Soyuz 23 (, ''Union 23'') was an October 1976,

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

crewed space flight, the second to the Salyut 5

space station A space station (or orbital station) is a spacecraft which remains orbital spaceflight, in orbit and human spaceflight, hosts humans for extended periods of time. It therefore is an artificial satellite featuring space habitat (facility), habitat ...

. 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 Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

, but landed on partially frozen Lake Tengiz, the first crewed splashdown in the

Soviet space program The Soviet space program () was the state space program of the Soviet Union, active from 1951 until the dissolution of the Soviet Union in 1991. Contrary to its competitors (NASA in the United States, the European Space Agency in Western Euro ...

. While there was no concern about any immediate threat to the crew, the capsule sank under the surface of the frozen lake, and recovery took nine hours owing to fog and other adverse conditions. The landing marked the only example of an unintentional splashdown of a crewed spacecraft as of November 2024.

Crew

Backup crew

Reserve crew

Mission highlights

Soyuz 23 was launched 14 October 1976 with an estimated 73- to 85-day mission planned aboard the orbiting Salyut 5 space station. Other sources 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 Soyuz 21 (, ''Union 21'') was a 1976 Soviet crewed mission to the Salyut 5 space station, the first of three flights to the station. The mission's objectives were mainly military in scope, but included other scientific work. The mission ended ...

mission in August 1976. However, on 15 October 1976, during the automatic approach phase, the automatic docking system malfunctioned before the craft was within 100 metres of the station. Crews were 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 The Baikonur Cosmodrome is a spaceport operated by Russia within Kazakhstan. Located in the Kazakh city of Baikonur, it is the largest operational space launch facility in terms of area. All Russian Human spaceflight, crewed spaceflights are l ...

. On 16 October 1976, Soyuz 23 returned to Earth and landed at 17:45:53 UTC, but weather conditions were poor and the cosmonauts experienced an unusual recovery. They landed on a freezing Lake Tengiz (average depth 2.5 m, max depth 6.7 m), at 8 km from shore, in the middle of a blizzard, with fog and temperatures at −22 °C. It was the first water landing 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 sank beneath water and dragged the capsule and its crew beneath the surface; in addition an electrical short caused by the water impact caused the reserve parachute to accidentally deploy. The capsule cooled in the freezing water, and the cosmonauts removed their pressure suits and donned their normal flight suits, expecting a quick rescue. The parachutes became waterlogged and pulled the capsule onto its side, preventing the hatch from being opened. The transmission antennas were also under water, so the crew could not communicate with rescue teams. 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 airlifted 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 and attached flotation devices to the Soyuz craft. The capsule was too heavy to be lifted by the helicopter, so it was dragged to shore. The recovery operation had taken nine hours. No attempt was made to open the hatch as the recovery crews assumed the cosmonauts were dead, so they called for a special team to remove their bodies. Eventually, eleven hours after splashdown, the capsule was opened, and the crew was found unconsious due to CO₂ accumulation in the submerged and powered down vessel. The cosmonauts were rescued, if badly chilled (the interior of the descent module was coated with frost). Press releases by Soviet news agency TASS announced that there had been a water landing and that the cosmonauts were recovered safely, but made no mention of the rescue operation involved and the details of it were not revealed until the era of glasnost a decade later.

Mission parameters

* Mass: * Perigee: * Apogee: * Inclination: 51.6° * Period: 89.5 minutes

References

External links

Drama on Tengiz Lake
(in Russian) with photos

(in Russian) {{Orbital launches in 1976 Crewed Soyuz missions 1976 in the Soviet Union Spacecraft launched in 1976 Spacecraft launched by Soyuz rockets Spacecraft which reentered in 1976