would be the prime astronaut for the first manned orbi

to take place shortly, with Lt. M:. Scott Carpenter 

Capt. Donald Slayton would be the prime astronaut for 

manned orbital mission with Lt. Comdr. Walter 

backup.~ 

During the following days, however, it appeared th

nouncement might have been premature in the light 

findings of the Enos flight. The tension of those day

described unofficially to the author. It must have bee

of uncertainty as to the proper course of action to tak

first manned orbital flight was scheduled for Decembe

Fortunately this potential medical crisis did not b

blown. Eminent cardiologists were asked to review t

and biological data obtained during the orbital fligh

to determine the reason for the arrhythmia, if possib

separate it from the influences exerted by weightlessne

flight. It was found that the difficulty lay with the in

tion, and that the data were therefore invalid. Acco

was recommended that the manned orbital flight 

scheduled.5 

MEDICAL IMPLICATIONS OF THE CHIMPANZEE 

The two chimpanzee flights in Project Mercury \Ye

significant medical data. The suborbital flight of Ham 

out complications, but it was considerably less complex 

orbital flight. 

In the Mercury-Atlas 5 (MA-5) orbital flight, Enos 

a complex multiple operant task as he twice orbited 

The 42-pound subject, whose age was estimated to be 

had been exposed to simulated launch accelerations on 

fuge at the University of California. He had also 

subject for a laboratory model of a 14-day flight. Over 

period he had received a total of approximately 1,26

training, of which 343 hours were accomplished unde

conditions in a model of the actual couch used in flight
SPACE MEDICINE IN 1961-62 129 

The success of the two 

manned suborbital flights 

still left much unknown 

about physiological responses to orbital flights 

with their extended periods 

of weightlessness. To find 

some answers prior to 

manned orbital flight, the 

chimpanzee Enos-shown 

at right with biosensors attached to his body-was 

sent aloft November 29, 

1961, for two orbits. His 

flight confirmed normal 

bodily functions and motor 

abilities in weightlessness. 

According to Henry, the results of the two animal flights (Ham 

and Enos) showed that : 

(1) Pulse and respiration rates, during both the balUstic (MR-2) and the 

orbital (MA-5) flights, remained within normal limits throughout the 

weightless state. E1fectiveness of heart action, as evaluated from the 

electrocardiograms and pressure records, was also unaffected by the flights. 

(2) Blood pressures, in both the systemic arterial tree and the lowpressure system, were not significantly changed from prefl.lght values during 

3 hours of the weightless state. 

(3) Performance of a series of tasks involving continuous and discrete 

a voidance, fixed ratio responses for food reward, delayed response for a 

fluid reward, and solution of a simple oddity problem, was unaffected by the 

weightless state. 

(4) Animals trained in the laboratory to perform during the simulated 

acceleration, noise, and vibration of launch and reentry were able to maintain performance throughout an actual flight. 

On the basis of the flight, Henry and his group drew the following conclusions : 

(1) The numerous objectives of the Mercury animal test program were met. 

The MR-2 and MA- ) tests preceded the first ·ballistic and orbital manned 

flights, respectively, and provided valuable training in countdown procedures 

and range monitoring and recovery· techniques. The bioinstru­mentation was 

effectively tested and the adequacy of the environmental control system was 

demonstrated. 
130 SPACE MEDICINE IN PROJECT MERCURY 

(2) A 7-minute (MR-2) and a 3-hour (MA-5) exposure to the weightless 

state were experienced by the subjects in the context of an experimental 

design which left visual and tactile references unimpaired. There was no 

significant change in the animal's physiological state or performance as 

measured during a series of tasks of graded motivation and difficulty. 

(3) The results met program objectives by answering questions concerning 

the physical and mental demands that the astronauts would encounter during 

space flight and by showing that these demands would not be excessive. 

(4) An incidental gain from the program was the demonstration that 

the young chimpanzee can be trained to he a highly reliable subject for 

space-flight studies.7 

The experience gained from the two animal flights (MR-2 and 

MA-5) was, however, not the only source of information availa1ble on space flight. 

MEDICAL IMPLICATIONS OF THE COSMONAUT FLIGHTS 

On April 2·6, 1961, 2 weeks after the orbital flight of Gagarin, 

the Embassy of the Union of Soviet Socialist Republics in Washington, D.C., issued certain medical data about the mission.8 The 

release read in part : 

The time has come for the practical creation of extraterrestrial scientific 

stations . . . . They will be followed by manned flights to the moon and 

other planets of the solar system, the creation of manned interplanetary 

stations and the gradual conditioning of men to space flight.9 

According to the release, Gagarin felt "perfectly well" throughout the orbiting phase and also during the period of weightlessness. It was noted that measures had been taken to protect the 

spacecraft from the hazards of space radiation. 

To provide answers to the medicobiological problems posed by 

space flight, it was reported, Soviet scientists since 1951 had carried 

out experiments with flights of anim·als in rockets to altitudes. up 

to 450 kilometers ('approximately 280 miles). Later, artificial 

earth satellites were used for making biological experiments-for 

example, it was considered important to study with maximum 

accuracy the biological effects of cosmic radiation. As a result 

of experimentation, orbital flight below the radiation belts was 

found to be safe for organized representatives of the animal world. 

It was therefore concluded that manned flight could be undertaken 

without harm to the cosmonaut's health. 

The cosmonauts' training had included, among other subjects, 

orientation in space medicine. Also included were special training and tests in aircraft flights under conditions of weightlessness, 

training in a simulated spacecraft cabin and on a special training 
SPACE MEDICINE IN 1961-62 131 

machine, prolonged stay in a specially equipped soundproof chamber, centrifuge tests, and parachute jumps from aircraft. Cosmonauts had to be aJble to stand the state of weightlessness for as 

long as 40 seconds and to partake normally of liquid, semiliquid, 

and solid food during that time. They also had to be able to discharge such functions as writing, radio communication, and reading, and to maintain visual orientation in space. Physiological 

studies and special psychophysiological methods "permitted the 

selection of people best fitted to discharge the missions accurately 

and who had the most stable nerves-emotional health," according to the Soviet report of April26, 1961.. The future cosmonauts 

"systematically did physical exercises to raise the organisms' resistance to acceleration forces as well as other factors of the new 

medium," it was reported. From the group of cosmonauts thus 

trained, Gagarin had heen chosen to make the first orbital flight. 

From the foregoing description, it is apparent that the U.S.S.R. 

and the U.S.A. had approached the problem of selection and training of the astvonauts in much the same manner, following the 

traditional methods of selection and training of pilots. The main 

difference in the biological-medical procedures had been that the 

U.S.S.R. had carried out more extensive animal experimentation 

than had the United States. 

A major difference in the approach, however, had been in the 

development of the life-support systems of the spacecraft. For 

Gagarin's flight the air-conditioning system maintained normal 

pressure and normal oxygen concentration in the pilot's cabin. 

The concentration of carbon dioxide did not exceed 1 percent. The 

temperature ranged from 15° to 22° C and the relative humidity 

from 30 to 70 percent. The air was regenerated chemically, and 

the heat in the pilot's cabin was absorbed by a liquid cooling agent. 

Gagarin wore a protective space suit. 

The journal M editsimkiy Rabotnik (Medical Worker) reported 

that Gagarin ate solid, pastelike, and liquid food during the flight. 

His menu was designed to avoid both overcharging the digestive 

system and accumulating excessive cellular tissue. He had no 

difficulty eating in the condition of weightlessness. Prior to flight 

he had tested foods prepared for consumption in flight and had 

chosen his favorites. "It is important," wrote G. F. Arutyunov 

(Master of Science in Medicine), "to have all the constituents 

of the food ration assimilated by the organism to the utmost." 10 

The major problem with which the Russians had wrestled prior 

to manned orbital flight was that of reentry. In August 1958 
132 SPACE MEDICINE IN PROJECT MERCURY 

they had sent two dogs on a ballistic flight to an altitude of 280 

miles with successful recovery by ejection of the dog containers 

during the descent. Subsequent development and testing led to 

the system used by Gagarin, which included a descent phase lasting 

approximately 30 minutes. In case the braking engine failed, the 

ship was designed to take advantage of atmospheric drag. The 

cosmonaut would make a landing on dry land, as contrasted with 

the Mercury landings on waterY 

On August 6, 1961, after Grissom's suborbital flight in July, 

the U.S.S.R. launched Cosmonaut Gherman S. Titov into orbit in 

a spacecraft (Vostok II) weighing 13 pounds more than Vostok I, 

launched the previous April. -(On the same date the report of the 

Space Science Board of the National Academy of Sciences was released; it recommended exploration of the moon and planets as the 

official goal of the U.S. space program.) The following day, 

August 7, it was reported from Moscow that Major Titov had successfully landed in Vostok II after 17 orbits in 25 hours 18 minutes. This was the first manned flight of more than one orbit, 

and the first test of man's reaction to prolonged weightlessness.12 

Other medical information would be forthcoming shortly. 

TOWARD GEMINI AND APOLLO 

Concurrent plans and objectives for space exploration brought 

the life sciences into an increasingly important-role as the Mercury 

Space Task Group prepared for the next operational step. The 

long-range obligations of space exploration enunciated by the 

President meant that not only must Mercury be successfully completed but Gemini and Apollo now must be planned for. 

All was not well, however, in the minds of the Nation's life 

scientists, despite the obvious success of the two U.S. suborbital 

flights and the U.S.S.R. orb~tal flight. The international scientific community had become increasingly concerned about reports-unverified at first, and then confirmed-that Titov had 

suffered motion sickness while in orbit. Did this mean that there 

were hazards of weightlessness or of combined stresses that should 

be investigated-before further plans were made to orbit a U.S. man 

in space~ The matter was of grave concern to the U.S. life 

scientists, aware that their first projected orbital flight was but 

a few months away. 

Also still unresolved was the total complex of problems that 

had bothered the life scientists since 1958 when Project Mercury 
SPACE MEDICINE IN 19G1-62 133 

was established. As Dr. White had reported, early work had 

been undertaken to extend man's tolerance to the biomedical rigors 

calculated to be inherent in the early flightsY Although technology would sustain life-support systems, there still remained serious 

problems about man's ability to meet the individual stresses which 

could not be reproduced on the ground (weightlessness and radiation) and the effect of the stresses on the body systems. The latter was complicated by the lack of knowledge of the impact of 

increasing time exposure. According to White: 

. . . proposed as a serious area for study was the composite effect of : the 

psychological effects of flight; the accelerations and vibrations of powered 

flight; the abrupt shift to the weightless environment with its inherent 

requirement for the adjustment of the physiological systems to the new 

baseline, later a reversal of these orbital patterns back to an entry program 

of acceleration, vibration, oscillation, and heating; and the landing impacts. 

This composite effect was a highly suspect one which would challenge man's 

survivability in space flight.14 

Now, on the eve of the first U.S. manned orbital flight, these 

questions of man's survivability in the light of these combined 

stresses were still unanswered. 

NOTES TO CHAPTER IX 

1 Proceedings of. a Conference on Results of the First U.S. Manned Suborbital Space Flight, NASA, June 6, 1961. 

2 For complete details, see Results of the Second U.S. Manned Suborbital 

Space Flight, July 21, 1961, Manned Spacecraft Center, NASA. 

3 L. E. Stringly, "Countdown and Procedures for Project Mercury. Atlas-5 

Flight (Chimpanzee Subject) ; Final Technical Documentary Report." 

Aeromedical Res. Lab. Tech. Documentary Rep. 62-17, Holloman AFB, 1962. 

4 Aeronautical and Astronautical Events of 1961, Report of the National 

Aeronautics and Space Administration to the Committee on Science and 

Astronautics, U.S. House of Representatives, 87th Congress, 2d sess., June 

7, 1962, p. 68. 

; Based on classified documents and off-the-record discussions by the 

author. 

6 Frederick H. Robles, Jr., Marvin E. Grunzke, and Herbert H. Reynolds, 

"Performance Aspects of the MA-5 Flight," ch. 9 in Results of the Project 

Mercury Ballistic and Orbital Chimpanzee Flights, NASA SP-39, 1963. 

7 James P. Henry, "Synopsis of the Results of the MR-2 and MA-5 

Flights," ch. 1 in Results of the Project Mercury Ballistic and Orbital Chimpanzee Flights, NASA SP-39, 1963. 

8 Press Release No. 109, Embassy of the Union of Soviet Socialist Republics, Apr. 26, 1961. 

9 Ib·id. 

10 As cited, ibid. 
134 SPACE MEDICINE IN PROJECT MERCURY 

11 Ibid. See also D. I. Fryer, "The Medical Sciences and Space Flight," 

R.A.E. News, Feb. 1964. 

12 Aeronautical and Astronautical Events of 1961, op. cit., p. 38. 

1:1 See ch. VIII, note 3. 

14 Ibid. 










































Phoenix Thomas R. A. DaviS, Civilian M.D.--spoillalty researcb In 

lsland. M.D. Ft. Knox. environmental physiology, 

experienced in public health, 

formerly at USAF Arctic 

Aero-Med Laboratory, surgical traln!nJl. 

Capt. Cba°les Wilson, Harvard .......... FUKht surgeon, a vifitlon medlUSAF, or USN or olne resldeo.t WADO stres

 

USPJIS liS alter- research, Man Hlgb monitor. 

nate. 

Hawlltl ....... Maj. Harry Bratt, BMD-Edwards ... Flight surgeon, bo.ard certtftUSAF. cate In a viatlon medicine, 

W ADC rxarcb. 

Capt. Wm. 13ltmch- Aero-Mad Lnb., Flight surgeon, bourd certillard. WADC. ǣ'l

to In avintlon medicine. 

West CoBst PedOc MlssUǨ R'Oollge Point Mugu, Nnvy Olght surgeon, R&D 

u.s. Staff (Capt. Pruett, CallL expe°lenoe. 

USN). 

llMD-Edwurds StaJf. Edwnrds AFD, X-15 flight surgeon, pilot, 

Calli. R&D monitor experience. 

Baja Cali· USAF School ot 

Aviatlon Medicine

. Lt. Col, David 

Simons,' USAF. 

USAF Scboolor 

Aviation Mcdiclne 

Staff, Capt. 

Hawkins, USAF. 

Brooke Army 

Hospital. 

Not dectl,loo;L...-----

Brooks AFB, FJlgllt surgeon, honrds in tW!B· 

rornln. , Tax. tlon medicine, Mal\ Hlgb 

pilot and project officer . 

Corvus BrooksAFJ;l, Flight surgoou, boards in avlaObristl. Tex. tlon medlci.n.a, resuarohcr in 

physiology, spaoo OlgbǤ. 

Sao Antonio, ne, 

Tex. 

Orand --

Bahama 

-·-·-·4 __ ., .................. _

bo considured a crllicnl staIsland. tion. Would be Important 

Orand Turk during reentry. WIUcon· 

Island. sldcr lilastbillty of manning 

!'rom Ospe. 

Mld-Atiantlc 1 2 USN personnel, l"cnsacoia NAB... Navy lliglltsurgeoo with R&D 

Ship. Comw. Frank oxper

tb

ow

bt

n

l

g

lo

Anstln, USN. w

kn

perso

C!Ulary Maj. Julian Ward, USAF, Europ&.... Fli

lslnods. USAF, t

and 

Mediolne researcb. 

Nlgorta....... Col. V anoo March· SAC-Loriug Senior flight surgeon. expert in 

banks, USAF. AFD, Lime· flight stros

, on ll-.>2 

stone, M.sine. uro�-tnd tbe world snd over 

the pole Olghts. Background would llS

!St U.S. 

presttge ln Nlgc.rla. 

'J'anganylka ..- Maj. John Lawson, Ft. Rucker, Ala... FllǦht ǧurgcon, speeinliat In inUSA. ternai medlelne, training in 

physiology research, M. 

PublieHealtb, Tropical 

Medldne. Dnckground 

would be w;efulln station 

and local reoovery. 

Bpeciallsǥ in internal me<llol

Surglellllesearr.ll Unit. 

On& or .mother of those may

naval avia tor 

suit tes& experien<le, 

s several astronauts 

naTiy, tt'St pUot. 

. boards In a viamedicine, dlsooverer 

Sobool or A vintion 

sclebt, 

StaUon NB!De Locatt\n Background & Con:unan_ts 

I 

\ 

APPENDIX 177 

l




Index 


A Aerospace Medical Laboratory, 53, 


58, 105, 118-119 


Abbott, Ira H., 173 
 Unusual Environments Section, 


Able,28,29 
 118 


Acceleraticn, 3, 11-12, 26, 32, 55, 60, 
 Veterinary Services Branch, 119 


62, 65, 67, 71, 77, 119, 121, 131, 
 Aerospace medicine, IX, 10, 34 


133,146,148-150,152 
 AF-NRC Committee on Bioastronau­


Accelerometers, 12 
 tics, 116 


Acoustics, 16 
 Air Force. See U.S. Air Force. 


Ad hoc committee. See Stever Com­
 Air Lubricated Free Altitude 


mittee. 
 (ALFA) trainer, 78 


Adjustment failures, psychological, 
 Air Rescue Service, 103 


33 
 Air Research and Development Com­


Advanced Research Projects Agency 
 mand (ARDC), 6, 15, 24--25, 48, 


(ARPA), 6, 7, 22,25-,-27, 173,174 
 53, 57, 85, 172, 178 


Advisory Committee on Man in 
 Liaison Office, Europe, 178 


Space, 6 
 Aircraft 


Advisory committees, 38 
 conventional, IX, 36 


Aerobee rockets; 18, 32 
 fighter, 14 


Aerodynamics research, Project Mer­
 high-speed, 14, 67, 77 


cury,23 
 jet, 47 


Aero-Medical Consultant Sta1f, 30 
 research, 1 
 Aeromedical Field Laboratory, 101­

transport, 14 
 102 


AiResearch Manufacturing Division, 
 Aero Medical Laboratory, USAF, 13, 


Garrett Corp., 73 
 25,48,54,66,115,119 


Aeromedical research, 11, 36 
 Alabama, 26, 177 


Aeromedical Research Laboratory, 
 Alberti, 17 


118 
 Albert II, 17 


Aeromedical team, 26, 28-29, 45, 90, 
 "Albert" capsule, 18 


118,120,123 
 Albuquerque, N. Mex., 48 


Aeromedicine, military, 36,37 
 Altltudes,10,12-15,17,18 


Aeronautical engineering, IX, 13 
 Ames Laboratory, 65 


Aeronautical research, 1, 2 
 Amick, Dr. L. D., 50 


Aeronautical and Space Sciences 
 Andel"80'11, Dr. Frank W., Jr., VI 


Committee, U.S. Senate, 33, 38- · 
 Anderson, Orvil A., 15 


39,113 
 Andrews Air Force-Base, 175 


.772--170 Q--..66.--13 183