A second group of experiments sought to prove the workability of the escape system designs in shots at Wallops Island. On March 11 the first "pad abort," a full-scale escape-rocket test, ended in a disappointing failure. After a promising liftoff the Recruit tractor-rocket, jerking the boilerplate spacecraft skyward, suddenly nosed over, made two complete loops, and plunged into the surf.
So disappointing was this test that for several weeks the fin-stabilized pod rocket escape system was almost reinstituted.27 Three Langley engineers, [142] chagrined by this threat to their work, conducted a full postmortem following the recovery of the capsule. They blamed the erratic behavior on a graphite liner that had blown out of one of the three exhaust nozzles. Willard S. Blanchard, Jr., Sherwood Hoffman, and James R. Raper, working frantically for a month, were able to perfect and prove out their design of the escape rocket nozzles by mid-April. At the same time they improved the pitch-rate of the system by deliberately misaligning the pylon about one inch off the capsule's centerline.28
The third applied research program was a series of exhaustive wind-tunnel investigations at Langley and at the Ames Research Center to fill in data on previously unknown values in blunt-body stability at various speeds, altitudes, and angles of attack. Model Mercury capsules of all sizes, including some smaller than .22 rifle bullets, were tested for static-stability lift, drag, and pitch in tunnels. Larger models were put into free flight to determine dynamic-stability characteristics. Vibration and flutter tests were conducted also in tunnels. The variable location of the center of gravity was of critical interest here, as was also the shifting meta-center of buoyancy.29
Using the thunderous forced-draft wind tunnels at Langley and Ames, aeronautical research engineers pored over schlieren photographs of shock waves, windstreams, boundary layers, and vortexes. Most of the NASA tunnel scientists had long been airplane men, committed to "streamlined" thinking. Now that H. Julian Allen's blunt-body concept was to be used to bring a man back from 100 miles up and travelling about five miles per second, both thought and facilities had to be redirected toward making Mercury safe and stable.
Albin O. Pearson was one such airplane-tunnel investigator who was forced to change his way of thinking and his tools by the ever higher mach number research program for Mercury. Pearson worked at Langley coordinating all aerodynamic stability tests for Mercury with blunt models at trans-, super-, and hypersonic speeds. While exhausting the local facilities for his transonic static stability studies, Pearson arranged for Dennis F. Hasson, Steve Brown, Kenneth C. Weston, and other Langley, STG, and McDonnell aerodynamicists to use various Air Force tunnels at the Arnold Engineering Development Center, in Tullahoma, Tennessee. Beginning on April 9, 1959, a number of Mercury models and escape configurations were tested in the 16-foot propulsion wind tunnel and 40-inch (mach 22 capability) "Hot Shot" facility at Tullahoma. During the next 16 months a total of 103 investigations utilizing 28 different test facilities were made in the wind-tunnel program.30
A fourth experiment program concerned specifically the problem of landing impact. Ideally touchdown should occur at a speed of no more than 30 feet per second, but how to ensure this and how to guard against impacts in directions other than vertical were exasperating problems. Landing-loads tests in hydrodynamics laboratories for the alternative water landing had only begun. The anticipated possibility of a ground impact, which would be far more serious, demanded shock absorbers far better than any yet devised. Although there was [143] still no assurance that the astronaut inside a floating capsule could crawl out through the throat without its capsizing, this egress problem was less demanding at the moment than the need for some sort of crushable material to absorb the brunt of a landing on land.
Through April and May, McDonnell engineers fitted a series of four Yorkshire pigs into contour couches for impact landing tests of the crushable aluminum honeycomb energy-absorption system. These supine swine sustained acceleration peaks from 38 to 58 g before minor internal injuries were noted. The "pig drop" tests were quite impressive, both to McDonnell employees who left their desks and lathes to watch them and to STG engineers who studied the documentary movies. But, still more significant, seeing the pigs get up and walk away from their forced fall and stunning impact vastly increased the confidence of the newly chosen astronauts that they could do the same. The McDonnell report on these experiments concluded, "Since neither the acceleration rates nor shock pulse amplitudes applied to the specimens resulted in permanent or disabling damage, the honeycomb energy absorption system of these experiments is considered suitable for controlling the landing shock applied to the Mercury capsule pilot."31
Fifth, and finally, other parachute experiments for spacecraft descent were of major concern in the spring of 1959, because neither the drogue chute for stabilization nor the main landing parachute was yet qualified for its task in Project Mercury. Curiously, little research had been done on parachute behavior at extremely high altitudes. Around 70,000 feet, where the drogue chute was at first designed to open, and down to about 10,000 feet, where the main landing chute should deploy, tests had to be carried out to measure "snatch" forces, shock forces, and stability parameters. Some peculiar phenomena - called "squidding," "breathing," and "rebound" in the trade - were soon discovered about parachute behavior at high altitude and speed. In March, one bad failure of an extended-skirt cargo chute to open fully prompted a thorough review of the parachute development program. Specialists from the Air Force, Langley, McDonnell, and Radioplane, a division of the Northrop Corporation, met together in April and decided to abandon the extended-skirt chute in favor of a newly proved, yet so far highly reliable, 63-foot-diameter ringsail canopy. The size, deployment, and reliability of the drogue chute remained highly debatable while STG sought outside help to acquire other parachute test facilities.32 The status of most other major capsule systems was still flexible enough to accommodate knowledge and experience gained through ongoing tests.
Two other major problems on which Langley also worked with STG, while NASA Headquarters planned the role and functions of the new center in Beltsville, concerned the formulation of final landing and recovery procedures and the establishment of a worldwide tracking network. Mercury planners had assumed from the beginning that the Navy could play a primary role in locating and retrieving the capsule and its occupant after touchdown. But a parallel assumption that existing military and International Geophysical Year tracking [145] and communications facilities could be utilized with relatively slight modifications had to be overhauled in the light of a more thorough analysis of Mercury requirements.
The Navy's experience with search and rescue operations at sea could be trusted to apply directly without much modification to retrieval of the Mercury capsule. But a multitude of safeguards had to be incorporated in the capsule to ensure its safety during and immediately after impact and to reduce the time required for recovery to a bare minimum. William C. Muhly, STG's shop planner and scheduler, was most worried about these recovery aids for the Big Joe tests.33
The most serious technical decision affecting the landing and recovery procedures concerned the feasibility of using an impact bag to cushion the sudden stop at the surface of Earth. Gilruth liked the idea of using a crushable honeycomb of metal foil between the shield and the pressure vessel to act as the primary shock absorber. But a pneumatic bag, perhaps a large inner tube or a torus made of fabric and extending below the capsule, either with or without the heatshield as its base, was still appealing. Associated with the recovery problem [146] were innumerable other factors related to recovery operations. The seaworthiness of the capsule, its stability in a rough sea, the kinds of beacons and signaling devices to be used, and the provisions for the possibility of a dry landing were foremost among these worries.34
The second major area of uncertainty revealed in January 1959 came as something of a surprise to Task Group people. They had assumed that the world was fairly well covered with commercial, military, and scientific telecommunications networks that could be a basis for the Mercury tracking and communications grid. The Minitrack network established roughly north and south along the 75th meridian in the Western Hemisphere for Project Vanguard turned out to be practically inapplicable. On the other hand, the "Moonwatch" program and the optical tracking teams using Baker-Nunn cameras developed by the Smithsonian Institution Astrophysical Laboratory supplied invaluable data during 1958. Tracking of artificial satellites showed that all previous estimates of atmospheric density were on the low side.35
Trajectory studies for equatorial orbits showed a remarkable lack of radio and cable installations along the projected track. Much depended upon the precise trajectory selections and orbital calculations for a Mercury-Atlas combination. New Atlas guidance equations that would convert the ballistic missile into an orbital launch vehicle had been assigned to the mathematicians of Space Technology Laboratories (STL) in Los Angeles. But whatever these turned out to be, it was becoming apparent that the world was far less well-wired around the middle and underside than had been thought. Furthermore the medical teams were insisting on continuous voice contact with the pilot. So by the end of February, Charles W. Mathews had convinced Abe Silverstein that STG should be relieved of the monumental tracking job, and NASA Headquarters drafted another contingent of Langley men to set up a brand-new communications girdle around the world.36
A large part of the Instrument Research Division at Langley, under the directorship of Hartley A. Soulé, provided the manpower. Soulé had previously laid out a timetable of 18 months for completion of a tracking network. Now he and the Langley Procurement Officer, Sherwood L. Butler, undertook to manage the design and procurement of material for its construction.37 Ray W. Hooker accepted the supervision of the mechanical and architectural engineering, and G. Barry Graves began to direct the electronics engineering. By mid-March the problem of providing a tracking network for Mercury was on the shoulders of a special task unit that came to be known as the Tracking and Ground Instrumentation Unit, or by the barbarous acronym "TAGIU." Although by this time most of the other divisions at Langley were also acting partially in support of Mercury, the Tracking Unit held a special position in direct support of the Space Task Group. Indirectly it provided NASA with its first equatorial tracking web for all artificial satellites. Some 35 people in the unit went to work immediately on their biggest problem, described by Graves as "simply to decide what all had to be done."38 By the end of April, Soulé had seen the imperative [148] need for a high order of political as well as technical statesmanship to accomplish his task on time. A detailed report to Silverstein outlined his operational plans.39
On March 17 and 18, 1959, at the McDonnell plant in St. Louis, the manufacturers presented to the Space Task Group for its review, inspection, and approval the first full-scale mockup of the complete Project Mercury manned satellite capsule. This "Mockup Review Inspection" represented a rough dividing line between the design and development phases for the project. The "Detail Specifications," 80 pages in length, provided a program for the customers. Another McDonnell document provided a written description of the "crew station" procedures and capabilities. And the mockup itself showed the configuration "exploded" into seven component parts: adapter ring, retrorocket package, heatshield bottom, pressure bulkhead, airframe, antenna canister, and escape rocket pylon.40
The chief designers, constructors, and managers of the program gathered around the capsule to watch demonstrations of pilot entry, pilot mobility, accessibility of controls, pylon removal, adapter separation, and pilot escape. The board of inspection, chaired by Charles H. Zimmerman, then Chief of the Engineering and Contract Administration Division of STG, included Gilruth, Mathews, Faget, Low, Walter C. Williams, who was then still Chief of NASA's High Speed Flight Station, and E. M. Flesh, the engineering manager of Project Mercury for McDonnell. In addition, eight official advisers of the board and 16 observers from various other interested groups attended the meeting. The president of the corporation himself introduced his chief lieutenants: Logan T. MacMillan, company-wide project manager; John Yardley, chief project engineer; and Flesh. In consultation during the two days with some 40 McDonnell engineers, the Task Group recommended a total of 34 items for alteration or study. Of these recommendations 25 were approved immediately by the board, and the rest were assigned to study groups.41
Among the significant changes approved at this meeting were the addition of a side escape hatch, window shades, steps or reinforced surfaces to be used as steps in climbing out of the throat of the capsule, and a camera for photographing the astronaut. Robert A. Champine, a Langley test pilot who had ridden the centrifuge with Carter C. Collins and R. Flanagan Gray the previous summer to help prove the feasibility of the Faget couch concept, suggested more than 20 minor changes in instrumentation displays and the placement of switches, fuses, and other controls. Also attending this mockup review were Brigadier General Don D. Flickinger; W. Randolph Lovelace II; Gordon Vaeth, the new representative of the Advanced Research Projects Agency; John P. Stapp, the Air Force physician who had proved that man could take deceleration impacts of up to 40 g; and a relatively obscure Marine test pilot from the Navy Bureau of Aeronautics by the name of John H. Glenn, Jr.
When they returned to Langley Field, Task Group officials were aware as never before of the magnitude of their tasks. Conversations with more than 50 McDonnell [149] engineering group leaders had convinced them that more formal contract-monitoring arrangements were needed. Working committees and study groups had proliferated to such an extent that a capsule-coordination panel was needed. Gilruth appointed John H. Disher in mid-March to head the coordination temporarily. But by mid-June the panel was upgraded to an "office" and Disher was recalled to Washington by Silverstein to work with Low and Warren J. North.42
From a nucleus of 35 people assigned to STG in October 1958, the Group had grown to 150 by the end of January 1959. Six months later, in July, about 350 people were working in or with the Task Group, although some were still nominally attached to the research centers at Lewis or Langley.43
The rapid growth of STG, fully endorsed by Washington, was only one of the problems facing its management in the spring of 1959. Perhaps the most difficult lesson to learn in the first year of Project Mercury was the psychological reorientation required to meet new economic realities. Aeronautical research engineers who became administrators under NACA were still essentially group leaders of [150] research teams. But when NACA became NASA and embarked on several large-scale development programs, those in development, and in STG in particular, became not primarily sellers of services but rather buyers of both services and products. To manage a development program required talents different from those required to manage a research program, if only because Government procurement policies and procedures are so complex as to necessitate corps of experts in supply and logistics. Senator Stuart Symington of Missouri, one of the knowledgeable observers watching the transition at this time, remarked, "The big difference between NACA and NASA is that NASA is a contracting agency."44
26 "Status Report on Project Mercury Development Program as of March 1, 1959," Public Affairs Office, Langley Research Center.
27 Low, "Status Report No. 9 - Project Mercury," 2, 4; W. C. Moseley, Jr., interview, Houston, Sept. 21, 1965.
28 Willard S. Blanchard and Sherwood Hoffman, interview, Langley Field, Va., Jan. 6, 1964. Cf. their formal papers on configuration studies published after 18 months' lead time as TN D-223, "Effects of Nose Cone Radii, Afterbody Section Deflections, and a Drogue Chute on Subsonic Motions of Manned-Satellite Models in Reentry Configuration," March 1960; and as TM X-351, "Full-Scale Flight Test of a Proposed Abort-Escape System for a Manned Space Capsule from Sea Level," Aug. 1960; also Blanchard and James R. Raper, TM X-422, "Full-Scale Flight Test from Sea Level of an Abort-Escape System for a Project Mercury Capsule." Blanchard's work with tow rockets and the first full-sized model of the Mercury configuration was publicized by Aviation Week, which featured his picture on the cover of its April 1959 issue. Alternative modifications of the escape rocket system were being tested by Herbert G. Patterson using 1/4-scale boilerplate capsule-pylon systems in beach abort launches from Wallops Island.
29 For a résumé of these activities at Langley, see memo, Carl A. Sandahl to Assoc. Dir., "Langley Presentation to the Space Task Group," May 19, 1959. Cf. memo, Abe Silverstein to Dir., Aeronautical and Space Research, "Langley and Ames Research Center Support for Project Mercury," March 6, 1959, with two enclosures. See also memo, Lloyd J. Fisher to Assoc. Dir., "Flotation Investigations in Support of Project Mercury," May 12, 1959.
30 Albin O. Pearson, interview, Langley Field, Va., Jan. 7, 1964; memo, Pearson to Assoc. Dir., "Visit of NASA Personnel to Arnold Engineering Development Center, Tullahoma, Tenn.," March 5, 1959; memo, Moseley for files, "Summary of Project Mercury Wind Tunnel Program," Aug. 26, 1960. See also Marvin E. Hintz, A Chronology of the Arnold Engineering Development Center, Air Force Systems Command Historical Publication Series 62 - 101, June 30, 1963, 62.
31 "Pilot Support System Development (Live Specimen Experiment)," Report 6875, McDonnell Aircraft Corp., June 1959. Cf. "Test Results Memorandum," McDonnell Aircraft Corp., June 9, 1959. John H. Glenn, interview, Houston, Aug. 3, 1964; memo, Wilbur E. Thompson to Chief, Flight Systems Div., "Status of Impact Test Program," June 9, 1959.
32 Letter, Gilruth to Commanding Officer, Wright Air Development Center, March 26, 1959; Low, "Status Report No. 11," April 6, 1959. Cf. "Project Mercury Status Report No. 2 for Period Ending April 30, 1959," STG/Langley Research Center. On the history of parachute development for Mercury, see Joe W. Dodson, transcript of a taped discussion with Donald C. Cole, "Mercury Parachute History," September 1962.
33 William C. Muhly, interview, Houston, Aug. 9, 1965; see also Muhly's draft Ms., "Planning and Scheduling," May 28, 1963, for the Mercury Technical History. Regarding STG's first plans for astronaut pickup, see STG, "Recovery Operations for Project Mercury," March 20, 1959.
34 See Chapters IX and X, pp. 287 and 311 following. Lloyd Fisher of Langley worked on a torus landing bag for several months in 1959 before the honeycomb structures developed well enough to abandon the idea for a while. But reconsiderations of dry landing from an abort at the Cape or nearing Africa led Gerard Pesman, Faget, and Donlan to reinstate the pneumatic impact bag development late in 1960. Pesman, interview, Houston, Aug. 16, 1965.
35 E. Nelson Hayes, "The Smithsonian's Satellite-Tracking Program: Its History and Organization," Parts I and II, Publications 4482 and 4574, respectively (Washington, 1962-1964), I, 318.
36 Letter, J. W. Crowley to F. L. Thompson, "Request that LRC Assume Responsibility for Project Mercury Instrumentation Facilities," Feb. 20, 1959, with enclosure (Silverstein to Crowley, Feb. 16, 1959); Charles W. Mathews, interview, Houston, Sept. 23, 1965; and Low, comments, Oct. 5, 1965.
37 Hartley A. Soulé interview, Hampton, Va., Jan. 7, 1964. Soulé retired in 1962 to write histories of Langley and of the Mercury tracking network. Cf. memo, Soulé to Assoc. Dir., "Questions Concerning the Project Mercury Range . . .," April 13, 1959.
38 G. Barry Graves, interview, Houston, Feb. 17, 1964. Cf. memo, Graves to Gilruth, "Progress on Range for Project Mercury . . . ," Feb. 13, 1959.
39 Letter, Henry J. E. Reid to Silverstein, April 27, 1959, with enclosure (Soulé, "Tentative Plan for Operation of Range for Project Mercury"). Cf. earlier plans in letter, Reid to Crowley, March 9, 1959.
40 "Project Mercury Crew Station Description," Report 6710, McDonnell Aircraft Corp., March 16, 1959; "Model 133 Mockup Review Pictures," Report 6732, McDonnell Aircraft Corp., March 18, 1959. It is perhaps significant that a large sign behind the mockup in the McDonnell factory said, "When a change is not necessary, it is necessary not to change."
41 Minutes, "Model 133 Mockup Review," McDonnell Aircraft Corp., March 18, 1959.
42 Memos, Gilruth to STG/Langley Research Center, "Coordination of Meetings of Study Panels . . . ," March 20, 1959; and "Establishment of Capsule Coordination Office and Review Board," June 19, 1959; John H. Disher, interview, Washington, Sept. 2, 1965. For an overview of the nature and scope of Project Mercury as seen by STG at this time, see memo for files [and distribution among supporting groups], Purser, "General Background Material on Project Mercury," March 23, 1959.
43 Ms., C. F. Bingman for Project Mercury Technical History Program, "Organization," June 3, 1963, 5, 14. See also STG/Langley, "Status Report No. 2."
44 Senator Stuart Symington's remark is in Governmental Organization for Space Activities, 28. Cf. House Committee on Appropriations, 86 Cong., 1 sess. (1959), National Aeronautics and Space Administration Appropriations, Hearings, testimony of Hugh L. Dryden, 9. Faget recalled in interview the "family joke" of the symbols: NA¢A - NA$A.