 The RD-855 engine is intended to control flight of the
Cyclone LV first stage in all channels. The stage flight control is provided by gimbaling each chamber in one tangential plate.
Design simplicity and high reliability.
The autonomous four-chamber pump-fed steering engine of a single run operates on hypergolic propellants under the generator scheme
(without afterburning of the generator gas)
The TPU turbine's working medium is a gas produced by the gas generator at combustion of the main propellants. The TPU rotor is
spinned up during the startup by pyrostarter.
Major part of valves is activated by pyrotechnical elements. The non-return valves in the oxidizer channel of the chamber and a set of
valves in the oxidizer channel of the gas generator allow oxidizer delivery at achievement of specified opening pressure of these valves.
The engine provides tapping of both propellants to the gas generator of oxidizer tank pressurization, as well as tapping of the generator
gas for the mixer to pressurize the fuel tank.
| Sea level thrust, kgf | 29100 |
Specific impulse, s:
- at sea level
- in vacuum |
254
292 |
| Mass, kg | 320 |
| Combustion chamber absolute pressure, kgf/cm2 | 67 |
| Nozzle exit absolute pressure, kgf/cm2 | 0.6 |
| Mixture ratio | 1.97 |
| Thrust deviation from the nominal value, % | ±10 |
| Mixture ratio deviation from the nominal value, % | ±5.6 |
Propellants:
- oxidizer
- fuel |
NTO
UDMH |
Min inlet propellant absolute pressure, kgf/cm2, at +35°Ñ temperature:
- oxidizer
- fuel |
4.5
1.45 |
| Chambers gimbal angle, deg | ±41 |
| Firing time, s | 127 |
|
Development of company
