S5.92

S5.92

Country of origin	USSR
First flight	1988-07-07
Designer	KB KhIMMASH
Application	Upper Stage
Associated L/V	Soyuz, Zenit
Status	In Production
Liquid-fuel engine
Propellant	N2O4 / UDMH
Mixture ratio	2.0
Cycle	Gas Generator
Configuration
Chamber	1
Performance
Thrust (vac.)	19.61 kilonewtons (4,410 lbf)
Chamber pressure	9.61 megapascals (1,394 psi)
Isp (vac.)	327 seconds
Burn time	2,000 seconds
Dimensions
Length	1,028 millimetres (40.5 in)
Diameter	838 millimetres (33.0 in)(max)
Dry weight	75 kilograms (165 lb)
Used in
Fregat and Phobos program
References
References

The S5.92 is a Russian rocket engine, currently used on the Fregat upper stage.

Design

S5.92 burns a hypergolic mixture of UDMH and nitrogen tetroxide in the gas-generator cycle. It has two throttle settings. The highest produces 19.61 kilonewtons (4,410 lbf) of thrust, a specific impulse of 327 seconds, and a 3 second ignition transient. The lower throttle level produces 13.73 kilonewtons (3,090 lbf) of thrust, specific impulse of 316 seconds, and a 2.5 second ignition transient. It is rated for 50 ignitions, and 300 days between ignitions.

History

It was originally designed by the famous A.M. Isayev Chemical Engineering Design Bureau, for the two spacecraft of the Phobos program. While the Mars missions were unsuccessful, the spacecraft manufacturer, NPO Lavochkin, found a market niche for the technology. Thus, the engine was adapted for use on the optional Fregat upper stage of the Soyuz and Zenit launch vehicles.

See also

• Fregat - The upper stage that is powered by the S5.92.
• Soyuz - A medium lift rocket that uses the Fregat stage.
• Zenit-3F - A heavy lift rocket that uses the Fregat stage.

External links

• KB KhIMMASH Official Page (in Russian)
• NPO Lavochkin Fregat Page (in Russian)