|Mission duration||2 days, 6 minutes, 35 seconds|
|Spacecraft type||Soyuz 7K-T/A9|
|Launch mass||6,760 kilograms (14,900 lb)|
|Callsign||Радон (Radon - "Radon")|
|Start of mission|
|Launch date||October 14, 1976, 17:39:18UTC|
|Launch site||Baikonur 1/5|
|End of mission|
|Landing date||October 16, 1976, 17:45:53UTC|
|Landing site||Lake Tengiz|
|Perigee||239 kilometres (149 mi)|
|Apogee||269 kilometres (167 mi)|
Soyuz 23 (Russian: Союз 23, Union 23) was a 1976 Soviet manned space flight, the second to the Salyut 5 space station. Cosmonauts Vyacheslav Zudov and Valery Rozhdestvensky arrived at the station, but an equipment malfunction did not allow docking and the mission had to be aborted.
The crew returned to earth, but landed on partially frozen Lake Tengiz, the first splashdown in the Soviet space program. While there was no concern about any immediate threat to the crew, the capsule sunk under the surface of the frozen lake, and recovery took nine hours owing to fog and other adverse conditions.
|Flight Engineer||Valery Rozhdestvensky
|Flight Engineer||Yuri Glazkov|
|Flight Engineer||Mikhail Lisun|
Soyuz 23 was launched 14 October 1976 with an estimated 73- to 85-day mission planned aboard the orbiting Salyut 5 space station. Others suggest a 17- to 24-day mission was a more likely intention. It was the first visit to the station after the sudden termination of the Soyuz 21 mission in August. However on 15 October, during the automatic approach phase, the automatic docking system malfunctioned before the craft was within 100 metres of the station. Crews were normally trained for a manual dock, but not for a manual approach. The mission, accordingly, had to be abandoned.
The craft had only two days of battery power, so systems were powered off, including the radio, to conserve power. The day's landing opportunity had already passed, so they had to wait for the next day's landing opportunity near the Baikonur Cosmodrome.
On 16 October, Soyuz 23 returned to earth and landed 8:45 p.m. local time, but weather conditions were poor and the cosmonauts experienced an unusual recovery. They landed on a freezing Lake Tengiz, 8 km from shore, in the middle of a blizzard, with fog and temperatures at −22 °C. It was the first splashdown by a Soviet crew. The capsule was designed to land in any conditions, even in a body of water, so the only concern was the increased difficulty in finding the capsule and crew.
The parachute quickly filled with water and dragged the capsule and its crew beneath the surface. The capsule cooled in the freezing water, and the cosmonauts removed their pressure suits and donned their normal flight suits, expecting a quick rescue.
But the capsule's beacons could not be seen in the heavy fog, and rubber rafts used to try to reach them were blocked by ice and sludge. Amphibious vehicles were air-lifted to the vicinity, but could not reach the capsule owing to bogs surrounding the lake. Accordingly, the rescue was called off until dawn. The cosmonauts were safe, but they were low on power, so they were forced to shut down everything but a small interior light.
The next morning, frogmen were dropped in by helicopters, attached flotation devices to the Soyuz craft and recovered the crew. The capsule was too heavy to be lifted by the helicopter, so it was dragged to shore. The recovery operation had taken nine hours.
- Mass: 6,760 kg (14,900 lb)
- Perigee: 239 km (149 mi)
- Apogee: 269 km (167 mi)
- Inclination: 51.6°
- Period: 89.5 min
- "Baikonur LC1". Encyclopedia Astronautica. Retrieved 2009-03-04.
- The mission report is available here: http://www.spacefacts.de/mission/english/soyuz-23.htm
- Newkirk, Dennis (1990). Almanac of Soviet Manned Space Flight. Houston, Texas: Gulf Publishing Company. ISBN 0-87201-848-2.
- Clark, Phillip (1988). The Soviet Manned Space Program. New York: Orion Books, a division of Crown Publishers, Inc. ISBN 0-517-56954-X.