Gross Mass: 1,361,000 kg.
Empty Mass: 122,000 kg. Thrust (vac): 1,361,000 kgf. Isp: 428 sec. Burn time: 383 sec. Propellants: Lox/LH2Diameter: 20.0 m. Span: 20.0 m. Length: 45.4 m. Country: USA. No Engines: 2. M-1Status: Study 1963. Comments: Operational date would have been February 1973 .