MIRNEWS.465 10 AUGUST 1999 Computerfailure on board MIR-spacestation: During a radio-amateur conversation on 30.07.99 at 1450UTC (orb. 76824) Haignere said that they had a minor problem with the attitude control of the station, but that all was well and he expected that the problem would soon be solved. During the pass in orb. 76825 (1627UTC) TsUP gave Afanasyev computer commands related to the correction of the attitude with the use of steering rockets and the VDU-thruster, and in that way restoring the efficiency of the solar batteries. One orbit later (76826) at 1935UTC TsUP told Avdeyev that he could use the means of the 'ship' (S-TM29) to secure the power supply. The cause of the computer failure was a wrong command from TsUP. The crew was not very impressed and apart from the operation to restore the functioning of the gyrodynes, they continued a number of experiments and Haignere remained busy with his radio-amateur passion. TsUP altered the working schedule for the next days, using the interruption in the functioning of the attitude control to put forward the integration of the new control and navigation system (BUPO) in the Propulsion Control System of the complex. To make this integration possible, much of propulsion system had to be switched off, and so this 'failure' was utilised in a positive way. BUPO: This is the Russian abbreviation for the new control unit. The name is Unit for Control, Docking and Orientation (Blok Upravleniya Prichalivaniya i Orientatsii). As far as I could derive from radio traffic, they concluded this work already on 31.07.99. On 2.08.1999 the crew conducted tests of the new system. That day the gyrodynes were spinning again at full speed. It always lasts some time to gather the necessary details to know how a new system works. Several news bulletins gave the impression that the BUPO replaced the old central computer TsVM-1. But this computer, and also the SUD (movements control system), which controls the functioning of the gyrodynes, are still operational. BUPO has to secure a safe flight when the station has no crew on board. According to the modest information at my disposal at this point, BUPO can replace the crew when the attitude control by gyrodynes fails. Thusfar the crew used to take over that control by commanding steering rockets and the VDU roll control thruster, thus restoring the attitude and the correct angles of the solar batteries towards the sun. One of the first actions of the crew when the normal attitude control fails, has been the switching off of all energy consuming systems. BUPO should be able to do that when there is no crew on board. The 'P' is an indication that this system will enable TsUP to control approach and docking operations. It stands for 'mooring' or 'docking' (Prichalivaniye). This might mean that BUPO can replace the crew when during docking operations, the automatic Kurs system fails. In the beginning of the year 2000 such an operation has to be executed. Then the 'tanker' Progress-M43, containing 4 fuel tanks, has to be docked at MIR for the final operation: giving the impuls to put the MIR-complex on a destruction course into the atmosphere. So if the Russians can not find the funds to send an extra crew (eventual Mir's Main expedition nr. 28, by Soyuz-TM30), TsUP might via BUPO secure the docking of the tanker. MIR-routine: The cosmonauts energetically continue to execute experiments. If you did not know better, you might get the impression that MIR's exploitation would still last for a long time. Haignere does all what is necessary to conclude the Perseus program, he still executes experiments like Alice-2 and Genesis. A few days ago Avdeyev installed equipment for the execution of the experiment Volna for the study of the efficiency of capillary intake gadgets in fuel tanks. Afanasyev worked on an experiment named Linza. Apart from these technological experiments the normal series were mentioned, giving all kinds of spectrometers and other devices the opportunity to sing their swan song. But the fact that the crew will leave the space station before long more and more emerges in the radiotraffic. The crew already is training in the Chibis suit, always a standard training for crews about to return to earth and they undergo extra medical checks, especially of the cardio- vascular system. Meanwhile they are replacing equipment, for instance a few days ago some accumulator batteries. During radio-amateur conversations Haignere told that they have to do a lot of work during the last weeks of their mission. One of the main tasks is to prevent that an eventual extra crew will arrive in a chaos. They will load all waste, especially human waste and garbage, in the Progress-M42 and they will have to prepare all on board systems for the flight of MIR in the unmanned status. He also spoke about the extra exercises they have to do to be ready to meet the earthly gravity conditions. Communications: During the last weeks the radiotraffic is very dense. The crew regularly uses 2 different channels: 143.625 and 130.165 mc. Via one channel they speak with TsUP, via the other channel they exchange Packet Radio traffic or hold a second conversation. The transceiver for radio-amateur traffic is almost always red-hot, especially when Haignere is using it. He continues to express his displeasure about the lack of discipline among radio-amateurs who fail to listen before calling. If the dense working schedule of the cosmonauts makes this possible, there will be a lot of radio-amateur activities during the last 2 weekends, possibly also with SSTV images. Eventual extra expedition next year: Optimists are sure that such a mission will take place. If so this will be the 28th Main Expedition to MIR, the crew of which will fly to MIR on the Soyuz-TM30. The members of the present crew are not optimistic: Avdeyev and Haignere are not sure that such a mission is possible. At TsUP there is some hope, but the most used expression there is: 'ne veroyatno' (unlikely). For Russia another mission is more important. Nowadays 2 crews are training for a flight to the International Space Station in December 1999 to be there when the Service Module (Zvezda) will arrive there. That crew must be there for the eventual manual docking of Zvezda if the automatic mode fails. The first crew consists of Padalka and Budarin, the stand-in crew of Korzun and Treshchov. The return flight of the present and probably last crew with the S-TM29 is scheduled for 28.08.1999. Regretfully this decision is irreversible. Chris van den Berg, NL-9165/A-UK3202.