RD-180
RD-180 test firing at Marshall Space Flight Center | |
| Country of origin | Russia |
|---|---|
| First flight | 24 May 2000 |
| Designer | NPO Energomash |
| Manufacturer | NPO Energomash |
| Application | Booster |
| Predecessor | RD-170 |
| Status | Active |
| Liquid-fuel engine | |
| Propellant | LOX / RP-1 |
| Mixture ratio | 2.72 (73% O 2, 27% RP-1) |
| Cycle | Staged combustion |
| Configuration | |
| Chamber | 2 |
| Nozzle ratio | 36.87 |
| Performance | |
| Thrust, vacuum | 4,150 kN (930,000 lbf) |
| Thrust, sea-level | 3,830 kN (860,000 lbf) |
| Throttle range | 47–100% |
| Thrust-to-weight ratio | 78.44 |
| Chamber pressure | 26.7 MPa (3,870 psi) |
| Specific impulse, vacuum | 338 s (3.31 km/s) |
| Specific impulse, sea-level | 311 s (3.05 km/s) |
| Mass flow | 1,250 kg/s (165,000 lb/min) |
| Burn time | 270 seconds |
| Dimensions | |
| Length | 3.56 m (11.7 ft) |
| Diameter | 3.15 m (10.3 ft) |
| Dry mass | 5,480 kg (12,080 lb) |
The RD-180 (Russian: Ракетный Двигатель-180 (РД-180), romanized: Raketnyy Dvigatel-180, lit. 'Rocket Engine-180') is a rocket engine that was designed and built in Russia. It features a dual combustion chamber, dual-nozzle design and is fueled by a RP-1/LOX mixture. The RD-180 is derived from the RD-170 line of rocket engines, which were used in the Soviet Energia launch vehicle. The engine was developed for use on the US Atlas III and Atlas V launch vehicles and first flew in 2000. It was never used on any other rocket. The engine has flown successfully on all six Atlas III flights and on 99 Atlas V flights, with just a single non-critical failure in March 2016.
Atlas V is being phased out due to the national security implications of reliance on the Russian-built engine, which became a concern after the Russian annexation of Crimea. In 2021, Atlas manufacturer United Launch Alliance announced that it was retiring the Atlas V and that it had already taken delivery of the RD-180 engines for the remaining rockets. As of June 2024, 16 launches remain. In 2022, Russian supplies and maintenance were discontinued as the result of trade sanctions imposed after the 2022 Russian invasion of Ukraine.