YaKhR-2

Russian nuclear-powered orbital launch vehicle. First large space launcher considered in the Soviet Union. It would have had the same layout as the R-7, but with six strap-ons increased in size by 50%. The core, igniting at altitude, used a nuclear thermal engine using ammonia as propellant. Dropped in favor of development of conventional chemical propulsion.

LEO Payload: 40,000 kg (88,000 lb) to a 185 km orbit.

Stage Data - YaKhR-2

• Stage 0. 6 x YaKhR-2 Strap-on. Gross Mass: 110,000 kg (240,000 lb). Empty Mass: 8,250 kg (18,180 lb). Thrust (vac): 2,393.724 kN (538,131 lbf). Isp: 311 sec. Burn time: 125 sec. Isp(sl): 269 sec. Diameter: 3.33 m (10.92 ft). Span: 3.33 m (10.92 ft). Length: 27.00 m (88.00 ft). Propellants: Lox/Kerosene. No Engines: 6. Engine: RD-111. Status: Study 1959. Comments: R-7 strap-ons increased in size dimensionally 50%, equipped with 6 engines from R-9. Boost nuclear thermal core stage to altitude before ignition of nuclear engine. Masses calculated based on vehicle total weight and performance.

• Stage 1. 1 x YaKhR-2 Core. Gross Mass: 180,000 kg (390,000 lb). Empty Mass: 22,000 kg (48,000 lb). Thrust (vac): 1,660.000 kN (373,180 lbf). Isp: 470 sec. Burn time: 430 sec. Isp(sl): 430 sec. Diameter: 3.33 m (10.92 ft). Span: 3.33 m (10.92 ft). Length: 37.00 m (121.00 ft). Propellants: Nuclear/Ammonia. No Engines: 1. Engine: YaRD OKB-456. Status: Study 1959. Comments: Engines in development by Bondaryuk and Glushko. Alternate propellants ammonia only or ammonia/alcohol mixture. Four expansion nozzles fed by single reactor. Masses calculated based on given vehicle gross weight and performance.