Status
Success
Cosmos 997 & 998
Thu Mar 30, 1978 00:00 UTC
Rocket
Mission Details
Cosmos 997 & 998
The TKS-VA (Transportniy Korabl Snabzheniya - Vozvrashemui Apparat) reentry capsule was the reentry module of the TKS (FGB) spacecraft. The VA was capable of 31 hours of autonomous flight after separation from the TKS. A crew of three could be carried. Access to the TKS on the pad was through a square hatch in the side of the capsule, which could also be used to conduct EVA's in orbit, with the VA acting as an air lock for the TKS. The TKS could be accessed via a hatch in the heat shield below the middle seat. With the crew, 50 kg of payload could be returned. Uncrewed 500 kg of payload could be returned.
The BSO (Bloka Skhoda s Orbiti) housed the retro-rocket for deorbit of the VA capsule following separation from the space station. It was unusually mounted at the nose of the spacecraft. It also provided the additional battery power, orientation rockets, and radio equipment that gave the VA a 31 hour autonomous flight duration after separation from the TKS orbital module.
The VA capsule had a hypersonic lift to drag ratio of 0.25, which allowed the BSU-V crewed capsule guidance system to manoeuvre the spacecraft to its landing point using the optimum path for minimal heating and deceleration. Once the capsule was subsonic a drogue parachute deployed for seven seconds, followed by the 1770 square meters main chute. The capsule made a soft landing using a retrorocket in the parachute lines, triggered by the Probki radioactive sensor system within the Kaktus gamma ray altimeter.
For initial tests, the VA was launched without the TKS in pairs for one or two orbit missions. In these double launches, only the upper spacecraft had a rescue rocket system.