Sapwood SS-6 8K71PS
Stages		1 1/2
0 - Strap-on Boosters	Engines	4 x RD-107
Thrust		4 x 99,000 kgf = 396 Mgf (3.89 MN)
Burn time		118 seconds
Fuels		Lox/Kerosene
1 - Core Stage	Engines	1 x RD-108
Thrust		912 kN
Burn time		301 seconds
Fuels		Lox/Kerosene
Launch Vehicle		1st Launch October 4, 1957
Payload LEO 65-degree		500 kg

Sapwood SS-6 8K71PS was an ICBM used as a launch vehicle by the Soviet Union to launch Sputnik 1 and Sputnik 2. No other rocket stages were added to the ICBM to launch the satellites. The SS-6 8K71PS is essentially a modified R-7 ICBM. It was also known under the name "semiorka".

Sapwood SS-6 8K71PS specifications

• Stage Number: 0 - Strap-on Boosters; 4 x 8K71K-0
  • Gross Mass: 43,300 kg
  • Empty Mass: 3,710 kg
  • Thrust (vac): 4 × 99,000 kgf = 396 Mgf (3.89 MN)
  • Isp: 313 kgf·s/kg (3.07 kN·s/kg)
  • Burn time: 118 s
  • Isp(sl): 256 kgf·s/kg (2.51 kN·s/kg)
  • Diameter: 2.68 m
  • Span: 9.76 m
  • Length: 19.00 m
  • Propellants: Lox/Kerosene
  • Engines: 1 x RD-107-8D74-1959 per booster = 4

• Stage Number: 1 - Core stage; 1 x 8K71K-1
  • Gross Mass: 100,400 kg
  • Empty Mass: 6,800 kg
  • Thrust (vac): 912 kN
  • Isp: 315 kgf·s/kg (3.09 kN·s/kg)
  • Burn time: 301 s
  • Isp(sl): 248 kgf·s/kg (2.43 kN·s/kg)
  • Diameter: 2.99 m
  • Length: 28.00 m
  • Propellants: Lox/Kerosene
  • Engine: 1 x RD-108-8D75-1959

• Total Mass: 267,000 kg
• Total Liftoff Thrust: 3.89 MN