Design review for Ariane’s Prometheus engine

A depiction of the Prometheus engine.

IN a press statement on February 4, the ArianeGroup said that on February 1 its ambitious future engine Prometheus passed its definition review. Prometheus, a programme of the European Space Agency (ESA) initiated with the French space agency, CNES (Centre National d’Etudes Spatiales), is a demonstrator for a very low-cost and potentially reusable engine for Ariane’s next-generation launch vehicles. The engine, according to the ArianeGroup, is a precursor of the future engines intended for use by Europe’s launchers by 2030. “It demonstrates the pertinence of the design and the technological choices made and confirms the programme’s ambitious cost objectives,” said the statement.

The contract awarded to the ArianeGroup by the ESA in December 2017 covers the design, construction and testing of the first two examples of the engine demonstrator, which uses liquid oxygen and methane as propellants. The innovative technologies and industrial processes developed for this programme will also be used for the propulsion upgrades of Ariane 6, the company stated. “This successful milestone of Prometheus programme shows that the teams at ArianeGroup and their partners [CNES and the German space agency, DLR] were able to create an innovative design in an extremely short period of time, barely one year after contract signature with ESA. This success demonstrates the pertinence of our technological choices and confirms the ambitious cost objectives we set for ourselves,” said Andre-Hubert Roussel, CEO, ArianeGroup.

According to the company, the goal of the Prometheus demonstrator is to be able to build future liquid propellant engines in the 100 tonne thrust class at a cost 10 times less than that involved in building existing engines such as the Vulcain. The cost of Vulcain 2.1, for example, is around 10 million euros. The cost of launching 1 kg into the geostationary transfer orbit by current Ariane launchers is $10,000. Prometheus engine-based launchers are expected to bring that down to $5,000/kg.

Over and above the switch from the traditional liquid oxygen and hydrogen combination to liquid oxygen and methane, the engine has other major changes such as digitisation of engine control and diagnostics and construction using 3D printing in a connected factory environment.

The next major milestone of the programme is the production of two demonstrators in the first half of 2019. The bench tests of these first two prototypes are scheduled for as early as 2020, which will be conducted at the DLR.