Category The Story of Manned Space Stations

In a 1946 summary of his work during World War II, Wernher von Braun prophesied the construction of space stations in orbit. The design, which owed a great deal to the earlier work of Noordung, consisted of a toroidal station spun to provide artificial gravity. Von Braun elaborated on this initial design at the First Symposium on Space Flight on 12 October 1951 hosted by the Hayden Planetarium in New York City. The design was popularised in 1953 in a series in Colliers magazine, illustrated with a gorgeous painting by Chesley Bonestell.

1948—THE BRITISH INTERPLANETARY SOCIETY STATION—H. E. ROSS

In a paper presented to the British Interplanetary Society (BIS), and reprinted in the Journal of the BIS in 1949, H. E. Ross described a manned satellite station in Earth orbit that would serve as an astronomical, zero-gravity, and vacuum research labora­tory, and also serve as a way-station for the exploration of the moon. His suggested design comprised a circular structure that housed the crew of the space laboratory

(numbering 24 specialists and support personnel) as well as telescopes and research equipment. The station, he suggested, could be resupplied with oxygen and other life – support essentials by supply ships launched every three months.

Salyut 1 had not been a failure; the death of the returning crew was tragic, but the space station itself had been blameless. The Soviet space organization was keen to launch another as soon as possible. Of course they had to wait until the Soyuz ferry vehicle was ready to resume flight. Arguments raged over the best way to achieve a safer Soyuz design, Chief Designer Vasily Mishin argued that simply adding space – suits to the capsule was not the right answer, it limited the crew to two and seriously reduced the cargo the ferry could carry to and from orbit in addition to the crew. However, he was overruled by the Secretary of the Central Committee, Dmitri Ustinov, who was absolutely determined that no cosmonaut would be launched into orbit without a spacesuit ever again. Mishin continued to argue that reliability of the systems was the best method of ensuring the safety of the crew, but he was told in no uncertain terms that Ustinov’s word was final, and that pressure suits were to be installed. This required a new version of the Soyuz spacecraft that would only have an orbital lifetime of two days. This was necessary as the solar arrays of the previous version had to be removed to save weight, and the on-board batteries would only last for that limited time.

After the “civilian’’ first station, it had been decided to introduce the first pure Almaz design, designated OPS-1, albeit using the Soyuz craft as the ferry instead of the TKS. The Almaz design also differed from the first Salyut in that its docking port was at the rear of the station. OPS-1 made it to Baikonur in the midst of the harsh winter of January 1973, and during the next 90 days military testers and civilian specialists prepared it for launch. The OPS-1 blasted off into orbit on 3 April 1973. Since the authorities did not want to disclose the existence of two space station projects in the USSR, and particularly, to reveal the development of the military Almaz, the OPS-1 was announced as Salyut 2 upon reaching orbit. It was given the Salyut name to disguise its military configuration, but it was different to the space station that had preceded it. It was several meters shorter, but weighed about a ton and a half more. In the center of its living compartment a huge camera was installed

in the “floor” and the station had a much higher level of automation to reflect the reduction in the Soyuz crew.

Unfortunately this new station did not last long enough for any crew to board it, and perhaps this was just as well, because 13 days after launch an electrical fire in the propulsion unit spread to the main compartment, explosively decompressing the station and sending it spinning out of control until it broke up. The official investiga­tion concluded that as a result of a faulty welding, one of the lines in the station’s propulsion system had burst during an engine firing and the plume of flame had burned through a pressurized hull. However, future findings were to cast doubt on this theory. Careful analysis of fragments detected in orbit, showed that three days after the launch of the OPS-1 the upper stage of the Proton rocket that had delivered the station apparently exploded as a result of pressure changes in its tanks resulting from overheating. The stage carried about one tonne of unspent propellant, and the explosion created a cloud of debris in the proximity of the station. The speed of some debris differed from that of OPS-1 by as much as 300 ms_1. Eight days later, a piece of this orbital junk apparently hit the station. However, despite all this secrecy and the attempt to cover up the military nature of the station, western observers almost instantly managed to discern the military nature of the new spacecraft. An article appeared in the September 1973 issue of Aviation Week, which read, “Soviet pench­ant for secrecy within its own space program has lead to a widespread, but erroneous, belief that a Salyut spacecraft failed while in orbit. The spacecraft, which the Soviet press and information agencies called a Salyut, was launched Apr. 3 and apparently suffered a catastrophic failure on Apr. 14. However, the spacecraft transmitted on a different frequency than previous Salyuts and now is believed to have been a different spacecraft. The reports initially issued by the Soviets apparently were incorrect because of an attempt to keep secret the actual nature of the spacecraft. Telemetry transmissions from the spacecraft were similar to those monitored earlier from Soviet reconnaissance satellites.” Although the Almaz name was not known in the West for many more years, these stations had become identified in the West as “military Salyuts”.

Undeterred, the Soviets launched another station only a month later. This was not an Almaz, but the third station in the DOS series. DOS-3 carried several improvements over the earlier configuration. It had improved solar arrays in an effort to double the overall lifetime of the station from the 90 days of the two previous stations. In most other respects, however, the station was basically the same, although more thought had been given to automating systems to accommodate the reduced crew of two. Unfortunately, due to errors in its flight control system, and while out of the range of ground control, the station fired its orbit-correction engines until it ran its tanks dry, and a week later re-entered the Earth’s atmosphere. Since the station had reached orbit, and therefore been tracked by western ground stations, the Soviets had to acknowledge its existence but, in a effort not to give anything away, designated it Cosmos 557 as a form of disguise.

The Soviets finally enjoyed some success with the launch of Salyut 3, a station of the Almaz design, in June 1974. The OPS-2 space station really was a reconnaissance platform, for it housed a massive 6-meter camera in its main compartment and had a capsule for the high-resolution film to be returned to Earth independently of the crew. In all 14 cameras were to be used on board. The other notable feature of this station was the modified aircraft machine gun that was mounted near the front port for station defence! In order to point it at the target the crew had to change the attitude of the entire station.

When the Salyut 3 station was launched a small group of teachers and school children in Northamptonshire, England, were glued to their radio receivers. The group would later become known simply as the Kettering Group, but for now physics teacher Geoffrey Perry and some of the pupils from Kettering Grammar/Boys School

had no particular name. They had for some years been following the satellite launches from both the U. S.A. and the Soviet Union by means of radio receivers within the school. He and his team of teachers and pupils had amassed a great deal of knowl­edge, particularly about Soviet satellites, since the launch of Sputnik 2 in 1957. Mr. Perry correctly identified launches from a site other than Baikonur in 1966, which would be later known as Plesetsk, and was also the first to record evidence of the first unmanned Soyuz test after the tragedy of Soyuz 1. Now with the launch of Salyut 3, they hoped to positively identify the station for themselves. But when they listened to the same channels that they had listened to previously for manned Soyuz

missions and the Salyut 1 station, they could hear nothing. The same thing had occurred the previous year with Salyut 2, and they wondered why this could be. It was later determined, with the help of other radio amateurs, that the station was using a frequency only usually used by military reconnaissance satellites. Although it was immediately apparent that this change of frequency meant that the station was military in nature, it was clear that it was being operated differently than the previous Salyut station. They hoped to confirm their hypothesis when the inevitable Soyuz spacecraft was launched to dock with the new station.

The crew of Soyuz 14 were Pavel Popovich and Yuri Artyukhin, both military officers, who were launched on 3 July 1974 and docked later that same day.

According to Popovich, the on-board automated rendezvous system delivered the Soyuz spacecraft only 600 m from the station and from a distance of 100 m the crew switched to manual control. Popovich remembers taking off his spacesuit gloves, (unpressurizing his suit, as a result) in order to make it easier to control the craft. The Kettering Group were able to identify for themselves that the Soyuz was only manned by two cosmonauts, and determined the identity of its commander, and they made a press announcement to the world through Reuters before the Soviet Union had even officially announced the launch. By comparison the U. S. CIA had no such detailed information; in a National Intelligence Estimate dated December 1973 they seemed only to be aware of the civilian Salyut program, and gave no indication that they had any information regarding the military Almaz program.

Popovich and Artyukhin entered the OPS-2, having docked at the rear, on 4 July 1974 and spent 15 days on board. According to official sources, the “remote-sensing

equipment” was activated on 9 July, followed by several days of photography of the “Earth surface”. Central Asia was among officially disclosed targets of the station’s cameras. Western sources also say a set of targets laid out near Tyuratam was photographed to test the capabilities of the surveillance hardware. Several times during the mission, an on-board alarm system woke up the crew; however, it proved to be false. During the flight, the cosmonauts reportedly checked the systems on board, adjusted the temperature inside the station, moved some ventilators and completed other housekeeping chores. They also reloaded the station’s on-board cameras and placed exposed film into the space station’s return-to-Earth capsule.

The second crew consisted of commander Genadi Sarafanov and flight engineer Lev Demin, and they were launched on board the Soyuz 15 spacecraft on 26 August 1974. However, problems with the rendezvous system on board the Soyuz during the approach to the station forced officials to cancel the docking attempt. The spacecraft returned to Earth after a two-day flight, the limit of the Soyuz’s orbital endurance, and was forced to land under night-time conditions. Typically for the period, official sources reported only that the Soyuz 15 crew “tested various rendezvous modes during its mission’’.

Two decades later, the official history of RKK Energia revealed that when Soyuz 15 reached a distance of 300 m from the station, the Igla (“Needle”) rendezvous system, failed to switch to the final-approach mode and instead started implementing a sequence that would normally be executed at a range of 3 km from the station. On commands from the Igla, the Soyuz fired its engines, accelerating itself in the direction of the station. The relative speed of Soyuz 15 to the OPS-2 reached 72kmh-1, zooming by the station at a distance of 40 m. As the crew failed to realize the problem (and to shut down the Igla), the rendezvous system attempted to re­acquire radio-contact with the target and sent Soyuz 15 to the station twice more each time narrowly avoiding a collision. By the time ground control commanded the deactivation of the Igla, the crew only had enough propellant for the descent back to Earth.

Due to lengthy modifications in the wake of Soyuz 15’s rendezvous problems, no further expeditions to Salyut 3 could be staged. The return-to-Earth capsule was jettisoned from the OPS-2 on 23 September 1974 and successfully recovered on Earth, and the station was de-orbited on 24 January 1975 over the Pacific Ocean.

According to official Soviet sources, the seven-month flight of Salyut 3 exceeded more than twice the originally planned flight duration. Soviet publications also disclosed that Salyut 3 was the first space station to maintain constant orientation relative to the Earth’s surface. To achieve that, as many as 500,000 firings of the attitude control thrusters had been performed. This fact also hinted to Western observers that Salyut 3 had perhaps carried out a reconnaissance mission.

Years later it was revealed that shortly before de-orbiting OPS-2, ground con­trollers commanded the “self-defence” gun on board the station to fire. According to Igor Afanasiev, an expert on the history of space technology, firings were conducted in the direction opposite to the station’s velocity vector, in order to shorten the “orbital life’’ of the cannon’s shells. A total of three firings were conducted.

In “Analysis of Orbital Systems,” a paper read at the fifth congress of the International Astronautical Federation in Innsbruck, Austria, Krafft Ehricke described an orbital station. Arguing that a very large space station was neither necessary nor desirable, Ehricke postulated a four-man design that might serve a number of different purposes, depending upon its altitude and orbital inclination. He suggested that such a station might be used for a variety of scientific research, for orbital reconnaissance, as an observation platform, and as a launch site for more distant space ventures. Later in 1958 Ehricke outlined the design for this station and called it Outpost. It would consist of an empty Atlas rocket equipped only with a pair of two-man gliders to serve as lifeboats, and could be powered by a nuclear reactor. Three further launches by Atlas-Centaur boosters would carry all of the remaining

The 1948 BIS Station

equipment required by the station. The crews would also be launched by Atlas – Centaur. Future plans called for Outpost II and III, each of which would be bigger than the last, consisting of clustered Atlas boosters, with the whole station spinning to provide artificial gravity to the occupants in either end.

Salyut 4 differed from Salyut 1, the previous successful DOS design, by having three sets of solar arrays, just as the doomed Cosmos 557 had. It also included some additions for crew comfort, including a table for the crew to eat at which supplied hot and cold water for rehydrating their food packs. The navigation system for the station was now semi-automatic, to allow the crew more time for experimentation. It was launched on 26 December 1974, and was followed on 11 January 1975 by Soyuz 17 with a crew of two, Alexei Gubarev and Georgi Grechko, both making their first space flights.

Their docking was achieved effortlessly, and they soon settled into the mission, working for six days a week, with a day off to spend largely as they wished. Their enthusiasm for their work was such that they worked longer hours than anticipated, and also ate more than planned, which had to be controlled as there were only so many supplies on board. Eventually they were told to slow down and take more time off, which they reluctantly did. The Soviets were still working to discover the best compromise between work and rest for the cosmonauts’ working week. The crew returned to Earth on the 7 February after 30 days in orbit, a new Soviet record of endurance, and were found to be in good physical and mental shape. However, it was decided that the exercise regime for future crews would be stepped up slightly, especially in the later stages of the mission to ensure that they were in the best condition for re-entry and adaptation to Earth’s gravity.

The launch of Soyuz 18 on 5 April was rather more dramatic, and once again the Soviets failed to get a mission to a space station. A fault with the separation of the main booster stage caused the abort tower to be used for the first time in manned spaceflight, causing the crew, Vasili Lazarev and Oleg Makarov a very uncomfortable 15-g ride before the capsule landed in snow. The next launch attempt on 24 May was also called Soyuz 18, and the previous failed flight simply referred to as “the 5th April anomaly’’. This crew, Pyotr Klimuk and Vitali Sevastyanov, reached orbit successfully, and docked with Salyut 4. Their task was essentially to carry on the

work started by the previous crew, but this time the Soviets tried to schedule the workload more logically. They would work for several days on one type of experi­ment before moving on to the next; a significant step forward. Of course, there was also maintenance work on the station to be carried out between scientific experi­ments, but again experience from previous missions was paying off, as items such as filters, pumps etc., had been made much easier to replace and service than previous designs, cutting down on time and frustration.

A new mission was launched on 15 July 1975. Although this mission did not involve Salyut 4, it did signify the first co-operation between the Soviet Union and the United States of America: ASTP, or Apollo-Soyuz Test Project. Discussions for such a mission had been taking place for several years, as mentioned in an earlier chapter, but the options were soon narrowed down to one: the docking of an Apollo Com­mand and Service Module with a Soyuz spacecraft. On 24 May 1972, U. S. President Richard Nixon, and Soviet Chairman Alexei Kosygin, signed the agreement that would make ASTP a reality. It was part of a much larger agreement that covered all manner of scientific co-operation, including space flight. Despite the air of co­operation, there remained “discussions” about various aspects of the mission. Which spacecraft would launch first? NASA assumed that Apollo with its longer mission duration would be the first to launch. That way if Soyuz was delayed for any reason, Apollo could simply wait until it arrived. The Soviets disagreed, stating that they would launch first, and wait for Apollo; if Apollo were delayed, they would launch a second Soyuz if necessary. This came as something of a surprise to NASA mission planners, as they had not previously heard anything about a second Soyuz being prepared for this mission. The actual docking posed even more problems, both technical and political. What form would the docking mechanism take? Both nations so far had used a male and female docking mechanism; which nation would take which role? The Soviets were rather more chauvinistic in this area, not wishing to take the “lesser” role of the female as they saw it. It was finally agreed that the docking system would be an androgynous one that equalized the two nations, but this also presented another problem. Which spacecraft would be the active (moving) ship, and which would wait (stationary) for the docking? The Apollo was clearly the more maneuvrable spacecraft, and so the Soyuz would have to wait to be docked with by the Apollo. Unfortunately, the problems did not end there. The atmospheres of the two spacecraft were very different. Apollo’s atmosphere consisted of 100% oxygen at a pressure of 0.34 atmosphere, whilst the Soyuz was an oxygen/nitrogen mix at 1.0 atmosphere. Clearly, it would be possible to simply float from one spacecraft to the other without suffering from the bends, so the docking mechanism would also have to double up as an airlock. With modifications to both spacecraft to allow the lowering of cabin pressure to make the transfer between the two craft quicker achieved, the major technical problems had been overcome. The first of the two crews were announced in 1973; the U. S. crew would consist of commander Tom Stafford who had previously commanded Apollo 10 and Gemini 9, and flown as pilot on Gemini 6. The Command Module Pilot would be Vance Brand, who would be making his first space flight after backing up the last two Skylab crews. The third crewmember had been waiting for a flight for a long time, after years of selecting other astronauts for their missions Deke Slayton, a member of the original Mercury astronaut group, would finally make it into orbit. The Soviets followed with their own crew announce­ment a few months later. This was a first, as crews for Soviet space flights had never been announced in advance before. The commander of Soyuz 19 would be Alexei Leonov, who we know all about from his travails during the crew selection for Soyuz 11. His flight engineer would be Valeri Kubasov, who had been removed from the Soyuz 11 crew for medical reasons, but was long since recovered. He had flown

previously on Soyuz 5 and had spent time on Salyut 6; in fact he had more flight experience than his commander.

With the crews announced, training for the flight could now begin. Learning each other’s language proved to be the most difficult task for both crews; something that would not change much over the coming years. The problem did not end with the crews of the spacecraft, the ground controllers and technical experts also needed to get up to speed on their counterparts’ language, a task that is particularly difficult where technical jargon is concerned.

Apollo-Soyuz finally got underway when Soyuz 19 was launched on 15 July 1975. With Soyuz safely established in orbit, Apollo was launched to give chase. Almost two days later, the two spacecraft docked without difficulty. The two crews spent 47 hours docked together, with members of each crew visiting the other’s spacecraft. Mission rules dictated that neither vehicle would be left unmanned at any time. After the docked phase of the mission Soyuz 19 returned to Earth almost immediately even though this Soyuz was equipped with solar panels like previous versions, and could stay in space for longer than its space station specific counter­parts. Apollo stayed in orbit for a further three days to conduct experiments that

would have to last NASA for a while, this being the last U. S. manned mission until the space shuttle was ready to fly, at this time expected in 1979.

It has been suggested that ASTP was little more than a political show, but this opinion sells the program short. In truth the idea may have been born out of political needs by both the U. S. and the Soviet Union, but that fails to take into account that many of the people that worked on this mission from crews to support staff and technical designers from both countries would later work together again on Shuttle – Mir, and ultimately the International Space Station (ISS). Relationships that were forged during ASTP would endure to smooth new relationships in the 1990s. It has been said that neither side learned very much; the U. S. engineers say that most Soviet equipment was Gemini era to them. But both countries did learn that it was possible to work together, and in the longer run that was sure to be worth something.

Meanwhile the crew of Salyut 4 continued their mission for a few more days before they too returned to Earth on 26 July, after 63 days in orbit. Before their departure they fired the engines of Soyuz 18 to raise Salyut 4’s orbit. This was the first time that such a maneuvre had taken place, previous orbit-boosts had been under­taken using the stations own propulsion. Upon their return the crew walked from their capsule to the medical tent, obviously in better physical condition than previous crews had been. Their mission had paved the way for longer duration flights, possibly involving rotating crews on a new space station. But Salyut 4’s mission was not over. Soyuz 20 was launched on 17 November 1975, and unusually for such a designation it carried no crew. It followed a different flight profile than usual, docking with Salyut 4 after two days rather than the one day that had been flown by manned up until now. Once docked, Soyuz 20 remained powered down until the end of February 1976. It later became apparent that this mission was a test of the flight profile and duration of an unmanned cargo craft. Once the craft had returned to Earth, examinations of its systems led Soviet engineers to place a 90-day limit on the amount of time that a Soyuz could safely spend in space.

Salyut 4 had been a great step forward for the Soviet space station program, after the difficulties of its predecessors, and had proved the procedures and technology that would be needed for the next generation of stations.

The next space station was Salyut 5, and it was launched on 22 June 1976. It quickly became apparent from the telemetry that this was another Almaz reconnaissance platform, identical to Salyut 3, but without the machine gun. An all-military crew of Boris Volynov and Vitali Zholobov was launched on Soyuz 21 two weeks later. The crew carried out some scientific experiments, but their primary mission seemed to involve observations of a military exercise that was underway in Siberia. They seemed set for a fairly long-duration mission, and indeed Soviet radio had reported on 19 August that solar radiation levels were such that the crew would be able to carry out a “prolonged flight’’, but five days later the same radio station reported that the crew were in the process of returning home. When they clambered out of the capsule after a night landing, it became evident that they were suffering from the effects of their mission, most likely because they had not started their pre­return exercise regime. All evidence seemed to point to the fact that the crew had returned much earlier than planned; but why? There were several suggestions, but the most likely seemed to be that the station’s atmosphere had somehow become con­taminated causing the crew to abandon ship. One speculation in the West was that one or both crewmembers had suffered mental or physical problems that forced their return. It was also suggested that Zholobov in particular had suffered debilitating homesickness, and as a result had not followed his exercise regime. It has since come to light that perhaps the two crewmembers did not get along, and perhaps their hostility got to the point that returning them to Earth was the only option before physical harm was caused. Whatever the reason, Salyut 5’s first manned mission had been abandoned early, and a crew needed to return as soon as possible to carry on the work. The next flight, that of Soyuz 22, made use of the back-up vehicle from the ASTP mission, and was not a flight to Salyut 5. Soyuz 22 was a week-long flight that concentrated on Earth photography using a special East German built camera. The fact that the next crew to visit Salyut 5 was launched within 2 months of the landing of the previous one, suggested that not too much could have been wrong with the station. The crew of Vyacheslav Zudov and Valeri Rozhdestvensky were to check on the condition of the station, and carry on with the experiments that were still left on board. However, all was not to go smoothly. The mission of Soyuz 23 on 14 October proved to be dramatic. The automatic rendezvous system malfunctioned almost as soon as it reached orbit, and for some reason not made clear by Soviet officials the crew did not attempt a manual approach and docking, but waited for the first opportunity to land. When the landing attempt came, things began to go wrong. After re-entry, the capsule descended on its parachute in the darkness, but was blown off course by a blizzard and it landed in Lake Tengiz. This was not in itself a problem as the Soyuz had been designed to land in water if necessary. Although the capsule landed in relatively shallow water, it was at least 5 miles from the nearest shore, and the water was freezing. Recovery by boat was therefore impossible, and helicopters could not locate the spacecraft as thick fog engulfed the area. The crew were forced to spend a very cold night in the capsule, which by now had no power reserves, and therefore no heating. At first light, the fog had cleared sufficiently to allow helicopters to attach lines to drag it to shore and end the exhausted crew’s ordeal. As it was, no real damage was done, but it is worth reflecting on what might have happened to a more weakened crew that had perhaps spent months in orbit, or been forced to come home early…

Viktor Gorbatko and Yuri Galzgov were launched on 7 February 1977 on Soyuz 24 for what would prove to be a short mission. Again when an automatic docking was attempted the system failed, but on this occasion a manual docking was attempted and achieved. The crew entered the station wearing breathing apparatus, but it did not take long to determine that the air was clear. Whether this procedure was really necessary, only the Soviet space officials know. However, the crew did take the opportunity to test a new procedure to clear the station’s atmosphere of any potential contaminants. They had brought some equipment with them that would allow the existing atmosphere to be vented and replaced with fresh supplies of air stored on board. Basically, the old air was allowed to leak out of one end of the station whilst at the same time fresh air was pumped in at the other end. Interestingly, the crew remained on board the station whilst this procedure was carried out, rather than retreating the Soyuz as one might expect. Shortly after this test, the crew began to prepare to come home, packing up their experiments as well as those left behind by the Soyuz 21 crew. The combined equipment and experiments were far more than the Soyuz could return by itself, so use was made of Salyut 5’s own descent capsule, designed for just such a purpose; it would return to Earth a day after the crew. The station had been left in a good state of repair, and Anatoli Berezovoi and Mikhail Lisun were already in training to attempt an unprecedented third period of occu­pancy, but due to the run of ill-luck the Soyuz spacecraft that had been allocated to the Salyut 5 programme had all been used, and there simply was not the budget nor the time to build a new Soyuz during the remaining lifetime of Salyut 5. Soyuz 24, therefore, became the last mission to a military space station. Salyut 5 re-entered the atmosphere on 8 August 1977 when all of its remaining fuel had been depleted, and it was clear that it would host no more missions.

In 1959 Wernher von Braun and his team issued the Project Horizon report. This outlined the establishment of an entire lunar base by 1964. Von Braun at that time was with the Army Ballistic Missile Agency, and had yet to be transferred to the newly formed NASA. As part of the Horizon report, he advanced the theory that he had conceived years earlier for using a booster’s spent stage as a space station’s basic structure. The Earth orbital station was a major requirement for Project Horizon to succeed as there were no boosters on the drawing boards that could provide anything like the thrust needed to send the men and equipment for the lunar base to the moon under a direct ascent mode. An Earth orbit rendezvous would be required for refueling prior to flight to the moon. The “mode question’’ would of course later resurface when Project Apollo began. Project Horizon envisioned moving quickly to an early improved station constructed from 22 upper stage shells. Prior to any expansion of lunar outpost operations, sufficient tankage would have been placed in orbit to permit construction of two or three such stations. The orbital station crew strength was approximately 10; however, they would be rotated every several months. It was proposed in the report that the Earth-orbiting station created during the construction of the lunar outpost would continue as a separate program making use of the resources created rather than wasting them. The contributions that the space station would have provided were as follows:

• space laboratory, acclimatisation, and training capability for personnel;

• space laboratory for equipment;

• material storage space;

• low-altitude communication relay;

• Earth surveillance (perhaps a security consideration in this specific operation);

• space surveillance;

• meteorological surveillance;

• survey/geodesy data collection; and

• instrumentation for the test of Earth-to-space weapon effects.

Salyut 6 represented the major step forward in space station operations that the Soviets had been planning for some time. Launched on 29 September 1977, it featured a second docking port, as well as an Extravehicular Activity (EVA) hatch. The second docking port was a significant addition because it allowed the station to be resupplied by Progress cargo spacecraft, an essential capability for long-term habitation. It would also allow for the possibility of visiting crews who would dock with the station, stay for about a week, and then return in the older Soyuz leaving the new one for the long-duration crew.

The concept behind the Progress spacecraft was a simple one, and solved the problem that all previous space stations, including Skylab, had encountered. How do you keep a long-duration crew in orbit, when they are eventually going to run out of supplies of food, clothes, and of course, oxygen? The Soyuz spacecraft could only carry so much cargo in addition to its crew, but if the crew, and all of their life support systems were removed, this released a lot more room for cargo. The result was to become the Progress, essentially a leaned down Soyuz meant only for cargo and fuel, and designed only to make a one-way trip. The heat shield was also removed; it was unnecessary because the idea was that once the resident space station crew had unloaded all of the fresh cargo, they would load the craft with all of their unnecessary equipment, and rubbish, and it would then undock and be remotely commanded to re-enter and burn up. This also made the separate descent module unnecessary, and it was instead used as a fuel tank to allow the Progress to replenish the propellant tanks of the space station. In truth, it would become apparent in later years that the Progress did not solve all of a space station supply problems. It could not return anything to Earth obviously, which meant that crews returning to Earth would continue to need to bring back experiment results with them in the Soyuz, which had a limited return weight. It also turned out that not all of a stations unwanted material could be disposed of in a Progress, and that long-lived space stations would accumulate more and more clutter.

The new ability for crews to make short visits to an accupied station opened up the prospect for the first time of visits by cosmonauts from other countries. In a response to the NASA selection, in 1976, of non-pilot mission specialist astronauts for upcoming space shuttle missions, the Soviets launched the Inter-Kosmos pro­gram, with the participation of fraternal communist states, initially Bulgaria, Cuba, Czechoslovakia, East Germany, Hungary, Mongolia, Poland, and Romania in joint space flights with the Soviet Union. In 1979 three non-communist nations were added to this list, France, Vietnam, and India, and all of these flights would be carried out between 1978 and 1983. This agreement led in 1985 to an expansion of the program to all countries, communist or not, organized by GlavKosmos. This led to countries such as Afghanistan, Austria, Japan, and the United Kingdom agreeing to manned space flights with the Soviet Union. All of this, however, lay in the future, for now the first guest cosmonauts were training to fly on board Salyut 6.

Operations did not start well with the launch of Soyuz 25, which unfortunately could not dock with Salyut 6, probably due to a fault in the Soyuz docking system, and had to return to Earth. This resulted in an upheaval in the schedule, as this first crew had been due to occupy the station for about two months, during which time they would receive the first on-orbit visitors, and also oversee the docking of the first Progress cargo vehicle. This failure forced mission planners to attempt a winter launch, which, for safety reasons, they were not generally keen on. However, Soyuz 26 was launched on 10 December 1977 and docked, this time with the rear port, successfully a day later. This mission would set the pattern for all future space station operations to follow. The crew of Yuri Romanenko and Georgi Grechko remained on the station for a record breaking 96 days. In view of the failure of Soyuz 25 to dock, they carried out an EVA to check the front docking port, during which they found nothing out of the ordinary. They received their first visitors when the crew of Soyuz 27, Vladimir Dzhanibekov and Oleg Makarov, docked to the front port and formed the first four-man crew in history. Dzhanibekov and Makarov departed on 16 January 1978 after a six-day visit, taking the older Soyuz 26 home and leaving the rear docking port available for the first Progress cargo spacecraft. The final com­ponent of modern space station operations was completed with the launch, on 20 January, of the first Progress cargo spacecraft. This docked at the rear port of Salyut 6 two days later. It was relieved of its cargo and loaded with unneeded equipment, rubbish etc., and then pumped fuel into the Salyut’s propulsion tanks. It undocked from the station on 6 February, tested its back-up rendezvous system, and re-entered the Earth’s atmosphere two days later. Again, this would become a standard proce­dure for future space station operations, continuing today with the ISS. This procedure will not change until the ESA’s ATV cargo craft starts operations in 2007.

The second crew of visiting cosmonauts on board Soyuz 28 docked with the rear port on 3 March. Alexei Gubarev was accompanied by the first international Inter – Kosmos cosmonaut, Vladimir Remek from Czechoslovakia. The visitors undocked from the rear port after a flight of nearly eight days, this time in the same Soyuz they had launched in, and landed safely. Soyuz 27 undocked from the front port on 16 March with Romanenko and Grechko aboard. Their flight, which had surpassed the record set by the final U. S. Skylab crew of 84 days, had been a tremendous success;

they had proved every aspect of space station operations and set the path for all future long-duration expeditions.

The second main expedition to Salyut 6 was undertaken by the Soyuz 29 crew of Vladimir Kovalyonok and Alexandr Ivanchenkov. They launched on 15 June 1978, and docked with the front port the next day. They were to receive two Inter-Kosmos crews, one with a cosmonaut from Poland and the other from East Germany, unload and repack three Progress cargo craft, make an EVA to retrieve material samples from the hull of Salyut 6, and swap the newer Soyuz 31 from the rear port to the front port in order to clear the rear for future Progress dockings. They returned to Earth on 2 November after further extending the duration record to 140 days.

Unfortunately, things would not go quite as smoothly for the third expedition. Vladimir Lyakhov and Valery Ryumin on board Soyuz 32 launched successfully on 25 February 1979, and docked with the front port the next day as per normal. They were expecting to stay for about six and a half months, and apart from working to try

and fix a small leak in one of Salyut’s propellant tanks the mission was preceding as planned. Their first visitors were not so lucky. Soyuz 33 as usual contained an international crew with the guest cosmonaut from Bulgaria, but when they got within range of the station the main engine on their Soyuz misfired, and the docking was aborted. The bitterly disappointed crew made a manual re-entry the next day. This had implications for the long-duration crew. What would happen if their ferry was similarly afflicted? Even if it were not, it would need to be replaced before they could come home; the crew of Soyuz 34 had been due to bring them a new ferry and go home in the older one, but this was now in doubt. In the end it was decided to launch Soyuz 34 unmanned, and use the docked Soyuz 32 to return some samples and experiment results to Earth, also unmanned. The crew then swapped Soyuz 34 to the front port to again allow Progress dockings. The dramas for the resident crew were not yet over. The 10 m diameter KRT-10 radio telescope antenna, which had been deployed from the rear port, became entangled with a fixture on the hull when the crew attempted to jettison it. Therefore, on 15 August, the crew ventured outside to cut the antenna free, doing so with little difficulty. While outside, they and also retrieved sample cassettes from the hull of the station. On 19 August 1979, the crew climbed aboard Soyuz 34 and came home having spent 175 days on board Salyut 6.

Remarkably, the crew for the fourth expedition consisted of Leonid Popov and, making two flights in a row, Valery Ryumin. Ryumin was a last minute replacement for Valentin Lebedev, who had injured a knee shortly before launch. So it was that Ryumin found himself back on board Salyut 6 on 10 April 1980 reading the note that he had left for the next long-duration crew! In contrast to the previous mission, this crew entertained four visiting crews, three Inter-Kosmos and one carrying out the first manned test of the new Soyuz-T spacecraft. On 11 October the main expedition landed safely back on Earth after a mission lasting a record breaking 185 days. This meant that Ryumin had spent 360 days in space, making him the most traveled cosmonaut or astronaut at that time. He would fly again, but not until 1998, and on board a U. S. space shuttle to visit a Russian space station, a joint mission that would never have been predicted in the cold war days of 1980.

The final expedition to Salyut 6 began on 12 March 1981 when Soyuz-T 4 was launched with the crew of Vladimir Kovalyonok and Viktor Savinikh. This was after Soyuz-T 3 had flown a short three-man mission to the vacant station, both to replace some of the systems of Salyut 6, and to verify the three-man capability of the new Soyuz-T. The main expedition was to last for 74 days and receive two visiting Interkosmos crews, both using the older Soyuz spacecraft. The main expedition undocked and landed on 26 May 1981, closing the chapter on the fantastically

successful Salyut 6 station. Later that same year, Cosmos 1267, which had been in orbit since April, docked with the forward port. This helped to prove to engineers the concept of expanding future stations with separately launched modules. Cosmos 1267 was, in fact, a remnant of the Almaz program, as it was one of Vladimir Chelomei’s TKS designs that had been launched on an autonomous mission lasting 57 days before it docked with Salyut 6.

Salyut 6 had been occupied by five long-duration crews for a total of 684 days; it had also been visited 11 times by short-duration crews, 9 of which carried inter­national crewmembers. Salyut 6 was finally de-orbited on 29 July 1982 after four years and ten months in Earth orbit.

Sergei Korolev was the Chief Designer for the Soviet space program, although his identity did not become public until after his death in 1966. He was head of the OKB-1 design bureau that is now known as RKK Energia. In I960 he made the first of many attempts to get the Soviet government to fund a manned space station as a logical progression of the fledgling manned spaceflight program.

On 23 June 1960 Korolev wrote to the Ministry of Defense in an effort to obtain support for a military Orbital Station (OS), on which a decision had been deferred to the end of the year. The station would have a crew of 3-5 and orbit at 350-400 km altitude. Its role would be to conduct military reconnaissance, control other space­craft in orbit, and undertake basic space research. The first version of the station would have a mass of 25-30 tonnes and the second version 60-70 tonnes. Korolev pointed out that his design bureau had already completed a draft project in which 14 work brigades had participated, and so had a detailed plan.

Salyut 6 had been an impressive step forward in space station technology and operations. Salyut 7 was the back-up to Salyut 6 and, therefore, similar in design, but it did have improved systems, and extra comforts for the crews that were likely to be aboard for much longer periods than previously. Personal selection of food items was allowed for the first time, and there was a small refrigerator for the fresh food delivered by Progress. Extra storage was provided, but it would prove to be still not enough as the life of the station lengthened.

Launched on 19 April 1982, Salyut 7 was to have a long life and more resident crews than Salyut 6. The introduction of the updated Soyuz-T spacecraft would allow more flexibility in crew visits owing to its ability to spend more time in space. It was also hoped to achieve the first operational rotation of crews, with a new crew arriving and having the station handed over to them before the old resident crew left. This would save considerable time and resources, as it meant that the station would not have to be powered down and up again by subsequent crews.

Soyuz-T 5 was launched on 13 May 1982 with the first resident crew of Valentin Lebedev and Anatoli Berezovoi—this was defined as the EO-1 crew. They were initially given light duties for their first few days in orbit as they worked their way through the tasks required to commission the new station. New experiments were set up, and the crew slowly settled into a daily routine as they awaited their first visitors. Soyuz-T 6 was launched just over a month later, and carried the first crewmember from outside the Inter-Kosmos organization, Frenchman Jean-Loup Chretien, who was to carry out a series of medical experiments. As did short-term visitors, he wore himself out, shortening his sleep periods to maximize his time in orbit, and by the time Soyuz-T 6 undocked from Salyut 7 to return to Earth, he was exhausted. However, the resident crew of Lebedev and Berezovoi were just as tired, because hosting visitors was hard work, as previous crews had found, and ground controllers gave them a few days off to allow them time to recover. In addition, the two men did not really get on that well; they had not bonded during training for the mission, but for some reason

they had not been reassigned to separate missions. Two men aboard a small space station is never going to be an easy period of time to get through, particularly when it is for such a long period of time, but this pair seemed to exploit every excuse for arguing with one another, even over trivial things. The only break for the crew came

when visitors arrived, and the next set of visitors would be more welcome than most, because it included a woman.

Soyuz-T 7 established another space triumph of sorts for the Soviets. Svetlana Savitskaya was the second woman in space after Valentina Tereshkova in 1963. It was obviously no coincidence that NASA had announced earlier in 1982 that Sally Ride would fly on board the space shuttle’s seventh mission. The Soviets wished to trump NASA’s latest public relations scoop, and assigned Savitskaya to the flight at relatively short notice. However, it is unlikely that the more liberal American Sally Ride would have accepted the flowers and floral apron that were presented to Savitskaya by her male colleagues. Her flight was relatively short, lasting only seven days before the visitors returned to Earth in the older Soyuz-T 5, leaving Soyuz-T 7 for the long-duration crew.

Alone again, the two men struggled to get along; there was a momentary panic when Berezovoi felt unwell one day during an exercise period. His illness threatened the length of the mission, and both men felt angry that having put up with each other for all this time, they might have to come home early. Ground controllers recom­mended that Berezovoi be given an injection of atropine to ease the pain, and this helped, causing him to feel much better by the next day; the mission could continue. Finally the crew had reached their personal limits, and they were allowed to return home. They had set a new endurance record of 211 days, but their landing and recovery did not go completely smoothly, as they had to spend the night on board a disabled, and cold, helicopter. This was the last straw for the two men, and in the twenty odd years since their joint flight, they have barely spoken to each other.

The launch of Soyuz-T 8 on the 20 April 1983 did not go entirely to plan. The crew of Aleksandr Serebrov, Gennady Strekalov, and Vladimir Titov were unable to dock with Salyut 7 because one of the spacecraft’s rendezvous antennas was damaged at launch; they returned to Earth on the 22 April. Soyuz-T 9 docked with the station on the 28 June carrying Vladimir Lyakhov and Aleksandr Aleksandrov. As the next long-duration crew, EO-2, they were due to receive visitors, but unfortunately the launch of Soyuz-T 10-A, again crewed by Strekalov and Titov, was aborted and the launch escape system used when the booster caught fire during the last moments of the countdown. Thus, Strekalov and Titov failed for the second time that year to get to Salyut 7, where they were supposed to add solar arrays to the station. This task would now fall to the resident crew. Following on from the success of Cosmos 1267 with Salyut 6, Cosmos 1443 had docked with the station prior to the arrival of the Soyuz-T 9 crew, and was loaded with 3.5 tonnes of supplies. During its stay, Cosmos 1443 was used to provide attitude control for the station, and to boost Salyut 7’s orbit. The re-entry module would later turn up at a Southerby’s auction in 1993. The crew set about unloading just after they arrived; they then loaded the TKS’ re-entry module with experiment results, which returned to Earth in August. They carried out the spacewalks to install the solar panels (which were cargo in the large module) just a few weeks before their return to Earth on 23 November, after 150 days in space, having received no visitors. At around this time it was noticed by the resident crew, and ground controllers, that Salyut 7 was leaking fuel from its propellant tanks, severely limiting the station’s maneuvrability. Plans were made for the next crew to attempt to fix the problem, rather than abandon Salyut 7 at this early stage.

The TOSZ—Heavy Orbital Station of the Earth—was Korolev’s 1961 project for a large military space station. The draft project was completed on 3 May 1961, and marked the beginning of a long struggle throughout the 1960s to get such a station built and launched. Such a station required, of course, the N-1 rocket, the only rocket with anything like the payload lifting capacity required for such a large and heavy object.

1961— THE OS-1—SERGEI KOROLEV

Work on the OS-1 began on 25 September 1962. Following a meeting between President Nikita Khrushchev and the chief designers at Pitsunda, Khrushchev ordered that a 75-tonne manned platform with nuclear weapons be placed into low-Earth orbit (dubbed elsewhere as “Battlestar Khrushchev’’). Korolev was authorized to proceed immediately to upgrade the three-stage N-1 vehicle to a maximum 75-tonne payload in order to launch the station. By 1965 the mock-up of the huge station had been completed. By 1969 the OS-1 had evolved to this configuration, as described in the official RKK Energia history. In 1991 engineers from Energia and other design bureaus taught a course on “Russian Manned Space” at the Massachusetts Institute of Technology (MIT). Dr. Vladimir Karrask, the first chief designer for the UR-500 (Proton), told of a shroud that he designed for the N-1. The shroud was cylindrical—6 m diameter x 30 m long—with a very “Proton-like” blunt conical top. He indicated that it had flown on the N-1. Another engineer, S. K. Shaevich, stated that flight hardware (including a back-up) was ready for the N-1 flights. There are those who believe that the last two N-1 flights had the Karrask shroud, and possibly the OS-1 station. It is not known if any OS-1 stations actually reached any stage of completion. Although plans for the OS-1 had to be constantly deferred until the N-1 booster proved itself, this did not prevent the design team from undertaking an even more grandiose study—the MKBS—in which OS-1 derived modules would form mere subunits of a huge space complex. At any rate the termination of the N-1 launch vehicle program ended any possibility of launching the station—unless it was reincarnated as the “Mir 2” jumbo space station that was planned for launch by the Energia booster in the 1990s.

Having deciding to concentrate on the space shuttle program after the three visits to Skylab NASA lacked a space station of its own. However, in collaboration with the European Space Agency (ESA), NASA developed the Spacelab. This made available a pick and mix of a pressurized module and open pallets that sat in the shuttle payload bay to allow scientific experiments for the duration of a shuttle mission. It was obviously nowhere near as good as the long-duration experiments that could be carried out aboard the Salyut stations, but it was the closest thing possible with the space shuttle. Critics pointed out that it was impossible to make the shuttle a com­pletely gravity-free environment, as the movements of the relatively large crew, plus thrusters firings, would interfere with the results of many experiments. The project began in 1973 when NASA and ESA signed an agreement that outlined the com­ponents and responsibilities of the Spacelab project. The first engineering model of a pallet arrived at NASA in 1980, and went on to be used on the shuttle’s second flight in 1981. Most Spacelab missions could only last up to 10 days, but NASA added the Extended Duration Orbiter (EDO) pallet to the shuttle and in 1992 STS-50, a Space – lab mission on Columbia, flew a 13-day mission. The longest shuttle mission, STS-80

lasted for almost 18 days, and this represented the limit of the shuttle’s duration. In total twenty-four Spacelab missions would be flown on the shuttle, seventeen of them with the pressurized lab module, the first of which, STS-9, was launched on 28 November 1983 and lasted for 10 days.

Whilst not strictly speaking a space station component, Spacelab did shape the way NASA planned and undertook its science based missions. The crew’s schedule for these missions was extremely tight, with not a minute wasted; of course on a short mission with around the clock shifts of crew members it is acceptable and sensible to plan this way, but it would do nothing to help NASA plan for future space station operations, when it simply would not be possible to plan every last minute of the day.

The Soviets made maximum use of their new ferry craft capabilities on the 8 February 1984 with the launch of Soyuz-T 10. This time the crew numbered three due to the inclusion of a physician, Dr. Oleg Atkov, who would monitor the long – duration crew (EO-3) of Leonid Kizim and Vladimir Solovyov during their record attempt. Kizim and Solovyov had been trained for several EVAs to attempt to fix the leaking fuel tanks. Eventually they would carry out a record six spacewalks in their efforts to fix the leaks and add solar arrays to the station. Salyut 7’s future had been assured by the skillful efforts of the cosmonauts and wisdom of the planners on the ground. Two crews of visiting cosmonauts included the first Indian in space Rakesh Sharma, and the return of Svetlana Savitskaya who would make a spacewalk this

time. Savitskaya was accompanied by Buran chief test pilot Igor Volk, who was using this flight to test a home coming Buran pilot’s ability to land his craft on a runway at the end of a long flight. Upon landing on 29 July, Volk immediately flew a MiG fighter to 21 km before landing with dead engines to simulate a Buran landing. The three-man EO-3 crew landed on the 2 October having set a new duration record of 237 days in space, which would be the longest single-crew stay aboard Salyut 7. Vladimir Dzhanibekov, who had commanded the Soyuz-T 12 mission with Savits­kaya and Volk, could not have had any idea that he would be returning to the station in less than a year, or why.

The year 1985 was to be a somewhat more complicated and dramatic year for Salyut 7 and its crews. It began when Mission Control lost all contact with the station on 11 February; it had lost all attitude control and had gone into free drift mode, making it impossible for a Soyuz ferry to automatically dock with the station. The crew of Soyuz-T 13 were dispatched on 6 June with Vladimir Dzhanibekov and Viktor Savinykh to try and determine what had gone wrong. When they rendez­voused, the station appeared to be undamaged, although it was clearly without power, there being no lights, and the solar arrays pointing in differing directions. The station was slowly rolling around its long axis, but Dzhanibekov was able to line up the Soyuz with the aid of docking controls that had been installed in the orbital module for just such a purpose. They managed to dock, and entered the dead station; it was dark and cold as it had been completely powered off. By the crews own crude estimate, the interior temperature was about — 10°C, an estimate reached by spitting on the bulkhead and timing how long it took to freeze! Clearly, they would have to wrap up to work in these conditions, and return intermittently to the Soyuz to warm up. To attempt to bring the station back to life, the crew fitted spare batteries, replacing the existing ones that would not charge back up. In the process of this work they discovered a faulty charge sensor. This sensor determined if a battery was full or in need of charging, and it had failed in such a way that the computer thought that all of the batteries were fully charged and stopped trying to charge them; as a result all of the batteries went flat, and the station died. If a crew had been on board, the faulty sensor would have been immediately detected, and replaced well before the station lost all power. Once this sensor was replaced, the task of recharging the batteries began, and the station slowly came back to life. The crew had saved the station, once again proving the value of humans in space, and proving that the Soviets were now very comfortable with repairing their spacecraft, rather than just launching new ones when something went wrong. A fact that they would be keen to underline when failures began to undermine the fledgling partnership with NASA.

Soyuz-T 14 arrived on 18 September with Georgi Grechko, Vladimir Vasyutin, and Aleksandr Volkov aboard. Vasyutin and Volkov had trained with Savinykh as the original long-duration (EO-4) crew, so when Soyuz-T 13 landed on 26 September it left behind the EO-4 crew to begin their mission. Unfortunately, during October Vasyutin became very ill; his temperature was very high (about 40°C), and the ground advised him to rest in the hope that the fever would pass. It did not get any better; in fact he seemed to get worse, and Valeriy Ryumin ordered an immediate end to the mission. In actual fact, it took the crew about a week to prepare the station for autonomous flight and return to Earth, by which time Vasyutin had become very ill indeed. Upon his return he was immediately taken to hospital, where he took a month to recover from what turned out to be a prostate infection. It was an unfortunate end to a promising long-duration mission by Savinykh, who was very disappointed to have missed the duration record. It was also unfortunate for the future of Salyut 7, which had clearly reached the end of its useful life. The rescue mission had also used a Soyuz that was to have been utilized by an all female crew commanded by Svetlana Savitskaya with two flight engineers Yekaterina Ivanova and Yelena Dobrokvashina. After the cancelation of their flight it was hoped that they might fly to Mir, but Savitskaya became pregnant in 1986, and the idea was abandoned. Ivanova and Dobrokvashina were never assigned to another mission, and both left the cosmonaut corps in 1993.

The EO-4 mission was to be the last planned long-duration flight to Salyut 7; its successor Mir had been launched on the 19 February 1986, and it seemed as if Salyut 7’s operational life was over. However, a unique mission was planned that would see the crew of Soyuz-T 15, Leonid Kizim and Vladimir Solovyov, activating the new Mir station, and then flying their Soyuz to dock with Salyut 7 to complete and collect the work not finished by the EO-4 crew. So on 5 May they undocked from Mir after six weeks aboard and transferred to Salyut 7 the next day. After 50 days aboard Salyut 7 they returned to Mir for a further 25 days before returning to Earth on the 16 July after a truly unique mission.

Salyut 7 stayed in orbit until 7 February 1991 when it re-entered the atmosphere and was destroyed. The stage, however, had been set, for Mir was now operational and offered much more flexibility than the previous Salyut stations. The best was yet to come.