RD-855
Engine · Ukraine
Original archive entry. The text, images and links below are kept as they were written.
Credit: Yuzhnoye
Yuzhnoye N2O4/UDMH rocket engine. Tsyklon stage 1 attitude control engine. Out of Production. Four-chamber pump-fed single-run engine burned hypergolic propellants in a gas generator scheme.
The autonomous four-chamber pump-fed single-run engine burned hypergolic propellants in a gas generator scheme (without afterburning of the generator gas). Most valves were activated by pyrotechnics. The engine flow scheme tapped off both propellants to the feed the oxidizer tank pressurization gas generator, as well generator gas for the fuel tank pressurization mixer. Thrust controlled to within ±10% of nominal value, propellant mixture ratio within ± 5.6%. Engine thrust controlled by gimballing each of the four chambers in one plane, ± 41 deg.
Chambers: 4. Thrust (sl): 285.400 kN (64,160 lbf). Thrust (sl): 29,103 kgf. Engine: 320 kg (700 lb). Chamber Pressure: 65.70 bar. Thrust to Weight Ratio: 90.94. Oxidizer to Fuel Ratio: 1.97.