| astronautix.com | RS-27 |
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| RS-27 - Credit: Boeing / Rocketdyne. 8,503 bytes. 126 x 233 pixels. |
The RS - 27 powerplant comprises an RS2701A/B main engine, and twin LR101 - NA - 11 verniers. Introduced in 1974 on the McDonnell Douglas' Delta 2000 series launcher it replaced the MB - 3 as the main system for that launcher. It completed it's Delta service on the 6000 model in 1992. and continues in service as part of the Atlas MA- 5A powerplant. Application: Delta 6000 series. First Flown: January 18th, 1974 on Delta 100/Skynet 2A. Flown: 107 Delta plus 8 Atlas to the end of 1993. Mounting: gimballed-mounted for pitch/yaw control with gimballed verniers for roll control. Engine Cycle: gas generator. Oxidizer: liquid oxygen at 250 kg/sec. Fuel: RP-1 hydrocarbon at 111 kg/sec. Mixture Ratio: 2.245:1. Oxidizer Turbopump: 1900 kW, 6784 rpm (7085 rpm at altitude), 70 atm discharge Pressure: Fuel Turbopump: 1289 kW, 70 atm discharge Pressure. Thrust: 971 kN sea level/1023 kN vacuum. Thrust Chamber Length: 219 cm (234 cm). Thrust Chamber Materials: 347 CRES austenitic stainless steel. Thrust Chamber Cooling: regenerative, two passes of fuel through 292 tubes. Combustion Chamber Pressure: 48 atm at injector end. Combustion Chamber Temperature: 3315 Celsius. Combustion Chamber Materials: 347 CRES austenitic stainless steel. Combustion Chamber Cooling: same as thrust chamber. Combustion Chamber Ignition: hypergolic fluid cartridge enclosed in burst diaphragms. Verniers: each LR101-NA-11 at 21.8 kg mass, 4.63/5.30 kN sea level/vac thrust, 209/246 sec sea level/vac Isp, 1.8 mixture ratio, 5.6 expansion ratio(9.8 cm exit diameter), 283 sec burn time. Designed for booster applications. Gas generator, pump-fed.