Encyclopedia Astronautica
Soyuz 7K-L1 PAO


Russian manned spacecraft module. 12 launches, 1967.03.10 (Cosmos 146) to 1970.10.20 (Zond 8). Modification of Soyuz 7K-OK basic PAO service module with pump-fed main engines and separate RCS/main engine propellant feed system. Equipment-engine section.

KTDU-53 engine with no back-up thrusters, translunar celestial navigation system, and smaller area solar panels in contrast to standard Soyuz configuration.

RCS Coarse No x Thrust: 14 X 98 N. RCS Fine No x Thrust: 4 X 98 N. RCS Coarse Backup No x Thrust: 8 x 10 N. RCS Fine Backup No x Thrust: 4 x 10 N roll. Electric System: 0.50 average kW.

AKA: Priborno-agregatniy otsek.
Gross mass: 2,700 kg (5,900 lb).
Unfuelled mass: 2,300 kg (5,000 lb).
Height: 2.26 m (7.41 ft).
Diameter: 2.15 m (7.05 ft).
Thrust: 4.17 kN (937 lbf).
Specific impulse: 276 s.

More... - Chronology...


Associated Countries
Associated Spacecraft
  • Soyuz 7K-L1 Russian manned lunar flyby spacecraft. 12 launches, 1967.03.10 (Cosmos 146) to 1970.10.20 (Zond 8). The Soyuz 7K-L1, a modification of the Soyuz 7K-OK, was designed for manned circumlunar missions. More...

Associated Engines
  • KTDU-53 Isayev Nitric acid/UDMH rocket engine. 4.089 kN. Zond 4-7 maneuvering engine. Out of Production. Spacecraft maneuvering engine, derivative of KTDU-35 without back-up engine. Isp=280s. More...

See also
Associated Propellants
  • Nitric acid/UDMH Drawing on the German World War II Wasserfall rocket, nitric acid (HNO3) became the early storable oxidiser of choice for missiles and upper stages of the 1950's. To overcome various problems with its use, it was necessary to combine the nitric acid with N2O4 and passivation compounds. These formulae were considered extremely secret at the time. By the late 1950's it was apparent that N2O4 by itself was a better oxidiser. Therefore nitric acid was almost entirely replaced by pure N2O4 in storable liquid fuel rocket engines developed after 1960. Unsymmetrical Dimethylhydrazine ((CH3)2NNH2) became the storable liquid fuel of choice by the mid-1950's. Development of UDMH in the Soviet Union began in 1949. It is used in virtually all storable liquid rocket engines except for some orbital manoeuvring engines in the United States, where MMH has been preferred due to a slightly higher density and performance. More...

Home - Browse - Contact
© / Conditions for Use