RD-843
| Country of origin | Ukraine |
|---|---|
| First flight | 2012-02-13 |
| Designer | Yuzhnoye Design Bureau |
| Manufacturer | Yuzhmash |
| Application | Upper stage |
| Associated LV | Vega, Vega C |
| Predecessor | RD-869 |
| Status | In production |
| Liquid-fuel engine | |
| Propellant | N2O4 / UDMH |
| Mixture ratio | 2.0 |
| Cycle | Pressure-fed |
| Configuration | |
| Chamber | 1 |
| Performance | |
| Thrust, vacuum | 2.452 kN (551 lbf) |
| Chamber pressure | 2.04 MPa (296 psi) |
| Specific impulse, vacuum |
|
| Burn time |
|
| Restarts | Up to 5 |
| Gimbal range | ±10° |
| Dimensions | |
| Dry mass | 15.93 kg (35.1 lb) |
| Used in | |
| AVUM, AVUM+ | |
| References | |
| References | |
The RD-843 is a Ukrainian single nozzle liquid propellant rocket engine. It burns a hypergolic mixture of unsymmetrical dimethylhydrazine (UDMH) fuel with dinitrogen tetroxide (N2O4) oxidizer. It is pressure-fed. It is rated for up to 5 restarts, and can gimbal up to 10 degrees in each direction.
It was developed by Yuzhnoye Design Bureau for Avio and is manufactured by Yuzhmash. It uses the RD-869 thrust chamber, the old Soviet ICBM SS-18 final stage engine from which it is evolved, and which was also designed by Yuzhnoye. The RD-843 ground test campaign included 74 tests, 140 ignitions, reaching a total of 8,201 seconds, which is approximately 12 service lives on 4 engines. As of June 2020 it has been successfully used on 14 orbital launches.
The Vega and Vega C uses it as the main engine on its AVUM (Attitude & Vernier Upper Module) fourth stage which it calls the MEA (short for Main Engine AVUM).