N1F Sr

Russian heavy-lift orbital launch vehicle. The final more modest version of the N1F replaced the fourth and fifth stages of the N1 with the single liquid oxygen/liquid hydrogen Block Sr stage. Development of the Sr stage was from May 1971 until cancellation of the N1 project in May 1974.

Stage Data - N1F Sr

• Stage 1. 1 x N1F Block A. Gross Mass: 2,070,000 kg (4,560,000 lb). Empty Mass: 126,230 kg (278,280 lb). Thrust (vac): 49,675.500 kN (11,167,497 lbf). Isp: 331 sec. Burn time: 125 sec. Isp(sl): 297 sec. Diameter: 10.00 m (32.00 ft). Span: 15.60 m (51.10 ft). Length: 30.00 m (98.00 ft). Propellants: Lox/Kerosene. No Engines: 30. Engine: NK-33. Status: In Production. Comments: Includes 14,000 kg for Stage 1-2 interstage.

• Stage 2. 1 x N1F Block B. Gross Mass: 620,000 kg (1,360,000 lb). Empty Mass: 55,700 kg (122,700 lb). Thrust (vac): 14,040.004 kN (3,156,318 lbf). Isp: 346 sec. Burn time: 120 sec. Diameter: 6.80 m (22.30 ft). Span: 9.80 m (32.10 ft). Length: 20.00 m (65.00 ft). Propellants: Lox/Kerosene. No Engines: 8. Engine: NK-43. Status: In Production. Comments: Includes 3,500 kg for Stage 2-3 interstage.

• Stage 3. 1 x N1F Block V. Gross Mass: 210,000 kg (460,000 lb). Empty Mass: 13,700 kg (30,200 lb). Thrust (vac): 1,608.000 kN (361,492 lbf). Isp: 353 sec. Burn time: 370 sec. Diameter: 4.80 m (15.70 ft). Span: 6.80 m (22.30 ft). Length: 12.00 m (39.00 ft). Propellants: Lox/Kerosene. No Engines: 4. Engine: NK-39. Status: In Production.

• Stage 4. 1 x N1 Block Sr. Gross Mass: 77,900 kg (171,700 lb). Empty Mass: 11,500 kg (25,300 lb). Thrust (vac): 147.880 kN (33,245 lbf). Isp: 441 sec. Burn time: 1,910 sec. Diameter: 5.20 m (17.00 ft). Span: 5.20 m (17.00 ft). Length: 16.50 m (54.10 ft). Propellants: Lox/LH2. No Engines: 2. Engine: RD-56M. Status: Development 1974. Comments: Upper stage developed 1971-1974 to support manned lunar expedition. Replaced Blok R/Blok S previously under development. Capable of five restarts and 11 days of flight. Could insert 24 metric tons into lunar orbit or 20 metric tons into geosynchronous orbit.