Human Spaceflights

International Flight No. 58

Soyuz 23

Radon

USSR

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Launch, orbit and landing data

Launch date:  14.10.1976
Launch time:  17:40 UTC
Launch site:  Baikonur
Launch pad:  1
Altitude:  239 - 269 km
Inclination:  51.61°
Landing date:  16.10.1976
Landing time:  17:46 UTC
Landing site:  140 km SE of Arkalyk

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alternate crew photo

alternate crew photo

alternate crew photo

alternate crew photo

alternate crew photo

alternate crew photo

Crew

No.   Surname Given names Position Flight No. Duration Orbits
1  Zudov  Vyacheslav Dmitriyevich  Commander 1 2d 00h 06m  32 
2  Rozhdestvensky  Valeri Iliyich  Flight Engineer 1 2d 00h 06m  32 

Crew seating arrangement

Launch
1  Zudov
2  Rozhdestvensky
Landing
1  Zudov
2  Rozhdestvensky

Animations: Soyuz

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with friendly permission of www.marscenter.it

1st Double Crew

No.   Surname Given names Position
1  Gorbatko  Viktor Vasiliyevich  Commander
2  Glazkov  Yuri Nikolayevich  Flight Engineer

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2nd Double Crew

No.   Surname Given names Position
1  Berezovoy  Anatoli Nikolayevich  Commander
2  Lisun  Mikhail Ivanovich  Flight Engineer

Flight

Launch from the Baikonur Cosmodrome; landing 195 km southwest of Tselinograd / 140 km southeast of Arkalyk.

The Soyuz 23 ferry spacecraft suffered a docking system failure. Sensors indicated an incorrect lateral velocity, causing unnecessary firing of the thrusters during rendezvous (approach was until 100 m). The automatic system was turned off, but no fuel remained for a manual docking with the Salyut 5 space station. Crews were normally trained for a manual dock, but not for a manual approach. So the only possible solution was an immediate return to Earth.

The Soyuz spacecraft is composed of three elements attached end-to-end - the Orbital Module, the Descent Module and the Instrumentation/Propulsion Module. The crew occupied the central element, the Descent Module. The other two modules are jettisoned prior to re-entry. They burn up in the atmosphere, so only the Descent Module returned to Earth.
Having shed two-thirds of its mass, the Soyuz reached Entry Interface - a point 400,000 feet above the Earth, where friction due to the thickening atmosphere began to heat its outer surfaces. With only 23 minutes left before it lands on the grassy plains of central Asia, attention in the module turned to slowing its rate of descent.
Eight minutes later, the spacecraft was streaking through the sky at a rate of 755 feet per second. Before it touched down, its speed slowed to only 5 feet per second, and it lands at an even lower speed than that. Several onboard features ensure that the vehicle and crew land safely and in relative comfort.
Four parachutes, deployed 15 minutes before landing, dramatically slowed the vehicle's rate of descent. Two pilot parachutes were the first to be released, and a drogue chute attached to the second one followed immediately after. The drogue, measuring 24 square meters (258 square feet) in area, slowed the rate of descent from 755 feet per second to 262 feet per second.
The main parachute was the last to emerge. It is the largest chute, with a surface area of 10,764 square feet. Its harnesses shifted the vehicle's attitude to a 30-degree angle relative to the ground, dissipating heat, and then shifted it again to a straight vertical descent prior to landing.
The main chute slowed the Soyuz to a descent rate of only 24 feet per second, which is still too fast for a comfortable landing. One second before touchdown, two sets of three small engines on the bottom of the vehicle should be fired, to slowi the vehicle to soften the landing.
The spacecraft experienced a remarkable and near catastrophic return to Earth. The crew landed at night on a frozen lake (Tengiz) during a snow-storm (195 km southwest of Tselinograd / 140 km southeast of Arkalyk). The ice broke, the parachute became wet and took the escape hatch under water. The capsule was cooled and the heating systems had been turned down to conserve the battery power.
Several attempts, to reach the capsule, failed. 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. The rescue men were surprised to find the crew alive.

Photos

Soyuz 23 on the launch pad
 

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Last update on November 29, 2014.