Engine Model: RD-216. Manufacturer Name: RD-216. Government Designation: 11D614. Designer: Glushko. Developed in: 1958-60. Application: R-14, Kosmos 11K63 stage 1. Propellants: Nitric acid/UDMH. Thrust(vac): 1,728.000 kN (388,469 lbf). Thrust(sl): 1,469.200 kN (330,289 lbf). Isp: 291 sec. Isp (sea level): 248 sec. Burn time: 146 sec. Mass Engine: 1,350 kg (2,970 lb). Diameter: 2.26 m (7.41 ft). Length: 2.20 m (7.20 ft). Chambers: 4. Chamber Pressure: 73.60 bar. Area Ratio: 18.80. Oxidizer to Fuel Ratio: 2.50. Thrust to Weight Ratio: 131.40. Country: Russia. First Flight: 1964. Last Flight: 2005. Flown: 788. RD-216 is a block of 2 RD-215's. The RD-216 had 2 combustion chambers and 2 turbines. Two sets of these were used in the first stage of the R-14 missile and Kosmos 11K63 series launch vehicles. Beginning with this engine Glushko cut the previous 3 to 5 year development time for new engines to 2 years. Diameter is per chamber.