HM7B
| Country of origin | France | 
|---|---|
| First flight | 24 December 1979 | 
| Designer | Snecma | 
| Manufacturer | Snecma | 
| Application | Upper stage engine | 
| Predecessor | HM4 | 
| Successor | Vinci | 
| Status | Retired | 
| Liquid-fuel engine | |
| Propellant | LOX / LH2 | 
| Mixture ratio | 5:1 | 
| Cycle | Gas-generator | 
| Configuration | |
| Chamber | 1 | 
| Nozzle ratio | 83.1:1 | 
| Performance | |
| Thrust, vacuum | 62.2 kN (13,980 lbf) | 
| Chamber pressure | 3.7 MPa (37 bar) | 
| Specific impulse, vacuum | 444.6 s (4.36 km/s) | 
| Dimensions | |
| Length | 2.01 m (6 ft 7 in) | 
| Diameter | 0.992 m (3 ft 3.1 in) | 
| Dry mass | 165 kg (364 lb) | 
| Used in | |
| References | |
| References | |
The HM7B was a European cryogenic upper stage rocket engine used on the vehicles in the Ariane rocket family. It was replaced by Vinci, which acts as the new upper stage engine on Ariane 6. Nearly 300 engines have been produced to date.