The Partnership: A History of the Apollo-Soyuz Test Project|
 ...first-hand by men who had worked with and flown the Soyuz. Lying in the command module couches, the Americans could see and touch the controls, getting a better feel for the Soviet approach to manned space flight.
Lunney later thought about the briefing he received while lying in the commander's couch. Directly in front of him was the main control console. Starting at the upper left-hand corner of the instrument panel and proceeding clockwise, Shatalov explained the equipment. First, there was the rotating globe - the "space navigation indicator" - that gave the pilot his approximate position relative to the earth's surface. Adjacent to that instrument was a panel of lights that displayed the status of various spacecraft systems. Next, Shatalov indicated a television screen through which the commander could observe the docking. Then there was a projection screen for displaying aspects of the flight program visually, while other data were presented on a digital data display. Above that latter unit was a chronometer to keep track of flight times.
Shatalov then pointed to an optical device located just above Lunney's right knee. This navigation sight, used in conjunction with the television display during rendezvous and docking, gave the commander a fixed view of the scene directly ahead of the spacecraft. Next to this apparatus were a series of gages, switches, and additional clocks. With these, the commander could keep track of cabin pressures, temperature, and power levels and could also monitor time-critical control commands. On either side of the main console were located "command signal" panels with rows of lights and push buttons that permitted the crew to execute specific commands to the spacecraft systems. Manual control of the Soyuz was accomplished through two hand controllers at the commander's side. Both Lunney and Johnson noted the large blank spaces on the walls of the command module covered by an off-white, felt-like padding. For Lunney, "the very strong impression was one of simplicity - no circuit breaker panels, no large number of switches, not many displays."32
After getting a general orientation to the various Soyuz systems, the Americans were given an opportunity to look at the docking simulators. This set of trainers consisted of two command module mockups - one for active and another for passive rendezvous. These two simulated spacecraft could be maneuvered into the docked position with other small models of Soyuz, viewed by the cosmonaut either on the television monitor or through the docking periscope. After watching these replicas of the regular flight systems, Lunney and his associates felt that they had a much better understanding of Soviet rendezvous techniques. There were still unanswered questions, but this introduction proved to be a great aid in the technical discussions that occupied the next two days.33
 After the familiarization session with the spacecraft trainers, the men walked to the main building of the Cosmonaut Training Center, where they watched a motion picture about Yuri Gagarin's flight, following which they visited a manned space flight museum. Gilruth and the others saw the reconstruction of Gagarin's office, as well as all the memorabilia collected by the first man in space on his subsequent trips around the world. After the tour, the group retired to a mid-afternoon luncheon.
General Kuznetsov began the pre-meal formalities with a long, carefully prepared toast. He spoke directly to the NASA representatives and said in effect that he was relying upon them to exert their influence on the American government to ensure cooperation in space. He wanted the U.S. representatives to convey to their leaders the necessity for keeping space endeavors peaceful; he expressed his hope that space would not be turned into something evil. Lunney especially felt the personal nature of this message: "He was talking directly at and to us. He was saying to me that he was holding us responsible to see that space continued to be a peaceful place."34 Shatalov followed with a toast comparing the histories of the United States and the Soviet Union, in which he stressed the similarities of the two countries and their aspirations. The vodka and the meal behind them, the Americans and Soviets walked about the grounds at Star City.
As if this were not enough to occupy a full day, the Americans were taken back to Moscow for a visit to the major space museum housed on the grounds of the Exhibition of Economic Achievements. Following a ten-minute stop at the Rossiya, their evening was capped by a trip to the Bolshoy Theater for a performance of Rimsky-Korsakov's opera The Tsar's Bride.
Monday, 26 October, was given over to discussions* of rendezvous experiences and techniques and to descriptions of spacecraft docking assemblies. Glynn Lunney gave the first presentation, describing the spacecraft hardware capabilities NASA considered essential for orbital rendezvous, communications, guidance, and propulsion systems. For an international rendezvous, he saw that a number of issues would have to be studied - compatible equipment to provide information on the range between spacecraft and their rate of closure; suitable docking lights, reflectors, and targets; and vehicle-to-vehicle voice communications. Lunney also summarized for the Soviets rendezvous techniques as they had evolved through Gemini and Apollo. While there were many adequate techniques, the specific approach to the problem would ultimately depend upon the degree of  automatic or manual control in a given spacecraft. Therefore, an accommodation would have to be reached whereby the basically automatic, radar-controlled rendezvous of Soyuz could be matched with the essentially manual approach of Apollo. These were by no means irreconcilable differences, but they would require much study. Lunney closed by telling the Soviets that NASA expected its future rendezvous techniques to be an outgrowth of the ones he had described.35
Next Feoktistov explained the Soviet methods of rendezvous, which were designed to work either manually or automatically from ground commands, though they definitely favored the latter approach. According to Feoktistov, the Soviets considered rendezvous in three distinct phases - delivery of the active spacecraft to the vicinity of the target spacecraft, automatic rendezvous maneuver to stationkeeping distances, and final approach to docking. Going into more detail, Feoktistov said that the first phase could be approached in two ways, direct ascent or rendezvous following placement of both ships in orbit. Direct ascent required precise timing, so that the second craft could catch the target within its first revolution. More satisfactory, they had found, was a rendezvous after the two vehicles were in basically similar orbits. The path of the active craft would be adjusted by engine burns generated by ground-based computers and transmitted by radio to the onboard guidance and propulsion systems. This maneuver would bring the two ships to a range at which a mutual automatic search would begin by the spacecraft tracking systems.
Phase two of the Soviet rendezvous process started when the radar antennas locked on and the guidance system oriented the ships in the proper attitude - nose-to-nose. The main engine of the active Soyuz would be fired automatically as directed by the guidance system to bring the two craft to within a range of 300 to 400 meters. During the third phase, the final approach to docking (prichalivaniye, literally mooring) would be completed by firing the 9-newton (2-pound) translational thrusters. While this final phase could be completed in either an automatic or manual mode, the Soviet specialists seemed to prefer the hands-off approach.36
When discussion turned to the docking systems used to lock spacecraft together following rendezvous, Caldwell Johnson presented a description of the systems NASA had used during Gemini and Apollo, to preface his outline of future docking concepts.** According to Johnson, the configurations  of Gemini and the Agena target vehicle were nearly optimum for manually controlled docking. "The Gemini crewmen were in an excellent position visually to monitor the condition of the docking gear and to control their docking maneuvers." Furthermore, "both craft had full attitude and translation control capability, both as separate and connected vehicles." In Apollo, the command and service module geometry did not permit the crew to see the docking gear on either the command or the lunar module. This had not posed a serious problem, but Johnson noted the desirability of visual monitoring of the docking mechanism and process in future spacecraft.
After some further discussion of Gemini and Apollo docking experiences and a short film illustrating the final approach of the Apollo 12 command and service modules to the lunar module, Johnson turned to a fuller description of future concepts for docking gear. He told the Soviets that previous systems had functioned satisfactorily enough, "but our experiences . . . have pointed out areas where we feel that the docking gear of future spacecraft can be significantly improved." He then went on to outline seven design features that he and his designers believed would greatly facilitate docking operations in future spacecraft. The first four criteria emerged from the experiences with Gemini and Apollo; the latter three came from studies of future systems. Johnson elaborated on each of these points in turn.
Safety, of course, was the preeminent consideration. The docking gear should be fail-safe, "at least to the extent that the gear suffer no damage during impact when the spacecraft are misaligned too greatly to allow capture," Johnson said, and there should arise no situation in which automatic disengagement would be prevented. A failure to complete docking should under no circumstances preclude another attempt at capture. Johnson and his colleagues also believed that the astronauts should be able to transfer from one spacecraft to another without donning a spacesuit. This "worthwhile convenience" of shirtsleeve transfer required that the coupled spacecraft contain compatible atmospheres. While the Apollo and Soyuz cabins had dissimilar environments, Johnson told the Soviets that NASA was planning to use sea level pressure in the future, thus eliminating any transfer problems from that source. Another transfer-related consideration centered on eliminating any docking gear that might block the passageway between spacecraft. The Apollo probe assembly, which had to be removed after the command and service modules were latched to the lunar module, had proved very inconvenient. "Every attempt should be made to select a docking gear that does not block the very passage it intends to effect."37
The docking gear of all spacecraft to date - American and Soviet - had employed some variation of the probe and drogue. The probe, or male-like configuration, on one spacecraft would enter the drogue, or female-like...
There was or is no manner in which two spacecraft with only "probe" gear can dock together, nor is there any manner in which two spacecraft with "drogue" gear can dock together. That constraint has not been inconvenient to our limited spaceflight activities to date; but, we think we should avoid that constraint in future docking gear. We think future docking gear should exist in a limited number of standard classes, and that any new gear of a given class should be able to dock properly with any other gear of the same class.38
Such an androgynous*** docking gear should be designed so that either of the two spacecraft could dock and undock without the active support of the second vehicle.
As the final requirement in his list, Johnson saw the need for two structural modes for future docking gear, since subsequent spacecraft were expected to be much larger than the existing generation. Johnson doubted the desirability or practicality of using the docking mechanism to effect the structural joint between such craft. "We believe, rather, that the docking gear should be expected to provide only a relatively compliant structural joint; that the burden of rigid joining be assumed by the particular spacecraft's structural system." Caldwell then projected a Vu-graph of an androgynous docking system that combined all the design features he had mentioned.39
Described as a double ring and cone docking mechanism, this concept was one of Johnson's pet ideas. As was the case with many of his colleagues at MSC, Johnson had never really been satisfied with the Apollo probe and drogue arrangement. The history of that docking mechanism dated back to May 1962, when NASA and North American Aviation prepared a preliminary outline for space docking. As the investigation of docking gear progressed, seven different concepts were considered before the November 1963 decision to adopt the North American probe and drogue design.40 Among the rejected ideas was the ring and cone concept designed in 1963 by Houston's Preliminary Design Section of the Advanced Spacecraft Technology Division. But rejection of this idea did not mean that it was dropped. Over the years, several men including Johnson continued to propose variations on this theme.
Johnson revived a variant of this docking gear in 1967 for the orbital workshop of the Apollo applications program, which became Skylab. He called his 1967 androgynous design a double interrupted ring and cone.  The...
1961-1962. Solid cone as used in Project Gemini. Cone acted as guide for the active spacecraft during the docking.
Gemini concept as proposed in November 1963 for use in Project Apollo. When cone was sectioned to permit two to be put together, the sections became the guide fingers.
Cone and ring concept as proposed in November 1963 for use in Project Apollo. Attenuation system absorbed docking energies and permitted two systems to adapt to one another. Designed by J. Jones, W. Creasey, A. Bryant, and L. Ratcliff.
1967 double ring and cone docking system proposed by C. C. Johnson. After much analysis, Manned Spacecraft Center designers concluded that four fingers (or segments of a cone) would provide the best alignment for a universal docking system. J. Jones and T. Ross were leading individuals in the team which did the background work to this proposal.
 cone was divided into 12 discrete fingers or guides so that the "cone" of one gear would match the "ring" of the mating gear and vice versa. "The fingers of one will exactly intermesh with the fingers of the mating gear." The proposed mechanism, which would not block the passageway between spacecraft, was androgynous, could accept a passive partner, and was fail-safe. Furthermore, Johnson had separated the capture latching mode from the structural latching mode.41 His proposal was rejected again because the existing hardware was acceptable; the new concept did not possess sufficient superiority to merit such a change. Johnson had been working on a four-"finger" version of his earlier gear when he received word that he had been selected to visit Moscow. When Gilruth called his delegation together on 9 October, the designer had proposed to discuss his docking system with the Soviets, as being illustrative of one of the future approaches that NASA might take. Nobody knew how the Soviets would react to a discussion of hardware, but as it turned out, they were eager to talk about mechanical systems.42
While there were no specific Soviet comments regarding Johnson's presentation, they did give the Americans a detailed briefing on their Soyuz docking equipment. Vladimir Sergeyevich Syromyatnikov,**** their 37-year-old mechanical design expert for docking systems, described the probe and drogue system currently used on Soyuz.43 While similar in concept to the Apollo system, the Soviet "pin and cone" gear was not designed for internal transfer. Syromyatnikov told the Americans that the U.S.S.R. had adopted a docking mechanism without provision for internal transfer because it could be developed in less time. (This reinforced Johnson's opinion that there had been a "sense of urgency" associated with the development of Soyuz.) Returning to the main theme of this discussion, he reported that once capture was made, the Soviets employed an electric motor to retract the probe for final structural latching. In Apollo, the probe assembly was automatically retracted when the capture latches actuated the argon-gas-operated retraction mechanism. Lunney noted that the Soviet approach permitted repetitive docking and undocking, whereas Apollo was limited to two prime and two backup retractions. While the American system was sufficient for lunar missions, the heavier Soyuz docking equipment was more flexible.
The difference in approach to docking taken by the Soviets and NASA was also illustrated by the degree of precision required in the Soyuz docking  procedure. The Soviet docking equipment included electrical umbilical connectors contained in the face of the docking ring. These multiple prong and socket connectors required precise alignment, which the Soviets obtained by using 152-millimeter by 25-millimeter (6-inch by 1-inch) diameter guide pins. Once the head of the probe was engaged in the drogue, basic alignment having been accomplished by using docking targets, further alignment was completed by the guide pins of one craft entering sockets of the other craft. Like the American system, the Soyuz docking required matched pairs of spacecraft.
Syromyatnikov also talked briefly about a modified docking system that would permit internal transfers of crews and equipment. While this system had not yet flown, it appeared to be something that the Soviets planned to use in the relatively near future. Docking would be accomplished as in previous missions, but once the two ships were joined together the....
Soyuz probe and drogue after initial capture: (1) probe; (2) probe head with capture latches; (3) drogue; (4) hydraulic umbilical connector; (5) stop; (6) alignment pins; (7) docking structural ring; (8) drogue cone; (9) electric drive for retraction of probe stem; (10) ball joint; (11) probe guide; (12) lateral shock absorber; (13) electrical umbilical; (14) electromechanical damper.
Soyuz docking assembly after latching has been completed and hatches have been swung open to permit transfer of crewmen: (1) peripheral latch; (2) docking interface seal; (3) hatch cover drive; (4) docking (structural) ring; (5) hydraulic umbilical; (6) electrical umbilical; (7) active hooks; (8) passive hooks.
 ...probe and drogue assembly could be unlocked and swung out of the way. The passageway between the two vehicles would then be open for a shirt-sleeve transfer. This new mechanism was a real step forward from the first-generation docking system with its solid face, and the Soviets agreed to provide NASA with a fuller description.44
After a lunch break, the talks resumed with a discussion of Skylab by George Hardy. Skylab had grown from the desire to exploit more fully the launch vehicles and spacecraft that had been developed for the Apollo program. He told the Soviets that the Skylab hardware was designed in such a manner to permit it to be revisited, resupplied, and reused for extended earth-orbital missions. The flight lengths being projected for the three missions - 28, 56, and 56 days - appeared to intrigue his audience, especially in light of the Soyuz 9 flight the preceding June, which had lasted for a record 18 days. Hardy concluded with discussion on the rendezvous and docking operation associated with the program, showing the Soviets a model of the proposed spacecraft.45
Following a late afternoon adjournment, the Americans gave a party for their hosts at the home of the U.S. Embassy's Science Attache. During the socializing, Gilruth and Feoktistov shared stories and views on manned space flight. Since both men were among the "old timers" in their respective programs, they had a lot in common. Gilruth had wondered for years about who had been responsible for the development of the Soviet spacecraft, and he was particularly interested in Feoktistov's comments about having done the majority of the design work for Vostok, Voskhod, and Soyuz. But having risen to the position of Deputy Director of the Soviet manned space program, Feoktistov did not want to dwell on himself, so the conversation turned to other aspects of space flight - to Skylab, rotating space stations, and the ways one justifies manned space programs to scientists who prefer to use automatic probes. At evening's end, the Americans felt as if they had been to a reunion with old colleagues.46
Meeting again on Tuesday morning, the first hour was given over to further comments on Skylab by George Hardy and a description of Soyuz radio guidance equipment by V. V. Suslennikov. After that basic exchange of information, the men turned their attention to the topic of compatible systems to determine which aspects of that subject should be studied. At the end of this discussion, Feoktistov gave Gilruth a list of technical questions for which he felt the two sides should share answers. These questions indicated a basic concern in working toward compatible systems, and it seemed logical to all present that these problems should be divided into subject areas that teams of specialists could address. At Feoktistov's suggestion, three working groups were formed, following the precedent set  by the 1962 Dryden-Blagonravov agreement. One working group would ensure the compatibility of overall methods and means for rendezvous and docking; another would concentrate on establishing compatibility between radio, optical, and other guidance and communications systems, and the final group would attend to compatibility questions related to docking assemblies and tunnels that might be created. The representatives then worked up a schedule of events that would guide their efforts during the next six months.
Assuming that there would be a joint meeting of the working groups in about six months, the two parties agreed to exchange further data. During November by correspondence they intended to trade technical materials on radio guidance and rendezvous systems, spacecraft atmospheres, and systems for voice communications. Later that winter, each side would send its counterpart a draft outline of those technical requirements that were considered essential to compatibility. This paper work would allow the two groups of engineers to get an idea of how the other worked. The spring 1971 meeting would then concentrate on further defining technical specifications for compatible systems, both sides having worked independently on preliminary designs. While all the men present were ready to get to work, no one expected their work to bear early fruit.
After lunch on Tuesday, Frutkin, Lunney, Feoktistov, and Ilya Vladimirovich Lavrov drafted an agreement incorporating the points discussed that morning. Feoktistov was ready once again with a draft.As Lunney later reported, they discussed the document for a relatively short time before coming to full agreement. Feoktistov's original proposal was "98% of what we signed the next day."47 It became clear to the Americans that Feoktistov was a very efficient person and one of the prime movers behind the Soviet desire to develop complementary systems as soon as practical.
With their work out of the way, the Americans went on a tour of the lunar science laboratories and then had a brief discussion with M. V. Keldysh. The NASA representatives were impressed with both, developing an even deeper appreciation for the capabilities and accomplishments of Soviet space personnel. Gilruth especially understood Keldysh's comments about having to continually justify the space program to budgetary planners. After reviewing with his guests the progress that had been made, Keldysh invited them to dinner at the Prague restaurant. Following a pleasant evening of "shop talk" with Keldysh, Blagonravov, Petrov, and Feoktistov, the Americans returned to their hotel to rest up for their final day in Moscow. On the morning of 28 October, the NASA and Soviet representatives assembled at the Presidium of the Soviet Academy to sign the "Summary of...
...Results." In contrast to the ornate physical surroundings, the ceremony was simple but impressive. There was no smugness in their sense of accomplishment, but a feeling that the time had come for the two nations to cooperate in space. In just three days, they had reached an agreement to work together; now they would have to make good their pact.
* The Soviets present in addition to Petrov included K.P. Feoktistov, V. S. Syromyatnikov, V. V. Suslennikov, I. V. Lavrov, and N. Khabarin. Also joining the Americans was W. N. Harben, Science Attache, U.S. Embassy, Moscow.
** Johnson defined the terms used in discussing docking equipment as follows: "The term docking as applied to spacecraft operations defines the mechanical, temporary joining together of two spacecraft, generally for the purpose of crew and cargo interchange. In that same context, docking systems refer to the collection of spacecraft equipment designed to perform the docking operation. Docking gear refers more specifically to the mechanisms that accomplish the mechanical joining."
**** While Syromyatnikov was unknown personally to the NASA representatives, his reputation as an aerospace engineer had been known to the NASA community since his appearance at the Fifth Aerospace Mechanisms Symposium at the Goddard Space Flight Center, 15-16 June 1970, where he spoke on aspects of the Soyuz docking system.
33. Lunney to distribution, memo, 5 Nov. 1970; Gilruth et al., debriefing tape; and Vladimir Aleksandrovich Shatalov; "Komandnia rubka Soyuza" [Command module of the Soyuz], Aviatsiya i Kosmonovtika (Oct. 1970), pp. 34-36, describes the onboard systems of the command module and illustrates the control displays.
36. Lunney to distribution, memo, 5 Nov. 1970; and Viktor Pavlovich Legostayev and Boris V. Raushenbakh, "Avtomaticheskaya sborka v kosmose," paper presented at the 19th Congress of the IAF, New York, Dec. 1968 (available in translation as "Automatic Assembly in Space," NASA Technical Translation F12, 113).
40. North American Aviation Corp., "Apollo Monthly Progress Report," SID 62-300-4, 31 May 1962, p. 66; North American Rockwell Corp., Space Division, Kenneth A. Bloom and George E. Campbell, "The Apollo Docking System," SD 69-42, Aug. 1969, p. 1; and NASA, MSC, "ASPO Status Report," 4 Dec. 1963.
43. Frutkin sent a copy of Syromyatnikov's paper to Gilruth, see note, Frutkin to Gilruth, 3 Dec. 1970. Vladimir Sergeyevich Syromyatnikov, "Docking-Mechanism Attenuator with Electro-Mechanical Damper," in Fifth Aerospace Mechanisms Symposium: Proceedings of a Conference Held at Goddard Space Flight Center, Greenbelt, Maryland, June 15-16, 1970, NASA SP-282 (Washington, 1971), pp. 43-48. Following his paper, Syromyatnikov showed a movie, "Docking of the Soyuz IV and V," and gave a narrative description of slides made from the article "Linked Soyuz Spacecraft Shown by Soviets at Japan's Expo 70," Aviation Week & Space Technology, 27 Apr. 1970, pp. 70-74. "Discussion: Soviet Spacecraft" is presented on pp. 49-57 of the Proceedings. Bloom and Campbell presented "Apollo Docking System" at the same symposium (pp. 3-8 of the Proceedings). This talk was a variation of their presentation cited in note 40.
44. Lunney to distribution, memo, 5 Nov. 1970. On 28 October, the Soviets gave the NASA representatives four papers: "Kratkoye opisaniye stykovochnogo ustroystva kosmicheskikh korabley tipa Soyuz" [A short description of the docking device of "Soyuz" type spacecraft]; "Kratkoye opisaniye stykovochnogo ustroystva kosmicheskikh korabley tipa Soyuz (S vnyutrennim perekhodom)" [A short description of the docking device of "Soyuz" type spacecraft (with internal passage)]; "Opisaniye printsipialnoy skhemy sblizheniya i prichalivaniya kosmicheskikh korabley tipa Soyuz" [A description of the conceptual arrangement for the rendezvous and docking of "Soyuz" type spacecraft]; and "Kratkoye opisaniye radioapparatury sblizheniya kosmicheskikh korabley tipa Soyuz" [A short description of the radar approach equipment of "Soyuz" type spacecraft].