Space Shuttle Main Engine (Boeing Rocketdyne)
| Specification | 1989 (109% thrust) | 1998 (Phase II, 109% thrust) |
|---|---|---|
| Applications | Space Shuttle and future RLVs | |
| Propellants | LOX/LH2 | |
| Thrust in Vacuum | 512,300 lb | 512,410 lb |
| Thrust at Sea Level | 408,750 | 418,130 |
| Isp in vacuum(s) | 453.5 | 454.4 |
| Isp at sea level | ||
| Mixture Ratio | 6.0:1 | 6.0:1 |
| Weight | 6,990 lb | 6990 |
| Chamber Pressure | 3260 psia | 3280 |
| Area Ratio | 77.5:1 | 77.5:1 |
| Engine Cycle | ???? | |
| Hydrogen Pump Discharge | 7040 psia | 6860 |
| Oxygen Pump Discharge | 8070 psia | 8040 |
RS-68 : XRS-2200 