Preliminary specifications for capsule and subsystems were mailed by the Langley procurement office to more than 40 prospective firms on October 23, 1958. Thirty-eight of these companies responded by sending representatives to the bidders' conference at Langley Field on November 7. The briefing was conducted by Faget, Alan Kehlet, Aleck Bond, Andre Meyer, Jack Heberlig, and several others from STG and Langley. The verbal exchange of ideas at this meeting was preliminary to corporate expressions of interest expected by STG before mid-November. After that the Task Group would mail out formal specifications as the basis for bid proposals to be submitted before December 11, 1958. After his part of the briefing, Faget was asked by one of the representatives whether the retrorockets described could also be used for escape. Faget said no and explained why not. He then made it clear that any alternative capsule configurations would be considered "provided that you incorporate the retrorocket principle, the non-lifting principle, and the non-ablating heat sink principle."30
Nineteen of the companies present expressed interest in the competition; they were mailed copies of STG's 50-page "Specifications for Manned Space Capsule" on November 14, 1958. This document, officially numbered "S-6," formally described STG's expectations of the missions, configurations, stabilization and control, structural design, onboard equipment, instrumentation, and testing for manned orbital flight, but significantly it did not deal in detail with reliability, costs, or schedules for flight testing.31
By December 11, the deadline for bid proposals, the list of original competitors had narrowed to 11; there was a late starter in Winzen Research, Inc., whose proposal was incomplete. All but three of these manufacturers had been engaged for at least a year with feasibility studies related to the Air Force plans for a manned satellite. Of the 11, the eight corporations with deepest investments were Avco, Convair/Astronautics, Lockheed, Martin, McDonnell, North American, Northrop, and Republic. The three other bidders were the Douglas, Grumman, and Chance-Vought aircraft companies. Significantly perhaps, certain other major missile and aircraft companies, like Bell, Boeing, and United Aircraft, were not represented. Bell was preoccupied with the Dyna-Soar studies; Boeing also was working on Dyna-Soar and had obtained the prime contract for the Minuteman missile system; and United Aircraft sent its regrets to Reid that it was otherwise deeply committed.32 Other military research and development contracts, such as those for the XB-70 "Valkyrie" and XF-108 were also competing for the attention of the aerospace industry.
The Space Task Group and NASA Headquarters meanwhile had worked out the procedures for technical assessment of these manufacturers' proposals and for contractual evaluations and negotiations. At Langley, a Technical Assessment Committee headed by Donlan was to appoint 11 component assessment teams to rate the contending companies in each of 11 technical areas. The classification  system set up by the Space Task Group to evaluate these competitors for the spacecraft contract illustrated the major areas of concern.
Between four and six research engineers sat on each of the following 11 components assessment teams: systems integration; load, structure, and heatshield; escape system; retrograde and landing system; attitude control systems; environmental systems; pilot support and restraint system; pilot displays and navigational aids; communications systems; instrumentation sensors, recorders, and telemeters; and power supplies. Each area was rated on a five-point scale ranging from excellent to unsatisfactory; the scores from these ratings were averaged to provide an overall technical order of preference.
All this had to be done over the Christmas holidays and while the Task Group was moving from the Unitary Wind Tunnel building on the west side of Langley Air Force Base to new quarters in an old NACA building on the east side. Early in January at NASA Headquarters a similar assessment team would gather to evaluate the competitors on their competence in management and cost accountability. MacDougall was to be the only Task Group representative on the "business evaluation" committee. Finally, a Source Selection Board, chaired by Silverstein at NASA Headquarters and including Zimmerman from STG, would review the grading, approve it, and make its final recommendation for the choice of the spacecraft contractor.33
Although virtually everyone in the Task Group participated in the process of selecting the capsule builder, there were other equally pressing tasks to be accomplished as soon as possible.Procurement of booster rockets, the detailed design and development of a smaller, cheaper test booster, and the problem of finding the best volunteers to man the finished product - these were seen as the major problems requiring a head start in the fall of 1958.
29 Link, Space Medicine in Project Mercury, 28. One of the best broad assessments of the "state-of-the-art" of aerospace technology at this time was prepared by the Rand Corporation under the direction of Robert W. Buchheim, and reissued as a Congressional report: House Select Committee on Astronautics and Space Exploration, 86 Cong., 1 sess. (1959), Space Handbook: Astronautics and its Implications, 105, 166.
30 "Questions and Answers from Bidders' Briefing for Manned Space Satellite," STG, Nov. 7, 1959, 3; George F. MacDougall, Jr., interview, Houston, Sept. 13, 1965.
31 "Specifications for Manned Space Capsule," specification No. S-6, Nov. 14, 1958, passim.
32 See letter, Boone T. Guyton, sales manager, Missile and Space Systems Div., United Aircraft Corp., to Henry J. E. Reid, Dir., Langley Research Center, Nov. 26, 1958; Ruben F. Mettler, Space Technology Laboratories, to Gilruth, Nov. 11, 1958. After the bidders' briefing, STG mailed additional material to prospective bidders. See letters, Gilruth to all bidders on prime contract for Mercury capsule, Nov. 25, 1958. Cf. letters, Reid to prospective bidders on Mercury capsule, Nov. 19, 1958. Back in the fall of 1954, the X-15 research airplane attracted nine companies to attend the bidders' briefing, and only four submitted bids. Walter C. Williams, interview, Houston, Aug. 23, 1965.