Prometheus Reusable Rocket Engine
arianegroup
ArianeGroup's Prometheus — Europe's first LOX/methane reusable rocket engine designed to reduce costs by a factor of 10 vs. Vulcain, targeting future reusable European launchers.
Key figurescomparable across the catalogue
- Thrust
- 100,000 N
Normalised to common units so this product can be compared with others in its category. The supplier's own wording is below.
As published by the supplier
- Propellants
- LOX/Liquid Methane (LCH4)
- Thrust
- ~100 kN
- Cycle
- Gas generator
- Manufacturing
- Extensive 3D metal printing of components
- Reuse Target
- 10+ flights
- Platform
- Themis reusable stage demonstrator / future Ariane NEXT
- Program
- ESA Future Launchers Preparatory Programme (FLPP)
About
Prometheus is ArianeGroup’s technology demonstrator engine for Europe’s next-generation reusable launch capability. The engine burns LOX/liquid methane (LCH4) and is designed to cost 10 times less than the current Vulcain 2.1 engine that powers Ariane 6’s core stage. The cost reduction is achieved through 3D metal printing of key components (including the thrust chamber), simplified gas generator cycle, and design for reusability (with the target of 10+ flight reuse).
Prometheus produces approximately 100 kN of thrust and is being developed under ESA’s Future Launchers Preparatory Programme (FLPP). It serves as the core propulsion unit for Themis, ArianeGroup’s technology demonstrator for a reusable first stage (analogous to SpaceX Falcon 9’s reusable booster concept). Themis flew a suborbital hop demonstrator in 2023–2024 at Kourou to demonstrate vertical landing.
The long-term goal is Ariane NEXT (or a derivative), a reusable European launch vehicle that would use Prometheus-derived engines to compete with Falcon 9’s cost profile. ArianeGroup is a 50/50 joint venture between Airbus and Safran, headquartered in Les Mureaux, France.
Documentation
No public datasheet yet — request the datasheet / ICD from the supplier.