AKA: Proton-2. Status: Retired 1966. Thrust: 2,399.19 kN (539,359 lbf). Gross mass: 134,900 kg (297,400 lb). Unfuelled mass: 13,180 kg (29,050 lb). Specific impulse: 325 s. Burn time: 160 s. Height: 10.90 m (35.70 ft). Diameter: 4.15 m (13.61 ft). Span: 4.15 m (13.61 ft).
No Engines: 4.