Specifications
| J-2 | J-2S | J-2X | |
|---|---|---|---|
| Vacuum thrust: | 1,033.100 kN (232,250 lbf) | 1,138.500 kN (255,945 lbf) | 1,310.000 kN (294,490 lbf) |
| Specific impulse (vacuum) -Isp: | 421 sec. | 436 sec. | 448 sec. |
| Burn time: | 475 sec. | 475 sec. | 465 sec. (Ares I, upper stage) |
| Engine weight - dry: | 1,438 kg (3,170 lb). | 1,400 kg (3,000 lb). | 2,472 kg (5,450 lb). |
| Propellants: | LOX & LH2 | LOX & LH2 | LOX & LH2 |
| Mixture ratio: | 5.50 | 5.50 | 5.50 |
| Diameter: | 2.01 m (6.60 ft). | 2.01 m (6.60 ft). | 3.05 m (10.00 ft). |
| Length: | 3.38 m (11.08 ft). | 3.38 m (11.08 ft). | 4.70 m (15.40 ft). |
| Thrust to Weight Ratio: | 73.18. | 85.32 | 55.04 |
| Contractor: | Rocketdyne | Rocketdyne | PWR |
| Vehicle application: | Saturn V / S-II 2nd stage - 5-engines, Saturn IB & Saturn V / S-IVB upper stage - 1-engine |
Planned replacement for J-2 on Saturn V / S-II 2nd stage / S-IVB upper stage |
Proposed for Ares I upper stage - 1 engine / Ares V upper stage - 1 engine |
Read more about this topic: J-2 (rocket Engine)