Soyuz 33

1971-1975/1976-1980

II. THE SOYUZ PROGRAM

Soviet Manned Space Programs: 1957-80

MANNED MISSIONS TO SALYUT 6: 1977-80

SOYUZ 33: A TENSE INITIATION FOR THE FIRST BULGARIAN COSMONAUT

The first crew scheduled to visit the Soyuz 32 crew on board Salyut 6 was that of Soyuz 33. Launched at 1434 GMT on April 10, 1979, Soyuz 33 (Saturn) carried the crew of Nikolay Rukavishnikov and Geogriy Ivanov, the first Bulgarian cosmonaut. Soviet reports said that the launch took place under the worst conditions of any manned launch, with winds gusting as high as 18 meters per second. (160)

Despite the weather, the launch was nominal, as were the five trajectory corrections required to place the spacecraft into a rendezvous orbit with Salyut 6. The approach to the space station began at 1854 GMT on April 11, but as Moscow Domestic Service reported: "During the process of approach deviations occurred in the normal operation of the approach correcting motors of the craft Soyuz 33 and the docking of the craft with the Salyut 6 station was aborted." (161)

As explained later by the crew, the main engine of the Soyuz had failed to fire correctly during its last maneuver prior to docking. The engine should have fired for 6 seconds, but shut itself off after only 3 seconds, and the thrust was uneven. Rukavishnikov commented that the ship had started shaking "I extended my hand and 'calmed' the control panel, holding on to it a little." He said that at that point he thought the control system was malfunctioning, not the engine. (162)

After consulting with the ground, the Soyuz 33 crew tried to fire the engine again, but it shut itself down immediately. The crew was then told to discontinue operations and await further instructions.

Meanwhile, Ryumin reported from the space station that he had noticed an unusual lateral glow from the engines. After one orbit, the Soyuz 33 crew asked permission to try one more time, but ground controllers said no, that the docking was to be aborted and the crew should try to get some sleep.

Telemetry confirmed that the engine had shut itself off because the pressure sensor in the combustion chamber had been activated, indicating that the malfunction was serious. The backup engine on Soyuz was not suitable for rendezvous operations since it was designed for only a single burn at full thrust. Similarly, the docking engines were too small for the maneuver.

Rukavishnikov admitted that he could not sleep, and his mind wandered to Martin Caidin's book "Trapped in Orbit." (163) Not only was he concerned about the main engine, but if the glow noticed by Ryumin had hit the side of the spacecraft, it might have damaged the backup engine as well.

Both the space and ground crews considered the options. The crew would have to make a direct descent from their 346x298 km orbit using a single burn of the backup engine. Nominal burn time would be 188 seconds. If the engine burned for less than 188 seconds but more than 90 seconds, an additional manual engine burn could be made, but the landing spot could not be accurately predicted. If the engine burned for less than 90 seconds, "the vehicle would remain in orbit. Then . . . then there would be new possibilities." (164)

Another option was to use the Salyut engines to bring the space station and the Soyuz closer together, and then use the Soyuz docking engines, which presumably were still operational, to dock the two ships. Such a maneuver would require time-consuming ballistic computations, however, and the ships were separating at the rate of 100 km per hour, so it was rejected. (165)

Ivanvov tried to lighten the atmosphere in the spacecraft and suggested the two of them eat to divert their minds from the problems at hand. Rukavishnikov revealed that they decided to open a gift they had brought for the Soyuz 32 crew. "We opened the hand-some red box tied with a multicolored ribbon and fortified our-selves. I had very little, Georgiy took a good drink." (166)

At 1547 GMT on April 12 the Soyuz 33 crew activated the backup engine. It fired

for the full 188 seconds, but then did not cut off. After another 25 seconds, Rukavishnikov shut it down manually. The crew landed at 1635 GMT (local nighttime), 320 km southeast of Dzhezkazgan. Recovery teams saw the glow of the spacecraft as it reentered the atmosphere, so were able to locate it fairly rapidly once it landed.

The Soviets hailed the second successful ballistic reentry of Soyuz (the first having been the April 5 Anomaly in 1975 when the third stage of the A-2 did not function correctly and the mission was aborted prior to reaching orbit). The crew sustained G-forces of 8 to 10 G, compared with the 3 to 4 G encountered in a nominal Soyuz reentry.

Spacecraft designers were bewildered by what could have gone wrong. The engine had been fired 4,000 times in space and on Earth without failure, and the one part that was finally identified as causing the problem had been tested 8,000 times (the part itself was not specified.) (167)

With the Soyuz 33 crew safely home, mission planners turned their attention to Soyuz 32, which was docked with Salyut 6. They were concerned because the engine on that spacecraft had come from the same lot as the one on Soyuz 33. Thus, they decided to

modify the engine and launch an unmanned test. If the test spacecraft worked, then it would replace Soyuz 32. Thus the Soyuz 34 mission was scheduled.

References:

A. SOVIET SPACE PROGRAMS: 1976-80, (WITH SUPPLEMENTARY DATA THROUGH 1983) MANNED SPACE PROGRAMS AND SPACE LIFE SCIENCES PREPARED AT THE REQUEST OF HON. BOB PACKWOOD, Chairman, COMMITTEE ON COMMERCE, SCIENCE, AND TRANSPORTATION UNITED STATES SENATE, Part 2, OCTOBER 1984, Printed for the use of the Committee on Commerce, Science, and Transportation, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, D. C., 1984

160. Tass, 0905 GMT, 11 Apr. 79.

161. Moscow Domestic Service, 0300 GMT, 12 Apr 79

162. Pravda, 29 Apr. 79, p.4.

163. This is apparently a reference to the book "Marooned," which may have had a different title for the translation Rukavishnikov read.

164. Krasnaya Zvezda, Apr. 2, 1983, p. 4.

165. Ibid.

166. Alcoholic beverages are strictly prohibited in space, even though the implication of this passage is that this was something other than orange juice.

167. Moscow Domestic Service, 2000 GMT, 6 June 79