New ESA Contracts to Advance Prometheus and Phoebus Projects

Prometheus rocket engine (Credit: ArianeGroup Holding)

PARIS (ESA PR) — ESA is forging ahead with advanced developments in two flagship space transportation demonstration projects, Prometheus and Phoebus. This will benefit Europe’s new Ariane 6 launcher in the near-term, and prepare for a new generation of European launch vehicles in the next decade.

Daniel Neuenschwander, ESA Director of Space Transportation, André-Hubert Roussel, CEO at ArianeGroup and Pierre Godart, CEO at ArianeGroup in Germany signed contracts worth €135 million for Prometheus and €14.6 million for Phoebus, during a virtual online ceremony.

The signing of these contacts represents an important milestone in development for both projects which will now focus on key technologies and processes defined so far in the lead up to valuable demonstrations.

“To secure Europe’s autonomous access to space at affordable costs, ESA is engaging resolutely in the development of new technologies required for future space transportation solutions. The Prometheus reusable engine and the Phoebus upper stage are excellent examples of this,” commented Daniel Neuenschwander.

Prometheus is an ultra-low cost reusable rocket engine demonstrator fuelled by liquid methane. It is highly versatile and therefore suitable for use on core, booster and upper stages of Europe’s future launch vehicles.

It features variable thrust, multiple ignitions, and intelligent onboard control systems for reusability. Thanks to additive layer manufacturing, which accounts for 70% of the mass of the engine, the number of parts is low and this speeds up production and reduces waste. This can achieve a tenfold reduction in costs compared with the existing Ariane 5 Vulcain 2 engine. In addition, the use of liquid methane fuel is expected to reduce the cost of ground operations before and after flight.

To complete the current initial phase, two existing full-scale Prometheus engine demonstrators will perform static fire tests at the DLR German Aerospace Center in Lampoldshausen, Germany. Data collected from these tests will provide important insights to validate and demonstrate the engine concept. This will feed into designs to increase engine thrust from its current 1000 kN to 1200 kN.

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

Six Prometheus engine demonstrators will be manufactured for tests. At the same time, this will prove that the engine can be manufactured at the target recurring cost.

The project will also prepare a Prometheus concept based on liquid hydrogen fuel which will provide alternative options to methane and could be available for use on Ariane 6 as early as 2025.

Phoebus is a highly-optimised upper stage for use on future versions of the upcoming Ariane 6 launch vehicle as well as other launchers. Phoebus could boost Ariane 6’s payload capacity to geostationary orbit by more than two metric tonnes and reduce production costs.

ArianeGroup will work with MT Aerospace to validate key technologies of Phoebus developed with support from ESA since May 2019.

This will enable the final phase to completion with the detailed design, build and test of a near full-scale demonstrator which will consist of an oxygen propellant tank, a hydrogen propellant tank, the interface structure between the two tanks and the outside cylinder representative of the upper stage outer skin. All of these structures will be made with carbon-fibre composite. A host of additional features will make this demonstrator a representative test bed for multiple promising technologies.

Early prototypes will de-risk the production of the full demonstrator and determine the industrialisation of the process for the series production of upper stages.

Additional technologies in the fields of materials and structures, propulsion and avionics, could use Phoebus as a ‘test bed’ opportunity to raise their technology readiness level. 

These activities are carried out within ESA’s Future Space Transportation programme.