During the spring months of 1972, the personnel of the MSC Engineering and Development Directorate pursued the design of an international docking system. Working concurrently with the North American Rockwell team and the Soviet Group 3 members, the Houston engineers were attempting to ensure the speedy development of hardware. Starting a contractor to work on a project before design was firm was not unusual. In the Apollo program MSC had followed the same approach in the design and development of the command and service modules, the lunar module, and their various subsystems. The iterative process of design helped to ensure the timely delivery of hardware and the maintenance of tight schedules.
The 27 March-3 April visit of the Soviet Working Group 3 members to Houston was essential to the NASA plan of having North American Rockwell start the detailed engineering of an Advanced Missions docking system. The four-man delegation led by Syromyatnikov quickly got down to the task...
Excerpt from Transcript of Telecon Between Manned Spacecraft Center, Houston, Texas, U.S., and Intercosmos, Moscow, U.S.S.R. from Approximately 9:30 to 10:45 CST
 ....of joining in defining the dimensions and specifications of the docking system. This information was spelled out in the minutes of their meeting and in four sheets of engineering drawings.* Bill Creasy and several of his colleagues worked with Yevgeniy Gennadiyevich Bobrov at the drafting table to lay out these first Soviet-American engineering drawings. Larry Ratcliff drew the capture ring and guides on drafting paper, and Robert McElya supplied the details of the structural interface ring, while Bobrov prepared a similar drawing for the structural latches. T. O. Ross then took these drawings and conducted a dimensional analysis to be sure that all items were compatible.
On 3 April, the two sides completed their drawings and wrote their minutes. These drawings were a blending of the way in which the Americans and the Soviets usually presented data on paper. Creasy said, "Their drawing procedure is different from ours and sometimes we joke and say that . . . [these Group 3 drawings] must violate the drawing conventions of at least the U.S. and Russia and probably several other countries." But each side could understand and work from the information as recorded, and that was the important point. Looking back on this effort, Creasy commented that, despite five subsequent updatings of the April drawings, the basic work only required some minor refinements and adding the tolerance dimensions.42
Agreement on technical specifications for the docking system cleared the way for NASA to begin discussions with Rockwell about building the docking module and the docking system and modifying the CSM. As MSC engineers worked with the potential contractor in drafting a statement of work for Apollo/Salyut test mission hardware, the procurement staff in Houston drew up their contracting plans.
At Headquarters, the agency's senior staff was looking into various political aspects of conducting a joint mission, and two issues were paramount in these discussions. First, congressional authorization and appropriations would have to be obtained before NASA could begin to modify or build the necessary hardware. Second, a bilateral agreement between the United States and the Soviet Union would have to precede the request for funds. George Low was given the task of determining how to resolve this issue.
* Following the formalization of ASTP in June 1972, these drawings became part of Interacting Equipment Document 50 004, "Apollo Soyuz Physical Interface Requirements."
Creasy-Ezell, 7 July 1975; and "Minutes of Meeting on Assuring
Compatibility of Docking Systems and Tunnels," 3 Apr. 1972.