Soyuz 25
Encyclopedia
Soyuz 25 was a 1977 Soviet manned space flight, the first to the new Salyut 6
Salyut 6
Salyut 6 , DOS-5, was a Soviet orbital space station, the eighth flown as part of the Salyut programme. Launched on 29 September 1977 by a Proton rocket, the station was the first of the 'second-generation' type of space station. Salyut 6 possessed several revolutionary advances over the earlier...

 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...

, which had been launched 10 days earlier. However, the mission was aborted when cosmonauts Vladimir Kovalyonok
Vladimir Kovalyonok
-Honours and awards:* Hero of the Soviet Union, twice * Order of Merit for the Fatherland, 3rd class * Order of Military Merit * Three Orders of Lenin...

 and Valery Ryumin
Valery Ryumin
Valery Victorovich Ryumin, born August 16, 1939 in Komsomolsk-on-Amur) is a former Soviet cosmonaut.In 1958, he was graduated from the Kaliningrad Mechanical Engineering Technical College with the specialty "Cold Working of Metal." In 1966, he was graduated from the Department of Electronics and...

 failed to engage the docking latches of the station despite five attempts. Lacking sufficient fuel to attempt a dock at the other end of the station and with battery power for only two days, they returned to Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

.

The failure led to a new rule whereby every crew had to have at least one person aboard who had previously flown in space.

Crew

Backup crew

Mission Highlights

Soyuz 25 was launched on 9 October 1977 with a crew of two cosmonauts to dock with the orbiting Salyut 6 space station, which had been launched 10 days earlier, on 29 September. The crew were to stay on board for about 90 days, which would break the Soviet space endurance record, and possibly the all-time record of 84 days held by the crew of Skylab 4
Skylab 4
Skylab 4 was the fourth Skylab mission and placed the third and final crew on board the space station. The mission started November 16, 1973 with the launch of three astronauts on a Saturn IB rocket, and lasted 84 days, 1 hour and 16 minutes...

. The station was a new version of a Salyut
Salyut
The Salyut program was the first space station program undertaken by the Soviet Union, which consisted of a series of nine space stations launched over a period of eleven years from 1971 to 1982...

 with modifications including a second docking port which allowed supply ships and other crews to visit during the duration of a mission.

The vehicle approached the station the next day, and it contacted the forward port, but the Soyuz craft failed to make a hard dock with the station. The cosmonauts told the ground crew that they had attempted to dock four times, but that the contact light failed to come on. While the crew waited in soft dock - the docking system probe was latched onto the Salyut docking drouge, but the probe had failed to retract and bring the craft together - the ground crew studied the problem.

On the 20th orbit, Kovalenko undocked the Soyuz, and attempted to dock for the fifth time during the 23rd orbit, but failed again. The decision was made to return to earth, as the Soyuz was equipped with batteries designed to last about two days, and the craft lacked fuel to attempt to dock with the port on the opposite side of the station.

A news release was issued: "At 07.09 Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...

 time today (10 October) the automatic rendezvous of the Soyuz 25 ship and the Salyut 6 station was begun. From a distance of 120 metres, the vehicles performed a docking manoeuvre. Due to deviations from the planned procedure for docking, the link-up was called off. The crew has begun making preparations for a return to Earth."

The crew thus had to make an early reentry
Atmospheric reentry
Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...

 and landed 185 km (115 mi) northwest of Tselinograd, Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...

 on 11 October.

The failure was a serious blow to the Soviets, as their media had given the flight a high profile, noting that the flight had come from the same launchpad as Sputnik 1
Sputnik 1
Sputnik 1 ) was the first artificial satellite to be put into Earth's orbit. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957. The unanticipated announcement of Sputnik 1s success precipitated the Sputnik crisis in the United States and ignited the Space...

 and Vostok 1
Vostok 1
Vostok 1 was the first spaceflight in the Vostok program and the first human spaceflight in history. The Vostok 3KA spacecraft was launched on April 12, 1961. The flight took Yuri Gagarin, a cosmonaut from the Soviet Union, into space. The flight marked the first time that a human entered outer...

, and coincided with the 60th anniversary of the October Revolution
October Revolution
The October Revolution , also known as the Great October Socialist Revolution , Red October, the October Uprising or the Bolshevik Revolution, was a political revolution and a part of the Russian Revolution of 1917...

.

The problem was traced later to a faulty mechanism on the Soyuz; this was not discovered until after the Soyuz 26
Soyuz 26
Soyuz 26 was Soviet manned mission, used to launch the crew of Salyut 6 EO-1, the first long duration crew on the space station Salyut 6.The Soyuz spacecraft was launched on December 10, 1977, and docked with the space station the next day...

 flight performed an EVA
Extra-vehicular activity
Extra-vehicular activity is work done by an astronaut away from the Earth, and outside of a spacecraft. The term most commonly applies to an EVA made outside a craft orbiting Earth , but also applies to an EVA made on the surface of the Moon...

 to inspect the second docking port on Salyut 6.

The mission failure resulted in a rule stating that future crews would include at least one cosmonaut who had already flown a space mission. This resulted in the all-rookie backup crew of Aleksandr Ivanchenkov
Aleksandr Ivanchenkov
Aleksandr Sergeyevich Ivanchenkov is a retired Soviet cosmonaut who flew as Flight Engineer on Soyuz 29 and Soyuz T-6, he spent 147 days, 12 hours and 37 minutes in space....

 and Yuri Romanenko
Yuri Romanenko
Yury Viktorovich Romanenko is a former Soviet cosmonaut, twice Hero of the Soviet Union . Over his career, Yury Romanenko spent a total of 430 days 20 hours 21 minutes 30 seconds in space and 18 hours in space walks. In 1987 he was a resident of the Mir space station, launching on Soyuz TM-2 and...

 being paired with veteran cosmonauts for future missions. The rule was not relaxed until 1994 and Soyuz TM-19
Soyuz TM-19
-Crew:-Mission highlights:Commander Malenchenko and Flight Engineer Musabayev, spaceflightrookies, were to have been launched with veteran cosmonaut GennadiStrekalov, who would have returned to Earth with Viktor Afanaseyev and Yuri...

.

Mission parameters

  • Mass: 6860 kg (15,123.7 lb)
  • Perigee: 198.5 km (123.3 mi)
  • Apogee: 258.1 km (160.4 mi)
  • Inclination: 51.66°
  • Period: 88.66 minutes
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