Soyuz 18a
Encyclopedia
Soyuz 18a (also called
Soyuz 18-1 and the April 5 Anomaly) was a manned Soyuz spacecraft
launched by the Soviet Union
in 1975, intended to dock with the orbiting Salyut 4
space station
, but which failed to achieve orbit due to a serious malfunction during launch. The crew consisted of commander Vasili Lazarev, an Air Force major, and flight engineer Oleg Makarov, a civilian.
The accident was disclosed by the normally secretive Soviets as it occurred during preparations for their joint Apollo-Soyuz Test Project
with the United States
which flew three months later. The crew, who feared initially they had landed in China
, were successfully recovered.
space station for a 60-day mission. Both cosmonauts were on their second mission and had flown their first mission together, Soyuz 12
, in September 1973 to test a new type of Soyuz spacecraft after the fatal accident of Soyuz 11
.
The launch proceeded according to plan until T+288.6 seconds at an altitude of 145 kilometres (90.1 mi), when the second and third stages of the booster began separation. Only three of the six locks holding the stages together released and the third stage's engine ignited with the second stage still attached below it. The third stage's thrust broke the remaining locks, throwing the second stage free but putting the booster under unanticipated strain that caused it to deviate from the proper trajectory. At T+295 seconds, the deviation was detected by the Soyuz's guidance system, which activated an automatic abort program. This separated the Soyuz spacecraft from the third stage booster and then separated the orbital and service modules of the Soyuz from the re-entry capsule.
At the time when the safety system initiated separation the spacecraft was already pointed downward toward Earth, which accelerated its descent significantly. Instead of the expected acceleration in such an emergency situation of 15 g
(147 m/s²), the cosmonauts experienced up to 21.3 g (209 m/s²). Despite very high overloading, the capsule's parachutes opened properly and slowed the craft to a successful landing after a flight of only 21 minutes.
The capsule landed southwest of Gorno-Altaisk at a point 829 kilometres (515 mi) north of the Chinese border. The capsule landed on a snow-covered slope and began rolling downhill towards a 152 m (498.7 ft) sheer drop before it was stopped by the parachutes becoming snagged on vegetation.
Having landed in chest-deep powder snow and a local temperature of -7 °C, the cosmonauts donned their cold-weather survival clothing. Lazarev, fearing they had landed in China, burned papers relating to a military experiment he had been scheduled to perform in space. Soon, the crew was in radio contact with a rescue team in an approaching helicopter, who confirmed their landing point was in the Soviet Union, near the town of Aleysk
. The deep snow, the high altitude, and the terrain meant the rescuers had great difficulty in making contact with the cosmonauts. It was the next day before they were safely air-lifted out. The crew were returned to Star City
; the capsule was recovered some time later.
Initial Soviet reports stated the men had suffered no ill effects from their flight. Vladimir Shatalov
, the Director of Cosmonaut Training, reported they were fit to fly another mission. However, subsequent reports claimed that Lazarev was injured by the high acceleration of re-entry.
In Brezhnev's time it was rare to disclose anything about Soviet failures, and so the first (Soviet) publication about the realities of the flight was not made until 1983 in the Army newspaper "Red Banner". The Americans were informed on April 7 after the crew had been rescued. However, as the failure occurred during preparations for the joint Apollo-Soyuz Test Project
, the Soviets were 'requested' to provide the Americans with a more detailed report. (There was even a U. S. Congressional Inquiry regarding this failure and several others.) It was revealed that the booster used had been an older model than the one planned for use in the joint mission that July. In the report the Soviets made to the Americans, the abort was referred to as "the April 5th anomaly" and as this was the only term the Soviets ever used for the incident, it became the 'official' designation for years afterwards. The mission is referred to in the literature as Soyuz 18-1 or Soyuz 18a, since the following Soyuz mission in May 1975 received the name Soyuz 18
(the Soviets only gave numbers to successful launches).
The Soyuz 18a flight has been the only case of a manned booster accident at high altitude. The exact landing site of the capsule had been a subject of debate amongst space historians in subsequent years. A Russian source quoted by James Oberg
has stated that the landing occurred in Mongolia
. Other sources have claimed that the capsule came down in China, but both it and the crew were recovered before the Chinese authorities became aware of it.
Soyuz 18-1 and the April 5 Anomaly) was a manned Soyuz spacecraft
Soyuz spacecraft
Soyuz , Union) is a series of spacecraft initially designed for the Soviet space programme by the Korolyov Design Bureau in the 1960s, and still in service today...
launched by the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
in 1975, intended to dock with the orbiting Salyut 4
Salyut 4
Salyut 4 was a Salyut space station launched on December 26, 1974 into an orbit with an apogee of 355 km, a perigee of 343 km and an orbital inclination of 51.6 degrees. It was essentially a copy of the DOS 3, and unlike its ill-fated sibling it was a complete success...
space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...
, but which failed to achieve orbit due to a serious malfunction during launch. The crew consisted of commander Vasili Lazarev, an Air Force major, and flight engineer Oleg Makarov, a civilian.
The accident was disclosed by the normally secretive Soviets as it occurred during preparations for their joint Apollo-Soyuz Test Project
Apollo-Soyuz Test Project
-Backup crew:-Crew notes:Jack Swigert had originally been assigned as the command module pilot for the ASTP prime crew, but prior to the official announcement he was removed as punishment for his involvement in the Apollo 15 postage stamp scandal.-Soyuz crew:...
with the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
which flew three months later. The crew, who feared initially they had landed in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, were successfully recovered.
Crew
Backup crew
Mission highlights
Soyuz 18a was intended to be the second mission to take cosmonauts to the Soviet Salyut 4Salyut 4
Salyut 4 was a Salyut space station launched on December 26, 1974 into an orbit with an apogee of 355 km, a perigee of 343 km and an orbital inclination of 51.6 degrees. It was essentially a copy of the DOS 3, and unlike its ill-fated sibling it was a complete success...
space station for a 60-day mission. Both cosmonauts were on their second mission and had flown their first mission together, Soyuz 12
Soyuz 12
Soyuz 12 was a 1973 manned test flight by the Soviet Union of the newly-redesigned Soyuz 7K-T spacecraft that was intended to provide greater crew safety in the wake of the Soyuz 11 tragedy. The flight marked the return of the Soviets to manned space operations after the 1971 accident...
, in September 1973 to test a new type of Soyuz spacecraft after the fatal accident of Soyuz 11
Soyuz 11
Soyuz 11 was the first manned mission to arrive at the world's first space station, Salyut 1. The mission arrived at the space station on June 7, 1971 and departed on June 30, 1971. The mission ended in disaster when the crew capsule depressurized during preparations for re-entry, killing the...
.
The launch proceeded according to plan until T+288.6 seconds at an altitude of 145 kilometres (90.1 mi), when the second and third stages of the booster began separation. Only three of the six locks holding the stages together released and the third stage's engine ignited with the second stage still attached below it. The third stage's thrust broke the remaining locks, throwing the second stage free but putting the booster under unanticipated strain that caused it to deviate from the proper trajectory. At T+295 seconds, the deviation was detected by the Soyuz's guidance system, which activated an automatic abort program. This separated the Soyuz spacecraft from the third stage booster and then separated the orbital and service modules of the Soyuz from the re-entry capsule.
At the time when the safety system initiated separation the spacecraft was already pointed downward toward Earth, which accelerated its descent significantly. Instead of the expected acceleration in such an emergency situation of 15 g
G-force
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
(147 m/s²), the cosmonauts experienced up to 21.3 g (209 m/s²). Despite very high overloading, the capsule's parachutes opened properly and slowed the craft to a successful landing after a flight of only 21 minutes.
The capsule landed southwest of Gorno-Altaisk at a point 829 kilometres (515 mi) north of the Chinese border. The capsule landed on a snow-covered slope and began rolling downhill towards a 152 m (498.7 ft) sheer drop before it was stopped by the parachutes becoming snagged on vegetation.
Having landed in chest-deep powder snow and a local temperature of -7 °C, the cosmonauts donned their cold-weather survival clothing. Lazarev, fearing they had landed in China, burned papers relating to a military experiment he had been scheduled to perform in space. Soon, the crew was in radio contact with a rescue team in an approaching helicopter, who confirmed their landing point was in the Soviet Union, near the town of Aleysk
Aleysk
Aleysk is a town in Altai Krai, Russia, located on the Aley River , southwest of Barnaul. Population: 32,000 . It was host to Aleysk air base, and a division of the Strategic Rocket Forces....
. The deep snow, the high altitude, and the terrain meant the rescuers had great difficulty in making contact with the cosmonauts. It was the next day before they were safely air-lifted out. The crew were returned to Star City
Star City, Russia
Star City is a common name of an area in Moscow Oblast, Russia, which has since the 1960s been home to the Yuri Gagarin Cosmonaut Training Center...
; the capsule was recovered some time later.
Initial Soviet reports stated the men had suffered no ill effects from their flight. Vladimir Shatalov
Vladimir Shatalov
Vladimir Aleksandrovich Shatalov is a former Soviet cosmonaut who flew three space missions of the Soyuz programme: Soyuz 4, Soyuz 8, and Soyuz 10....
, the Director of Cosmonaut Training, reported they were fit to fly another mission. However, subsequent reports claimed that Lazarev was injured by the high acceleration of re-entry.
In Brezhnev's time it was rare to disclose anything about Soviet failures, and so the first (Soviet) publication about the realities of the flight was not made until 1983 in the Army newspaper "Red Banner". The Americans were informed on April 7 after the crew had been rescued. However, as the failure occurred during preparations for the joint Apollo-Soyuz Test Project
Apollo-Soyuz Test Project
-Backup crew:-Crew notes:Jack Swigert had originally been assigned as the command module pilot for the ASTP prime crew, but prior to the official announcement he was removed as punishment for his involvement in the Apollo 15 postage stamp scandal.-Soyuz crew:...
, the Soviets were 'requested' to provide the Americans with a more detailed report. (There was even a U. S. Congressional Inquiry regarding this failure and several others.) It was revealed that the booster used had been an older model than the one planned for use in the joint mission that July. In the report the Soviets made to the Americans, the abort was referred to as "the April 5th anomaly" and as this was the only term the Soviets ever used for the incident, it became the 'official' designation for years afterwards. The mission is referred to in the literature as Soyuz 18-1 or Soyuz 18a, since the following Soyuz mission in May 1975 received the name Soyuz 18
Soyuz 18
Soyuz 18 was a 1975 Soviet manned mission to Salyut 4, the second and final crew to man the space station. Pyotr Klimuk and Vitali Sevastyanov set a new Soviet space endurance record of 63 days and the mark for most people in space simultaneously was tied during the mission.-Crew:-Backup...
(the Soviets only gave numbers to successful launches).
The Soyuz 18a flight has been the only case of a manned booster accident at high altitude. The exact landing site of the capsule had been a subject of debate amongst space historians in subsequent years. A Russian source quoted by James Oberg
James Oberg
James Edward Oberg is an American space journalist and historian, regarded as an expert on the Russian space program.-Biography:...
has stated that the landing occurred in Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
. Other sources have claimed that the capsule came down in China, but both it and the crew were recovered before the Chinese authorities became aware of it.
Mission parameters
- Mass: 6830 kg (15,057.6 lb)
- Apogee: 192 km (119.3 mi)
See also
- Soyuz T-10-1Soyuz T-10-1-Mission parameters:*Mass: 6850 kg*Perigee: N/A*Apogee: N/A*Inclination: N/A*Period: N/A-Mission highlights:...
, 1983 Soyuz launch failure - List of space accidents