S5.51 home
topic index

S5.51 LOK engine
Credit - © Mark Wade

Engine Model: S5.51. Government Designation: 11D68. Other Designations: S5.51. Designer: Isayev. Developed in: 1964-72. Application: Soyuz LOK lunar orbiter. Propellants: N2O4/UDMH. Thrust(vac): 33.196 kN (7,463 lbf). Throttled thrust(vac): 4.089 kN (919 lbf). Isp: 314 sec. Burn time: 700 sec. Mass Engine: 480 kg (1,050 lb). Length: 2.77 m (9.08 ft). Chambers: 2 + 1. Oxidizer to Fuel Ratio: 1.85. Thrust to Weight Ratio: 7.05. Country: Russia. Status: Hardware. First Flight: 1969.

Complex engine used to maneuver the LOK to a rendezvous with the LK lander in lunar orbit, then propel the LOK out of lunar orbit (large engine), and for midcourse corrections (small engine). Burn time 700 + 300 sec. Oxidizer to fuel ratio 1,85 / 1,76.



S5.51 used on Spacecraft


Bibliography:

  • Semenov, Yu. P., S P Korolev Space Corporation Energia, RKK Energia, 1994.
  • Haeseler, Dietrich, Visit to the museum of Chemical Machining Design Bureau, Kalinin 1994 via Dietrich Haeseler.


Contact us with any corrections, additions, or comments.
Conditions for use of drawings, pictures, or other materials from this site..
To contact astronauts or cosmonauts.

© Mark Wade, 1997 - 2008 except where otherwise noted.