ESA sign €135 million contract for low-cost 3D printed rocket engine

The Prometheus rocket engine is designed to be capable of producing 1000 kN of thrust aboard core, booster or upper stages.
The Prometheus project was initiated by French agency CNES in 2015 to produce an ultra-low cost 3D printed rocket engine for future European launch vehicles | Image credit: ArianeGroup

The European Space Agency has signed a contract with French aerospace firm ArianeGroup to continue the development of a low-cost 3D-printed rocket engine.

The €135 million contract was signed on May 17 during a virtual ceremony. The contract provides funding to complete static-fire testing of two existing full-scale demonstrators of the Prometheus engine. It also calls for the manufacture of six Prometheus engine demonstrators, a process that the agency hopes will prove that the engine can be manufactured at the target recurring cost.

Initiated by French space agency CNES in 2015, the Prometheus project was adopted by ESA in 2017 under the agency’s Future Launchers Preparatory Programme.

ESA describes the project as an ultra-low cost reusable liquid methane rocket engine demonstrator designed to produce 1000 kN of thrust. A total of 70% of the mass of the engine, including the combustion chamber, will be 3D printed allowing for a tenfold reduction in costs from existing European rocket engines.



Prometheus is designed to be highly versatile enabling it to be integrated into the design of core, booster, and upper stages on Europe’s future launch vehicles. As well as an intelligent health monitoring system, Prometheus will be the first European rocket engine to feature controlled combustion.

Designed to provide control over a range between 30% and 100% of maximum thrust, the controlled combustion system will enable future European launch vehicles to adapt to flight conditions during various phases of the mission.

As the name suggests, Prometheus is expected to be the spark that ignites a push to develop more affordable rocket engines that Europe requires to ensure it can compete in the increasingly competitive global launch market.

“The knowledge we have acquired will enable us to develop lighter, much less expensive engines, making European launchers ever more competitive and environmentally friendly,” said André-Hubert Roussel, CEO of ArianeGroup.

In addition to supplying funding for the static-fire testing of the two demonstrator engines and the manufacture of six more, the new contract includes provisions for the design of a liquid-hydrogen variant of the Prometheus engine. This variant of the engine could be utilized aboard an expendable Arane 6 launch vehicle as early as 2025.

Andrew Parsonson is a space enthusiast and the founder of Rocket Rundown. He has worked as a journalist and blogger for various industries for over 5 years and has a passion for both fictional and real-life space travel. Currently, Andrew is the primary writer for Rocket Rundown as we look to expand our reach and credibility.