Outposts on the Frontier: A Fifty-Year History of Space Stations (Outward Odyssey: A People's History of Spaceflight)
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Without the Soyuz orbital module, Lyakhov and Mohmand would have to spend almost twenty-four hours in orbit wearing their Sokol pressure suits. They couldn’t stretch out since the orbital module had already been jettisoned. Plus, the spacecraft’s toilet was aboard the orbital module as well. So they pretty much had to sit cramped in the fetal position in a slightly cold Soyuz descent module with no fresh food and no toilet while awaiting the next deorbit window. Analysis of telemetry from the craft’s Argon computer revealed that it had selected the wrong program for its engine firing and that the engine itself was okay. Sure enough, the engine fired properly the next day, and the crew returned home safely.
While Abdul Mohmand was given the usual state medals and hailed as a hero for his flight, he didn’t remain in Afghanistan for long. After the Soviet forces completed their withdrawal in 1989, Afghanistan fell back into a civil war between government forces and rebel factions who had Western support during the Soviet occupation years. The Afghan Communist government fell in 1992, and Mohmand fled to Germany, knowing that his life was in danger if he remained behind, since he was a symbol of Afghanistan’s old regime. He applied for and was granted asylum, eventually becoming a German citizen in 2003.
Going for the Record
With Soyuz TM-5 safely on the ground, the crew got back down to business with Polyakov performing his duties as a doctor and flight engineer in support of Titov and Manarov. Soyuz TM-6 was redocked on the front port, and the next Progress to arrive carried among its cargo the redesigned tool needed to help with replacement of the X-ray detector on Kvant 1. After making preparations to finish the job, Titov and Manarov got down to business during an EVA on 20 October. This time with the new equipment, the crew got the job done ahead of schedule and replaced the faulty detector with a new one. Kvant 1 was fully operational once again.
Dr. Polyakov had the crew on an increased exercise regime to help combat the effects of weightlessness and prepare them for a return to Earth. This did the trick, as Titov and Manarov didn’t seem to suffer from the same weakness problems Romanenko encountered. The two men broke Romanenko’s 326 day record on 12 November and Polyakov gave them a go to spend “a year and a day” in space.
First European Space Walk
A few days after Buran’s successful two-orbit, unmanned flight test in November, Soyuz TM-7 lifted off from Baikonur with Soviet cosmonauts Aleksandr Volkov and space rookie Sergei Krikalev on 28 November. Joining them would be an old visitor, French CNES astronaut Jean-Loup Chrétien, making his second spaceflight. After Chrétien’s first spaceflight, he trained as a NASA payload specialist backup to fellow French astronaut Patrick Baudry for shuttle mission STS-51G, which flew in June of 1985. Chrétien was the first guest cosmonaut to be granted a second spaceflight, and this mission would last almost a month.
This was the first time Mir had hosted six visitors at once, and things were a bit cramped in those days. With only the Kvant 1 module docked to the base block, Mir wasn’t all that much bigger than a standard Salyut, but the crew got down to business in an organized fashion. Chrétien had nearly six hundred kilograms of equipment at his disposal and conducted a full range of technology and medical experiments. This was something unique for the French, given that NASA’s shuttle was only capable of sending somebody up for a little over a week at most. Some of the French experiments tested equipment planned for the ESA Hermes space shuttle program.
The highlight of Chrétien’s visit, though, was an EVA to deploy a French-designed folding truss called the Era structure. It was part of a French study to see if this specific design could be used for a radio antenna on a future spacecraft. Volkov and Chrétien performed the space walk on 9 December. Chrétien also mounted a couple of experiment cassettes on the outside of Mir for exposure, before the two men hooked up the truss to an external power port on Mir’s base block. Once they finished their task, Krikalev, inside Mir, flipped a switch to command the structure to unfurl. It didn’t budge. A few nudges by Chrétien did nothing. Finally, Volkov gave it a few kicks with one of his legs, and the structure unfurled fully. After a few minutes of deployment where sensors on board collected data on the truss to determine how well it worked, it was jettisoned. The space walk took six hours to complete and set a new record. It was also the first space walk ever conducted by a person not of Soviet or U.S. nationality.
Handoff
By 15 December Titov and Manarov had surpassed the previous record by 10 percent, making it an official space record to the International Astronautics Foundation. The handoff went well, with the new crew settling in while the old crew got ready to return home with their French guest. Polyakov would remain in orbit with Volkov and Krikalev to potentially try to set a record on his own. By 21 December, everything was ready for Titov, Manarov, and Chrétien to return home aboard Soyuz TM-6.
After the difficulties encountered by Soyuz TM-5, the deorbit procedures were revised so that the orbital module would not be jettisoned until after retrofire took place. It was a good thing, too, as during the first attempt to perform the deorbit burn, the computer became overloaded and canceled the sequence. After another orbit, the engine fired, and TM-6 began its journey home. Reentry and landing were normal. The recovery forces were on hand to greet the two men who had spent a year in space; while they took time to adjust back to Earth’s gravity, they were no worse off than crews who had flown for a typical six-month Mir expedition. Further medical testing came to the same conclusion, showing that the cosmonauts had not suffered any additional demineralization of their bone structure than someone who had spent half that time in zero gravity. After a few days of physical therapy, which included rehabilitation exercise in a swimming pool to help stimulate muscles made long dormant by weightlessness, the crew were up and walking around in almost no time. The increased exercise regime on orbit seemed to do the job.
New Year, New Challenges
When Volkov and Krikalev joined Polyakov on orbit as part of the Mir EO-4, it was planned for Mir to receive at least one and possibly two new modules to expand the complex in 1989. Both men were trained in the tasks required to activate the new systems. Both modules were built from TKS spacecraft and weighed about twenty tons each, almost as much as the Mir base block. The first module, Kvant 2, was originally planned for flight during Titov and Manarov’s time in orbit, until it experienced delays. This also meant that the launch date for the second module, Kristall, would be delayed as well.
After Chrétien’s return, the Soviets announced that they wouldn’t be offering anymore “free rides” to guest cosmonauts. Future short-duration flights to Mir would require payment of a fee for the services, so most future Soyuz flights in the near term would only have two crewmembers. With the certified design life of six months on orbit for a Soyuz TM module, there wouldn’t be a need for dedicated Soyuz ferry swap missions either. As for future long-duration expeditions, with one pair having successfully set a record of a year in space, there wasn’t really a need to push the envelope any further with a full Mir crew. Future endurance records would be attempted by a single cosmonaut only.
Changes at Energia
During the delay of the next two Mir modules, Energia’s chief designer Valentin Glushko died of natural causes on 10 January 1989. As a member of the first group of chief designers from the old days of the Soviet space program, his loss was a great one. During his tenure at Korolev’s old bureau, Glushko was mostly involved with the development of the LHX-LOX-powered Energia rocket. This was a reversal of his previous stance, as he resisted calls to work on hydrogen-powered rocket engines when Korolev was alive. While the Energia rocket had successfully flown two test flights, including Buran’s launch, there was no money to develop it further. The Soviet Union’s economy was slowly beginning to crumble from the weight of decades of economic stagnation. While the Energia rocket itself would not fly again, its strap-on boosters would form the basis of a very successful satellite launch vehicle called Zenit (a Russian term meaning
“Zenith”).
Glushko had given stability to the bureau, something that many have said it hadn’t had since Korolev’s death. Yuri Semenov, the deputy designer who first came to prominence in his management of the first Salyut station project two decades earlier, became Energia’s next leader. Semenov had spent many years managing the DOS program; since it had become the primary focus of the Soviet manned space efforts, he was considered to be the best man to take the bureau into the next decade.
A Brief Pause
By April of 1989, delays in the development of the Kvant 2 and Kristall modules for Mir meant that they would not be ready to fly by the time the Mir EO-4 was scheduled to return home. One module could perhaps have been launched sooner, and it could have been left docked on Mir’s forward axial docking port, but this meant that the station wouldn’t be able to accept any Progress supply flights with a Soyuz occupying the aft port. The next module would have to be moved to one of the radial docking ports as soon as possible to free up the front port.
The docking of a twenty-ton module to the radial port meant that the station would be L shaped with an asymmetric mass configuration and the center of mass outside of the station’s thrust line. If a reboost burn were conducted, the station would likely end up tumbling end over end. Small orbital maneuvers for stellar or planetary observations would be limited as well due to the strain on the station’s gyrodynes and attitude-control computer. To compensate for this, it was better to dock two modules of the same mass to opposite radial ports, giving the station a T shape. This would give Mir the proper center of mass.
It was decided to bring the Mir EO-4 crew home at their scheduled time, rather than having them wait on orbit for who knew how long. Mir had received several new pieces of scientific apparatus on multiple Progress flights during their stay, but they were useless until the new modules were docked and just took up space inside the station. EO-4’s return without another crew to relieve them meant that Polyakov would have to cut short his attempt at a record. The next expedition would be ready to fly when the next module was.
So the crew loaded up the Soyuz TM-7 with the results of their experiments and returned Mir to automatic flight, undocking from it on 27 April 1989. They performed a successful deorbit and landed the same day, with Volkov and Krikalev having spent 151 days in space. Polyakov’s total was 240 days. While it was planned for Mir to be continuously occupied, the station was still in excellent shape, and no problems were encountered during this unmanned period. The X-ray experiments on Kvant 1 could be operated autonomously from the ground and continued to collect data. All three cosmonauts were none the worse for wear upon their return.
Reoccupation
Prior to the launch of the next Soyuz, a new variant of the Progress craft was launched in late August. This spacecraft, known as Progress M-1, was an updated version of the craft. Like the Soyuz TM series, it contained upgraded systems, which included replacement of the Igla rendezvous system with Kurs. It docked with the front port of Mir two days after launch. Mir’s front port was set up with fuel and water transfer lines, same as the aft port, but it only had the Kurs system and couldn’t guide in Igla-equipped Progress modules. Kurs-equipped Progress-Ms could now replenish the station’s consumables from either end, although the aft port was still preferred so that Progress craft could conduct periodic orbit reboosts. The Progress-M design could also supplement Mir’s electrical power with its own solar arrays while docked.
On 8 September 1989, Soyuz TM-8 lifted off with Mir EO-5 crewmembers Aleksandr Viktorenko and Aleksandr Serebrov. It docked with Mir’s aft port on Kvant 1 two days later. Both cosmonauts were veterans of the Salyut program with extensive experience. They were trained to perform many of the tasks originally assigned to the previous crew, preparing the station for Kvant 2’s arrival.
While the crew got down to business as usual unloading the Progress and conducting experiments, a solar flare in late September added some excitement to the mission, as radiation from the flare set off a detector in the Mir base block. While the levels of radiation weren’t high enough to warrant an immediate evacuation, the crew spent the next few days sleeping in the Kvant 1 module since it was more heavily shielded than the base block or the Soyuz. The Soviets announced that the crew only received a radiation exposure from the flare that was equivalent to two normal weeks in space. Neither Viktorenko nor Serebrov seemed to suffer any ill effects from the encounter.
The Kvant 2 would experience one more delay before its launch as a computer fault was detected during its final checkout. The fault was traced to a batch of computer chips in the Kurs rendezvous-and-docking system. So as a precaution, engineers on the ground opted to replace all the suspect computer chips with newer ones. This would delay Kvant 2’s launch by about forty days from mid-October to late November. The original plans were for the crew to receive the Kristall module in early 1990 before their return home. But with the slip in the schedule, they only received the first module.
Kvant 2 Arrives
The Proton rocket carrying the Kvant 2 finally got airborne on 26 November, and the module entered orbit normally. But a problem was detected during the opening of its solar arrays as one of the arrays would not fully unfurl. The module could still dock with Mir, but it was decided to make an attempt to unfurl the panel before Kvant 2 docked with the station, as an unsecured solar array could cause problems. The array was also needed to deliver critical electrical power to the module both before and after docking. Engineers on the ground commanded the module to begin a slow roll and simultaneously commanded the array’s rotation motor (used normally to track the sun) to move back and forth to try to jostle it. The hope was that centrifugal force and the jostling would coax the panel to open. The process worked, and the panel opened fully.
After six days of free flight on a trajectory set to conserve fuel consumption, the Kvant 2 module became visible to the Mir occupants. The Progress had been jettisoned from the front port a couple of days earlier to prepare for this moment. The Kurs docking system guided the Kvant 2 to within twenty kilometers of Mir before aborting the rendezvous after sensing the approach was too fast. Coincidentally, the station’s Argon computer also went down, knocking out the station’s gyrodynes. The crew got Mir stabilized, and controllers in Kaliningrad revised the approach procedures for the module. Four days later, they tried again. Viktorenko used the thrusters on the Soyuz ferry at the aft port to hold the station’s attitude stable while the Kvant 2 continued its approach. The module made a smooth hard dock on the front axial port with no problems.
The next part was something new. Kvant 2 extended a pivoted, blunt structure known as the Lyappa arm into one of two receptacles on Mir’s front hub. These openings were offset by 45 degrees each from Mir’s vertical axis. The arm and the receptacle resembled a smaller version of a docking probe and drogue. Once the arm was fully seated, the module was lifted out of the axial docking port by the arm and did a half-pivot and half-twist maneuver until it ended up fully seated in the top docking port, 90 degrees offset from the axial port. The operation took an hour to perform.
38. Illustration showing how the Kvant 2 module was moved with its Lyappa arm after docking. Courtesy NASA.
Kvant 2 added some new capabilities to Mir and augmented some of its older equipment. It contained six new gyrodynes to supplement those on the base block and Kvant 1; it featured two additional water storage tanks and an improved water-recycling system. Internally, the module was divided into three compartments, with a new airlock for EVAs being mounted at the far end, a second instrument and cargo compartment in the middle that could also double as an emergency airlock, and an inner compartment that was equipped with a variation of the crew shower first flown on the Salyut stations. The shower proved problematic, though, so later crews turned it into a steam room before it was finally dismantled in the mid-1990s, with crews preferring to take “baths” by wiping themselves down with wet towels and soap containing a biocide. The module also
contained a new main computer designed to replace Mir’s four-year-old Argon 16B system.
Being designed as a multipurpose module, Kvant 2 was loaded with equipment for science gathering. It contained no less than six different spectrometers in various wavelengths and also included a new version of the venerable MKF-6 Earth resources camera system, known as MKF-6MA. Also on board was a bird egg incubator designed to help hatch quail eggs so that cosmonauts could study the development of embryos in zero gravity. Kvant 2 also contained a protein-crystal growth experiment from the American company Payload Systems Incorporated. The company was founded by STS-9 veteran and payload specialist Bryon Lichtenberg. Due to U.S. restrictions on transferring technology to the Soviet Union, this particular experiment was sealed and only had a single power switch.
Some new EVA equipment was also delivered, which included two brand-new, third-generation Orlan-DMA space suits and the YMK (a Russian acronym meaning “Cosmonaut Maneuvering Unit”) jet pack. The YMK was a free-flight pack that worked by firing jets of compressed nitrogen gas to control orientation and translation of the cosmonaut wearing it on a space walk. It was inspired by NASA’s Manned Maneuvering Unit, first tested on shuttle mission STS-41B by astronaut Bruce McCandless. The YMK was larger than the Manned Maneuvering Unit but performed the same functions.