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Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 10/97 WHAT IS HAPPENING WITH MIR? by Wolfdietrich Hoeveler Since February, the cosmonauts onboard MIR have not had a break in the action: fire on board, failure of several systems, collision of the transport spacecraft Progress M-34 with the space station, continuous difficulties in docking of Sojus or Progress capsules. In the boulevard press, the Russian space station is already often called a "junkpile in space". Quite a few people in the USA and Europe are asking the question: what is the matter up there? The western experts agree: There is no reason to call MIR a "junkpile". For Dr. Hans Stromeyer, project manager of the DLR (German Aerospace Research Establishment) during the German MIR '97 mission, "MIR is still an excellent platform to prepare for the International Space Station". He continues, saying that ISS will not be spared from mishaps either. MIR has already been operating five years more than its projected service-time. The basis module was launched on February 2, 1986. The station has been continuously expanded since then. Following the basis module, which includes the central supply installations such as washing room and kitchen, Kvant 1 was docked on to the station in 1987. Kvant 1 contains part of the position control system, along with astrophysical instruments. Kvant 2 followed in 1989 and was coupled in a right angle to the docking node on the basis module. This module contains the air lock for EVAs (extra-vehicular activities), along with instruments for earth surveillance and biological research. In 1990, Kristall followed which was coupled opposite to Kvant 2 at the basis module. Since then, biological and material scientific research has been done in this module. In 1995, Kristall was fitted with a docking point for the American Space Shuttle and, was moved to today's position on the station to make room for the Spektr module which took Kristall's earlier position in 1995. From the beginning, Spektr was jointly used by the USA and Russia. Scientific instruments from both countries are in service for earth surveillance, earth surface studies, as well as, for monitoring the exposure of the station to X-ray and Gamma radiation. As the last module, Priroda was connected in 1996 at the node, opposite to Kristall. Priroda is the first international initiative for creating a global surveillance and prognosis system of anthropological effects on the environment. With the additional modules, all of MIR's docking ports are permanently occupied, except for two which are needed for the space capsules that carry the crews to the station and ensure the supply of air, water, food, fuel, and spare parts. The respectively older Sojus-TM capsule is permanently docked to the docking hub. With this capsule, the old crew flies back to earth after a one to two week changeover time. The newer capsule, that has carried the new crew, is first docked to the basis module. During this time, the unmanned space transporter Progress M follows the station. Once the old crew has returned to earth with their capsule, the new crew disconnects their Sojus TM from the basis module and couples it to the docking node. After that, Progress is docked to the basis MIR module. This ensures a quick access to the Sojus capsule in case of an emergency, while Progress can be used as some kind of a storage room. The Progress and Sojus capsules are docked either with the Ukrainian developed Kurs system or manually with the Torus system. The Kurs system is equipped with radio sensors and is computer controlled. It is said to be very accurate - if it works. The manual Torus system requires sensitive control inputs from the station commander since a camera in the Progress vehicle is the only help for docking. There are no reliable numbers concerning the relative speed of the capsule available. During the entire docking phase, the station continues its flight which is stabilized through gyro systems. Should these gyros fail, numerous control nozzles take over the stabilization as a back-up. So much for the basic docking procedures. The spring of 1997 began uneventful until a fire on board made the headlines. It was serious but not life-threatening. At least, the international public's attention was directed to MIR now. Still, it came worse. On June 25, 1997, station commander Vasily Tsibliyev was to practice the manual docking without the Kurs system since, due to the known budget problems in Russia, the Kurs system is not in a desirable condition. It looks like the cosmonauts will not use it in the future and continue with the manual docking procedures. Tsibliyev released the overloaded Progress capsule and let it fly towards the Kvant-1 module which is the standard docking point for the capsule. However, during this critical test the spacecraft had gained high speed and obviously approached the station from the side. Experts are talking about a speed of 3 m/sec instead of the usual 5 to 10 cm/sec. The station commander had no choice but to direct the transporter to fly underneath the station in order to avoid a deadly crash. Due to the limited view, this maneuver failed. Progress touched the basis module and collided with a solar generator from the Spektr module. The transporter was out of control for a limited time. Due to further mishaps and the overload of the crew, the repair had to be delayed until August. On 7 August, the new crew, Anatoly Solovyov and Pawel Vinogradov, were to replace the exhausted crew. Michael Foale stayed on board and will be replaced by David Wolf in October. However, even the new crew was not spared with mishaps. On 18 August, the crew released the Sojus capsule and circled the station to find out more about the damage. It only determined damage to the Spektr's solar generators. A crack in the Spektr module could not be detected and since then, the experts are talking about a crack in the mounting of the solar generator. According to the rate of pressure loss, the crack is estimated to have a length of 1,5 cm. When, after docking Sojus to the docking node the crew wanted to couple the free-flying Progress capsule to the Kvant-1 module, the on-board computer responsible for stabilizing the MIR's position failed. The station began slowly to move away from Progress. Solowjow had no choice but to switch over to manual steering with the Torus system. After replacing the respective part of the computer, the system was booted again and, following an exhausting manual input of the parameter data, the system continued to run flawless. With this, the requirements for the difficult repairs of the station were given, which are necessary to restore the full energy supply. Since the station currently has only 50 percent of its energy supply available, no experiments can currently be accomplished. Only after extensive repairs (for the first time a leakage in a space ship is repaired from the outside) the Spektr module might eventually become serviceable again, allowing the MIR to be a platform for experiments before the International Space Station is fully operational in 2003. From page 40 of FLUG REVUE 10/97 Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 10/97 Copyright 1997 by Motor-Presse Stuttgart. All rights reserved. Last updated September 5, 1997 FLUG REVUE, Ubierstr. 83, 53173 Bonn, Germany