# ArianeGroup and ESA test reusable methane engine Prometheus on upgraded P5 bench

- Published: 2026-11-10 09:37 UTC
- Section: Power & Energy › Engines
- Tags: Prometheus rocket engine, reusable methane engine, ESA P5 test bench, ArianeGroup hot-fire test, cold gas spray additive manufacturing
- URL: https://realtech.media/news/rt-95b3c8926a089b74b4933538_arianegroup_and_esa/

**Europe's Prometheus prototype demonstrated multiple restarts without a starter system and verified a cold-gas-sprayed combustion chamber.**

![ArianeGroup and ESA test reusable methane engine Prometheus on upgraded P5 bench](https://realtech.media/media/2026/11/82c9bc943076275e.webp)
*Interesting Engineering*

On 29 October 2026, the Prometheus reusable rocket engine completed a series of hot-fire tests at the P5 test bench in Lampoldshausen, Germany, according to esa.int [1]. Supported by the European Space Agency (ESA) through its Future Launchers Preparatory Programme and developed by prime contractor ArianeGroup, the demonstrator uses liquid oxygen and liquid methane propellants. The system has power comparable to the Vulcain 2.1 engine used on Ariane 6 and is designed for in-flight restarting across multiple missions.

During the trials, Prometheus confirmed it could reignite repeatedly relying solely on engine inlet pressures, eliminating the need for a dedicated high-pressure starter system [1]. ArianeGroup reported that this represents a first in Europe for an engine of this class. The campaign also served to evaluate a new combustion chamber manufactured using cold gas spray, an additive production method where metal powder is accelerated to high speeds to bond to the chamber body without melting, reducing production times and overall manufacturing costs.

## Facility upgrades at Lampoldshausen

The P5 test stand, owned by ESA and operated by the German Aerospace Center (DLR), was upgraded specifically to handle liquid methane infrastructure alongside its traditional liquid hydrogen capabilities [1]. It is one of the largest cryogenic test sites in Europe, having previously qualified the Vulcain family for Ariane rockets and the Ariane 6 upper stage. The modernized setup enables quick switching between hydrogen and methane supply circuits while providing automated controls to support multiple hot-fire procedures in a single day.

## Next development phase

The validation of key technologies on the modernized stand clears the way for testing future European launcher stages [1]. ArianeGroup plans to continue testing with an improved version designated Prometheus Mark 2. The upcoming test campaign for the updated engine is scheduled to take place at ArianeGroup's test facility in Vernon, France.

## Sources

1. [esa.int](https://www.esa.int/articles/about-us/directorates/space-transportation/future-space-transportation/prometheus-reusable-rocket-engine-fires-up-at-improved-test-bench)
2. [Interesting Engineering](https://interestingengineering.com/space/reusable-rocket-engine-passes-crucial-spaceflight-test)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-95b3c8926a089b74b4933538_arianegroup_and_esa/