Primate Space Flight Research

Table of Contents

Introduction

Purpose and Objectives of Primates in Space Flight Research

Selection and Training of Primates
---Selection
---Training

Animal Couch and Psychomotor Panel
---Animal Couch
---Psychomotor Panel

The Behavioral Tests

Pre-Mercury Primate Flights
---Albert 1
---Albert 2
---Aerobee 1
---Aerobee 2
---Aerobee 3
---Bioflight One
---Bioflight Two

Mercury Primate Flights
---Sam
---Miss Sam
---Ham
---Enos

Summary

References

Introduction

In the late 18th Century, man made one of his first attempts to reach the stars. In this attempt, a balloon carrying a duck, a rooster, and a sheep was used. Over the years the methods of reaching space have changed but the use of animals to test these new advances continues. When man made the breakthrough in technology that would finally enable them to reach space, the use of animals became extremely important. Before man could be sent into space it had to be proven that they could survive the trip and be able to function in the space environment. These animals were used to monitor the physiological parameters of the flights. In Russia, the scientists there chose to use dogs, while in the United States scientists chose to use primates in their test. During these tests, different species of primates where used. Chimpanzees were used for those flights that were done before humans were lunched into space. These animals that were used in the testing of spacecraft that would launch the first humans into space became some of the best-known animals in history.

Purpose and Objectives of Primates in Space Flight Research

The use of primates in space flight research began in the late 1940’s after World War II. The purpose of the test using primates was to determine if it was possible for living creatures to survive and function in the space environment. The first tests involving primates in space flight used them primarily to study the physiological effects of space on biological payloads. These early flights studied the effects that weightlessness, cosmic radiation, and high acceleration had on the animals. These tests were the first step in determining if it was possible for man to survive and work in space.

In 1958, when the National Aeronautical and Space Administration (NASA) was formed and the plans for Project Mercury were started, the use of primates became even more important, but the focus was shifted. “The intention was not to make extensive physiological studies of the effects of the weightless state, but rather to use animals to ensure the adequacy of the life-support systems” (Chimpanzee Flights, p.3). Primates were used more to test the equipment that would be needed and used to send man into space, than to test the effects of space on the health of living creatures.

In April of 1959, Project Mercury’s animal test program was started. Four main objectives were outlined for the program. These objective were:

(1) Provision of animal verification of a successful space flight prior to manned flight.

(2) Provision of data on the physical and psychological demands which were to be encountered by the astronauts during space flight.

(3) Provision of a dynamic test of operational procedures and training of support personnel in handling the biomedical program for manned flight.

(4) Evaluation of the Provision spacecraft environmental control system and bioinstrumentation under flight conditions. (Chimpanzee Flights, p.1) With these objectives in place, the animal test program was ready to begin in the selection and training of the primates that would be used in the tests.

Selection and Training of Primates

After it was determined by the medical research tests that primates would be the animals of choice for the Mercury testing, they had to decide on the type of primates that would be used. For the first tests to be done, primates like cynomolgus, rhesus, cebus, and squirrel monkeys were used because of their small stature (Nonhuman Primates in Space, p.4). For the test flights that would be done before the human flights, chimpanzees were to be used. Chimpanzees were chosen because of their similarities to man in biology and because of their small stature. The training for the chimpanzees took place at the 6571st Aeromedical Research Laboratory at Holloman Air Force Base in New Mexico (Chimpanzee Flight, pp.3-4).

Selection

When selecting the primates that were to be used, the scientists looked for animals that were young, healthy, and in the case of the chimpanzees, mentally able to perform tests in space. The temperament of the primates was also considered. Temperament was important because if the animal was easily angered, they would be harder to train, and they would not be capable of undergoing the rigors of space flight. The primate would not be able to handle the long hours of being trapped in a small confined place with out hindering the results of the tests (Nonhuman Primates in Space, pp.197-98).

Training

The training that the primates went through varied depending on the type of flight that was to be made. The first primates that were used were not trained to perform any task during the flights. These animals were used to gain biomedical information on the effects that launch, space, re-entry, and recovery had on them physically (Nonhuman Primates in Space, p.4). Later, when chimpanzees were used for the tests, they were trained to perform various tasks during the flights. Before the chimpanzees were trained for their space flights, 35 veterinary technicians and 10 veterinary officers were given two weeks of training on how to handle them (Chimpanzee Flights, p.1-6).

Many of the chimpanzees underwent hundreds of hours of training for their possible space flight. During the training they were introduced to the couch that would be used to house them during the flights and the panel that would be installed for them to perform the behavioral tasks on. To help with the training the McDonnell Aircraft Company made six training couches (see Figure 1). Simulated flights were also preformed in the chimpanzees’ training. These simulations were run to determine the effects of acceleration and vibration on the chimpanzees and acclimate them to flight conditions. The simulated flights were also used to evaluate the couch system and panel (Chimpanzee Flights, pp.4, 21, & 39).

Figure 1: Ham in Training Couch (WWW1)

Animal Couch and Psychomotor Panel

When the time came to test the space capsule’s life support systems and task performance ability in space, NASA needed a special animal couch to both house the chimpanzees and the device that would be used to test performance. The task of building the animal couch went to the McDonnell Aircraft Company (Chimpanzee Flights, p.4).

Animal Couch

The couches that were used prior to the chimpanzee flights were only used to restrain and protect the animal during flight. These couches were designed around the animal that would be used. For the chimpanzee flights, the couch was used for more then just animal restraint and safety. The couch was used to test the environmental control loop in the Mercury capsule that the astronauts’ pressure suits would use. The couch had the same hookup system to the control loop as the pressure suits and had a cover that could be sealed to simulate the pressure suit with the faceplate closed. The couch fit both the chimpanzee and the psychomotor panels inside, did not interfere with the Mercury spacecraft interior, and only require enough power from the spacecraft systems for its operation. The couch was designed to fit any of the chimpanzees that could have been chosen to fly and had restraints built into it. The same couch design was used by both the ballistic and orbital flights with only a change in the psychomotor panel (Chimpanzee Flights, pp.15-19).

Figure 2: Animal Couch Capsule (Chimpanzee Flight)

Psychomotor Panel

The panel for the ballistic flight consisted of three lights (blue, white, and red), and two levers (see Figure 3). The panel was programmed to present two shock-avoidance programs. To deliver the shocks, the panel was also connected to the primate through a shocking mechanism on their feet. Timer and stepper switches were used. The timer and stepper switches were modified from commercial products (Chimpanzee Flights, pp.15-19).

Figure 3: Ballistic Flight Panel (WWW1)

The panel for the orbital flights consisted of three levers instead of two, and in place of different colored lights the panel had lighted symbols. The orbital panel also had a pellet dispenser to deliver banana-flavored pellets to the chimpanzee (see Figure

4). Like the ballistic panel, the panel for the orbital missions was also connected to the chimpanzee so that it was able to deliver mild shocks to the animal’s feet (Chimpanzee Flights, pp.15-19).

Figure 4: Orbital Flight Panel (Chimpanzee Flight)

The Behavioral Tests

For the first chimpanzee flight, these task involved pressing on a lever at certain specified times to either stop an electrical shock, or to prevent an electrical shock from happening. For the second chimpanzee flight, the same tasks of stopping or avoiding electrical shocks was the same, but the add task of obtaining food and water were added (Chimpanzee Flights pp.15-19, 21-23, 39-51).

In order to perform the behavioral tasks, the chimpanzees were trained to press a certain lever when a certain light on the panel was lighted. The color of the light dictated which lever to press. In turn, this would stop the shock they the chimpanzee was experiencing, or prevent it from receiving the shock, or it would allow the animal to retrieve food pellets or water in the case of the orbital flights. These tasks would be performed throughout the flights. The times for each task were random so that the chimpanzees did not learn a pattern to follow, but rather learn the correct action for a specific stimulus. This was to judge the animal’s reaction time to determine whether stresses that may be encountered before and during flight would affect in-flight performance (Chimpanzee Flights, pp 15-19, 21-23, 39-51).

Pre-Mercury Primate Flights

Before Project Mercury was established in 1958, primates had been used by the United States Air Force and Navy to study the effects of space. The types of monkeys that were used were cynomolgus, rhesus, cebus, and squirrel. These monkeys that were used were also anesthetized. A team of Air Force investigators lead by Dr. James P. Henry did some of these first tests. During these flights they obtained information on physiological effects like pulse and respiration rates, and arterial and central venous pressures. These early flights were important to the success of the Mercury Program (Nonhuman Primates in Space, p.3)

Albert 1 Launched: June 18, 1948

Albert was a rhesus monkey that weighted 4.0 kg. He was housed in a capsule located in the nose cone of the rocket. Albert died before take off due to a failure in the life support system. The flight was launched any way but never recovered because of parachute failure. Even with the death of Albert and the failed recovery the mission still proved that a capsule capable of carrying a small primate was constructed, a biological payload was successfully launched, and that physiological information could be sent back (Nonhuman Primates in Space, p.4)

Albert 2 Launched: June 14, 1949

Albert 2 was also a rhesus monkey. He was launched to an altitude of 134 km (83 miles). Respiration and electrocardiograms were recorded during this flight. Like the launch of Albert 1, parachutes failed to deploy and Albert 2 died on impact (Nonhuman Primates in Space, p.4).

Aerobee 1 Launched: April 1951

The monkey on board was a cebus. The monkey’s ECG and respiration were measured. The monkey was not recovered due to parachute failure (Nonhuman Primate in Space, p.5).

Aerobee 2 Launched: September 20, 1951

This was the first totally successful rocket flight. The monkey on board the flight was a rhesus, which went to an altitude of 70,800m (236,000ft). During the flight, ECG, respiration, and arterial and central venous pressure were measured. The monkey landed safely in a desert, but due to a delay in the recovery, he died of heat exposure on the way to the base (Nonhuman Primates in Space, p.5).

Aerobee 3 Launched: May 21, 1952

On this flight two cebus monkeys, Mike and Patricia, were used. Each was placed in different positions to receive different G loads. Mike was placed to receive +Gz, and Patricia was placed to receive +Gx. ECG’s during the flight were obtained, but arterial and venous pressure measure attempts failed. Both Patricia and Mike survived the flight and landing. Patricia did die two years after the flight because of a bite that got infected when fighting with Mike. Mike lived a long life and had offspring. Aerobee 3 was the last flight in that series (Nonhuman Primates in Space, p.5).

Bioflight One Launched: December 13, 1958

The primate on this flight was a 0.5kg squirrel monkey named Gordo a.k.a “Old Reliable” (see Figure 5). Gordo was the first anaesthetized monkey to travel in the nose cone of a ballistic missile, a Jupiter rocket. He traveled to an altitude of 483km (300mi) and down range a distance of 2,093km (1300mi). During the flight heart rate, heart sounds, respiration rate, body temperature, cabin temperature and pressure, and radiation were measured. Telemetry found that Gordo survived up to 10 G’s of acceleration during accent and up to 40 G’s on reentry. Gordo’s flight indicated that man could tolerate similar conditions. Gordo was not recovered due to a nose cone flotation failure (Nonhuman Primates in Space, p.6)

Figure 5: Gordo (WWW1)

Bio Flight Two Launched: May 28, 1959

This flight had two primates on board. Able was a 3.2kg rhesus monkey, and was placed in the nose cone of the Jupiter rocket three days prior to flight. Baker was a 0.5kg squirrel monkey, and was place inside the rocket six hours prior to launch. During the flight, the same things were recorded as Bioflight One plus electromyograms (EMG’s) were measured. Able was trained to tap a telegraph key every time a red light flashed, but before take off the tester quit transmitting. This was to have been the first in-flight performance test. Both monkeys survived the flight and were recovered. Able died five days after the flight from anesthesia to remove electrodes. Baker lived for many years after the flight and had offspring. Able and Baker’s flight was so normal that Baker appeared to doze or become drowsy for the middle part of the flight (Nonhuman Primates in Space, p.6).

Figure 6: Able & Baker (WWW1)

Mercury Primate Flights

In 1958, Project Mercury was formed. NASA planned to use primates to continue testing the effects of high acceleration and space environment on biological organisms, and later to test the space capsules’ viability for manned flight.

Sam

Sam was the first official primate to be launched in the Mercury Program. He was a rhesus monkey that weighted 3.6kg. Sam was launched to an altitude of 84,000m (280,000ft) on a Little Joe rocket. The flight was to evaluate biomedical effects of acceleration experienced during the abort of a Mercury flight after lift off. Sam survived, and did the first successfully recorded performance test. The test was the same as the one Able was trained to perform.

Figure 7: Sam (WWW1)

Miss Sam Launched: January 21, 1960

Miss Sam was a female rhesus monkey that weighted 2.7kg. She was launched to an altitude of 14,700m (49,000ft) on a Little Joe rocket. The same effects that were studied during Sam’s flight were studied during Miss Sam’s flight. Miss Sam was also trained to perform the same task as Able and Sam. Her performance was not as good as Sam’s performance. She and the capsule were successfully recovered (Nonhuman Primates in Space, p.6)

Ham Launched: January 31, 1961

This was the first launch with a chimpanzee. The flight was launched to an altitude of 251 km (156 mi), a range of 667 km (414 mi), and reached speeds of 9340 kmph (5800 mph). This flight preceded the flight of Commander Allen Sheppard, the first American in space. The same type of capsule and rocket that was going to be used for Sheppard’s flight was used in the flight of Ham. Ham was a 16.7 kg (37 lb) male chimpanzee. His age was approximately 44 months. He was chosen two days prior to the launch of the mission. He was one of six possible candidates. By this point, Ham had undergone 219 hours of training in a 15-month period and had multiple physical examinations. During his ballistic flight he experienced seven minutes of weightlessness, and performed the psychomotor test. His respiration, temperature, and ECG monitored during the mission. Ham’s flight proved that an animal that closely resembled man could survive the stress of sub orbital flight and perform tasks that were required throughout the flight. Ham survived the flight with no problems, but was found to not like the capsule any more and was no longer useful in space flight missions (Nonhuman Primates in Space, p.7 & Chimpanzee Flights, pp.35-38)

Figure 8: Ham During an Exam (WWW1)

Enos Launched: November 29, 1961

Enos was a male chimpanzee that was used to test the Mercury capsule and Atlas rocket that would be used to send astronaut John Glen into the first manned American orbital flight. Enos weighted 18.9 kg (42 lb) and was 63 months old. By the time that he undertook his orbital flight, he had 1,263 hours of training over 16-month period. Of the 1,263 hours of training, 343 hours were under restraint conditions in the lab model of the couch used during flight. Enos spent approximately three hours in weightlessness. During his time in space he performed many of the same tasks that Ham did on his flight, along with a eating and drinking in space. Many of the same things that were monitored during Ham’s flight were monitored in Enos’ orbital flight. Enos was successfully recovered. He died on November 4, 1962 about one year after his flight at Holloman Air Force Base. His had been ill for two months with Shigella dysentery (Nonhuman Primates in Space, p.7 & Chimpanzee Flights, pp.39-51).

Figure 9: Enos (WWW1)

Summary

Primates hold a significant position in the history of American space flight. The physiological experiments and high-risk flights that the primates endured allow man to travel into space safely. When thinking of Allen Sheppard, John Glen, and the other Mercury Seven astronauts, one should also remember the names of Gordo, Able and Baker, Ham, and Enos, because with out them the manned flights into space would not had happened.

References

Sandler, Harold (1977). A review of animal flight experiments. (pp. 3-21). In Geoffrey H. Bourne & Richard C. Simmonds (Eds.), NASA conference publication 005 The use of nonhuman primates in space: Proceedings of a symposium at Ames Research Center Moffett Field, California December 2-4, 1974. Springfield, VA: National Technical Information Service.

Henry, James P. M.D., Ph.D. & John D. Mosely D.V.M. (Eds.). (1963). Results of the Project Mercury ballistic and orbital chimpanzee flights. Washington, DC: Office of Scientific and Technical Information National Aeronautical and Space Administration.

Mercury. (24 April 2003)
Available: http://www-pao.ksc.nasa.gov/ kscpoa/history/mercury.
Retrieved 15 January 2004

Research and development phase of Project Mercury. (n.d.).
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Retrieved 15 January 2004

WWW1 Famous monkeys through history. (n.d.).
Available: http://www.ape-o-nut.org/ famous/reallife.html.
Retrieved 25 February 2004