By the spring of 1959 it had become apparent that as the design and construction of the manned spacecraft proceeded, considerable coordination of Space Task Group effort would be required to monitor the McDonnell contract adequately. A Capsule Coordination Office and Capsule Review Board were established by STG. These lield frequent meetings at the management level.18
A mockup spacecraft had been completed by March 1959. The Mockup Board recommended no major changes except in the cockpit area, and it was further recommended that these changes await the selection and initial orientation of the Mercury astronauts.
Between May and August 1959, the astronauts gave considerable attention to the cockpit area, as did other NASA personnel. Among the factors considered were:
1. The operational procedures which the astronaut must follow during routine and emergency flight.
2. The anthropometric dimensions of the seven astronauts, which demonstrated several additional inadequacies in the placement of switches and controls of the earlier layout.
3. Studies of the dimensions of the astronauts while wearing a full-pressure garment, in both the routine unpressurized state and the pressurized state. These factors provided the basis for the spatial and geographic layout within the spacecraft so the astronauts could reach any control under both routine and emergency conditions. This layout, when correlated with the visual fields of the astronauts, demonstrated additional limitations of the initial layout.19 Several cockpit changes were made on the basis of this information, all of which would be effective for all the manned orbital flights and for all the manned ballistic flights except the first.
Other design studies which would directly affect the comfort and safety of the astronaut included egress studies that resulted in a quick-release side door for rapid access to the astronaut and for emergency exit.
Although many minor changes were made in spacecraft equipment, only a few major changes were necessary. For example, the originally specified extended-skirt main parachute for landing was found to be unsafe for operation at altitudes above 10,000 feet, and was replaced by a similar size "ring sail" parachute. In June 1959, considerations of parachute loads and deployment during large oscillations or tumbling of the parachute led to the elimination, and then reinstallation, of the drogue parachute. Finally, the initial concept of an impact bag was eliminated, only to be reinstated because of the hazards of wind-induced loads and the possibility of land impacts after early aborts.
In the fall of 1959 the astronauts spent a period of indoctrination at the Navy Air Crew Equipment Laboratory, Philadelphia. Their activities included:
1. Initial dressing, fitting, and routine ground-level pressurization of the individual suits
2. Altitude-chamber runs consisting of 1 hour in unpressurized suit with chamber at 5 psia, pure oxygen, and 1 hour in chamber pressurized to 1 psia with suit at 4.75 psia,
3. Simulated reentry with temperature, pressure, and ventilation of normal Mercury reentry and landing
4. Work-space orientation using Mercury console mockup (referred to in the previous section)
The principal difficulty thus far encountered in the indoctrination
program appeared to be that of obtaining the proper suit fit for each astronaut.
L. N. McMillion, of the Space Task Group, reported in November 1959 that
four of the astronauts had thus far participated in the indoctrination.
Throughout the Mercury project a continuing developmental program was conducted to utilized the latest technological advances compatible with the constraints imposed by the spacecraft configuration and mission. This include, for example, such features as glove lights to illuminate the instrument panel, a urine collection and transfer system, improved shoulder construction of the suits to provide increased upper-torso mobility, and a mechanical visor seal.21
NASA was able to draw upon the resources of the Air Force, the Navy, industry, and academic and private research institutions to develop life-support systems to protect man against the stresses of launch, orbit, reentry, and impact. As has already been noted, in April 1958 Maxime A. Faget, had suggested the idea of a contour couch to withstand the high g-loads imposed by acceleration and reentry forces of manned space flight, and such a couch was subsequently developed for the Mercury astronauts. It should, in addition, be emphasized that since World War II extensive research had been carried out for the Air Force and Navy by the services, by industry, and by academic and private research institutions.22 Particular mention should also be made of the concurrent work by C. F. Gell, H. N. Hunter, P. W. Garland, and others at the Naval Research Laboratory, and by J. P. Stapp, S. Boudurant, N. P. Clarke, W. G. Blanchard, H. Miller, R. R. Hessberg, E. P. Hiatt, Eli Beeding, and others in the services.23 The literature in the field was extensive and experimentation applicable to high-speed flight, was going steadily forward, particularly with the X-15.24
In the fall of 1959, the seven astronauts began intensive testing of their life-support systems as well as intensive training and indoctrination in the use of life-support systems. Part of this testing and indoctrination was accomplished on the centrifuge at the AMAL in Johnsville. Three programs were carried out, one each in August 1959, April 1960, and October 1960. The program held October 3-14, 1960 is described in some detail because this was the period in which the Life Systems Division of STG not only evaluated the astronautsí personal equipment such as harness, couch, and pressure suit, but also evaluated the effectiveness of the bioinstrument, sensors for monitoring of biomedical data during actual flights (discussed in the following chapter). The objectives of the program were "to train the astronauts for the Mercury-Redstone mission, and to obtain basic medical data to be used to monitor the astronauts' well-being during flights."25 This was 6 months before the Shepard flight.
The astronauts followed as closely as possible the procedures that would be used for the actual mission. To illustrate the kind of teamwork required, the detailed assignments of the STG group are described below. Dr. C. P. Laughlin would record, process, analyze the physiological stress information about the astronauts including pre- and post-training physical examination; monitoring and tabulation of pulse, respiratory rate, body temperature and electrocardiogram pre- and post-training vital capacity; pre- and post-training nude weight; and pre- and post-training volume and specific gravity of urine. The major part of the physiological stress information would be gathered by personnel of the National Institutes of Health and Dr. J. P. Henry of STG. Fluid loss and vital capacity measurements would be under the direction of Dr. William S. Augerson. Insertion of the astronauts into the spacecraft would be done by one of two teams: Dr. William K. Douglas and Joe W. Schmitt, or Dr. C. B. Jackson and Harry D. Stewart. Drs. Douglas, and Jackson would also evaluate the effectiveness of t the. biosensor performance. The pressure suit and urine bag would be evaluated by Lee N. McMillion. William H. Bush would be responsible for the electronic part of the biomedical recording, and Morton Schler would be responsible for procurement, installation, and monitoring of the environmental control system. The couch and restraint harness would be evaluated by Gerard J. Pesman.26
Most of the astronauts considered their couches "reasonably comfortable." As a result of earlier studies which indicated that the astronaut needed to be able to release his harness more quickly, minor modifications were made so that the harness could be released in four simple movements.
The reliability of the components of the Mercury environmental control system (ECS) was "completely satisfactory."
The astronauts' pressure suits, which had been delivered in September,
received their first intensive use in this period. The leakage rates for
the new suits ranged from 80 to 300 cc/min, small rates compared with those
of previous suits. The bioinstrumentation connector was a modified Bendix
plug attached on top of the right thigh of each suit. The new connector
was reliable and a definite improvement over the snap patch previously
used. The latching device for securing the inside connector to the suit
"operated with some difficulty," although it was believed the suit would
be accept able for operational use. Meanwhile, B. F. Goodrich Co. would
continued to investigate improved latching methods.27
Still another concern for the Life Systems Division had been the establishment of procedures and timing for astronaut insertion into the spacecraft as well as for postflight debriefing. It was concluded that although insertion techniques presented no major problems, insertion procedures should be practiced and should be conducted with it properly itemized checklist.
The October 1960 program had as one of its objectives the obtaining of basic medical data to be used to monitor the astronautís well-being during flights. During the program simultaneous measurements were made of the emotional state, metabolism of adrenal medullary and cortical hormones, and control performance during the training program. Blood and urine samples were taken before and after repeated exposure to acceleration.
This program was directed by Dr. G. E. Ruff of the University of Pennsylvania (who, during his tour of duty with the Air Force, had participated in the astronaut-selection stress tests at WADC). Urine samples were analyzed at the National Institutes of Health, Bethesda, Md., and blood samples by Dr. Kristen Eik-Nes, University of Utah. Dr. Ruff also interviewed all the astronauts at least once. All the astronauts took simple pencil and paper tests for evaluation of their emotional state.28
Through the remaining months before the Shepard flight, the astronauts
would continue their intensive training pace at Langley and at Cape Canaveral.
Up to the last moment, advances in technology would be incorporated into
the life-support systems to the degree possible under the constraints imposed.
18. This section Is based on Purser, Memo for Chief, op. cit.
19. Ibid., P. 3.
20. L. N. McMillion, Life Systems Br., Memo for Chief, Flight Systems Div., Subj.: Trip Report, Nov. 20, 1959.
21. Richard Johnston, Edward L. Hayes, and Lawrence F. Dietlien, "Crew Systems Development In Support of Manned Space Flight," an undated manuscript circa summer 1963.
22. The reader Is referred particularly to the following references: Ralph L, Christy, "Effects of Radial and Angular Accelerations," including 33 footnote references; John Paul Stapp, "Effects of Linear Acceleration," with 10 footnote references; Paul Webb, "Temperature Stresses," with 26 footnote references; James B. Nuttall, "Escape, Survival and Rescue," with 54 footnote references; Lawrence E. Lamb, "Cardiovascular Considerations," with 13 references, and Hubertus Strughold, "Space Medicine," all in Harry G. Armstrong. Aerospace Medicine (Baltimore: Williams & Wilkins, 1961). See also Human Acceleration Studies, Publication 913, NAB-NRC. This includes, an excellent bibliography by George Bates, a proposed physiological acceleration terminology with a "Historical Review" by Carl C. Clark and Richard J. Crosbie, and a discussion by Rufus R. Hessburg, "Acceleration Environments Pertinent to Aerospace Medical Research." See also Carl C. Clark and Dennis Faubert, "A Chronological Bibliography on the Biological Effects of impact," Martin Engineering Rep. 11953, Sept. 1961, and additions prepared by Dr. Clark as a result of the Symposium on Impact Acceleration Stress held under the auspices of the Man-in-Space Committee of the Space Science Board, National Academy of Sciences-National Research Council, at San Antonio, Tex., Nov. 27-29, 1961. See also Ashton Graybiel, "Significance of Vestibular Organs in Problems of Weightlessness"; R. Grandpierre and F. Violette, "Contribution à líÉtude des Effets de líApésanteur sur le Systeme Nerveux Central du Rat"; U. V. Parin and O. G. Gazenko. "Soviet Experiments Aimed at Investigating the Influence of Space Flight Factors on the Physiology of Animals and Man"; all in Livingston et al., Life Sciences and Space Research, op. cit.
23. See, for example, C. F. Gell and P. W. Gard, "Problem of Acceleration," Force NAVPERS 10839-A, Navy Dept., -1955. See also S. Bondurant, N. P. Clarke, et al., "Human Tolerance to Some of the Accelerations Anticipated In Space Flight," U.S. Armed Forces Med. J., vol. 9, no. 8, Aug. 1958, pp. 1093-1105.
24. The principal human centrifuges throughout the world Included those in the United States at the Mayo Clinic, Rochester, Minn.; Wright-Patterson AFB, Ohio; the University of Southern California; the Naval Air Station. Pensacola, Fla.; The Naval Air Development Center, Johnsville, Pa.; in Canada, the Canadian Air Force, Toronto; In England, the Royal Air Force, Parnborough; in France, the French Air Force, Brebtigny Flight Test Base: In Germany, the Institute of Aviation Medicine, Bad Nauheim; in Sweden, the Swedish Air Force, Stockholm; and in Japan. Others were under construction.
25. Augerson. Henry, et al., op. cit.
26. Ibid., p. 21.
27. Ibid., pp 7-9
28. Ibid., p. 7.