The negotiations conducted in Moscow had indicated by their variety and scope the growing complexity of the joint effort. At the executive level, the question of more rapid and frequent communications between the Soviet and American Technical Directors had been raised.  In the November briefing to Headquarters before the trip MSC had pointed out that preparations for a test mission could never be conducted by the slow process of exchanging letters through diplomatic mail: "If such a test mission is to be developed, we need to establish a method for more timely communications with the Soviets."14 In Moscow, Chris Kraft had raised this matter, urging NASA and the Soviet Academy to establish weekly or biweekly telephone conference calls between the Technical Directors, with these discussions being confirmed by telex. At first, Petrov had balked, saying that it would be too expensive. He argued besides that they would have to bring in their telephone people before they could have direct telephone conversations with the Americans. For this reason, he could not discuss the topic. Kraft insisted that telephone conferences and telex exchanges had been required in the American manned space program since Project Mercury. Gilruth added, "It was essential to permit an easy flow of information and to establish a system for reassurance that progress was being made." He told the Soviets that they "had to agree to this point or the mission would be impossible." Kraft and Gilruth hammered away on this subject for some time, and finally Gilruth told the Soviets that should they be unwilling to agree to the telephone conversations the NASA delegation might as well pack up and go back to Houston. After some hesitation, the Soviets decided to try the telephone telex approach, and this agreement had been included in the Summary of Results.15
During the executive group meetings, having declared that "a test mission appears technically feasible and desirable," the two sides did determine that it would be necessary to make an early decision about the practicality of scheduling a flight for 1975. With the American side proposing that the launch occur in the spring or summer of the year, the parties had included in the Results an agreement that each side would send the other by 1 April 1972 "a statement of its position on the prospects for the actual conduct of the test mission in 1975" and their concepts of such a mission. To pace the implementation of these decisions, the executive staff had drawn up a preliminary list of milestones, or major events, for the planning, design, and implementation phases of preparing for a test flight. (See box below.) This schedule was patterned after a standard NASA format, and the original draft would be subjected to further discussion prior to the April deadline. As the list grew, the need for closer communication became even more apparent. It also became clear that all letters, telexes, and telephone conversations should be coordinated by the Technical Directors. Many hands would work on the joint project, but they would have to be carefully orchestrated to assure success.16
Various questions and issues had been raised in each of the Working  Groups, and for the most part they had been resolved as the talks progressed. Group 1 completed the general documentation of its agreements on life support systems, coordinate systems, constraints on spacecraft configuration, and communications links between ground control centers. With respect to the proposed Apollo/Salyut test mission, the two sides spelled out the objectives of such a flight and listed the project documents that would have to be prepared for the mission. The chairmen of the Group agreed to a mutual exchange of data on launch windows within two months, on program information for the test mission by April, and on communications channels for the respective control centers within three months. The Americans also planned to provide a draft of an interface organizational plan for the project.17
Working Group 2 had also come to a number of significant decisions. They developed a list of guidance and control systems and other onboard equipment in the Soviet and American spacecraft that would have to be made compatible. The preparation of documentation covering the subjects of docking lights, docking targets, and contact conditions between spacecraft, as well as the technical data on control systems and radio tracking, progressed satisfactorily. This group planned to reorganize the documentation into two volumes covering general requirements for the future and specific demands on the systems proposed for Apollo/Salyut. For the test mission, the two sides would need to develop communications and tracking systems to an agreed set of technical requirements. An Apollo-type VHF ranging system would be installed in the Salyut as a backup system, and the Soviets had said they would study the issue of building their part of the onboard communications system versus using equipment provided by NASA.
Group 2 had also delved into the control and guidance problems relating to docking. For example, by considering the relative velocity of the two spacecraft, the docking system engineers established numerical values for the force with which the two vehicles might dock. The two sides also concurred on docking targets. One would be mounted in the center of the Salyut docking hatch, providing the Apollo CSM pilot with a dynamic visual reference for alignment. A second target, of the passive type used in the Apollo program, would be placed on Salyut where it could be seen from the command module through the crewman optical alignment sight. In addition, each side had been assigned work on control stabilization requirements for the two spacecraft and had been asked to look further into the design, development, evaluation, and installation of the docking target concepts.18 Meanwhile, Group 3 had concentrated on the problems of creating a universal docking mechanism.
14. MSC, "Review of Material for Next Meeting with USSR," 10 Nov. 1971.
15. Interview, Gilruth-Ezell, 25 Mar. 1975; and "Summary of Results," 29 Nov.-6 Dec. 1971.
16. "Summary of Results," 29 Nov.-6 Dec. 1971.
17. "Minutes of Meetings, Working Group No. 1," 30 Nov.-6 Dec. 1971 [retyped 30 Dec. 1971].
18. "Minutes of the
Working Group No. 2," 29 Nov.-7 Dec. 1971, with appendices.