S-II
 | |
| Manufacturer | North American |
|---|---|
| Country of origin | United States |
| Used on | Saturn V |
| General characteristics | |
| Height | 81 ft 8 in (24.9 m) |
| Diameter | 32 ft 10 in (10 m) |
| Gross mass | 1,058,000 lb (480,000 kg) |
| Propellant mass | 977,000 lb (443,000 kg) |
| Empty mass | 79,700 lb (36,200 kg) |
| Launch history | |
| Status | Retired |
| Total launches | 13 |
| Successes (stage only) | 12 |
| Other | Partial failure (Apollo 6) |
| First flight | November 9, 1967 (Apollo 4) |
| Last flight | May 14, 1973 (Skylab 1) |
| Specifications | |
| Powered by | 5 × J-2 |
| Maximum thrust | 1,000,000 lbf (4,400 kN) |
| Specific impulse | 421 s (4.13 km/s) |
| Burn time | 367 seconds |
| Propellant | LH2 / LOX |
The S-II (pronounced "S-two") was the second stage of the Saturn V rocket. It was built by North American Aviation. Using liquid hydrogen (LH2) and liquid oxygen (LOX) it had five J-2 engines in a quincunx pattern. The second stage accelerated the payload through the upper atmosphere with 1,000,000 pounds-force (4.4 MN) of thrust.