ArianeGroup tests reusable rocket powered by 3D printed Prometheus engines
The first hot-fire test campaign of the reusable engines on the Themis launcher core stage demonstrator has taken place successfully at ArianeGroup’s Vernon (France) site
On June 22, 2023, at its Vernon site in France, ArianeGroup successfully carried out the final test in the ignition campaign of the reusable and almost entirely 3D printed Prometheus engine on the reusable Themis rocket stage demonstrator, which is being used as the test bench. The engine performed a 12-second burn.
Europe’s Ariane launcher has been powered since 1996 by the Vulcan engine. By 2030, the new Prometheus (Precursor Reusable Oxygen METHane cost Effective propUlsion System) engine will be picking up the baton. Reusable up to five times and capable of delivering variable thrust up to 100 tonnes, Prometheus will burn oxygen and methane in place of oxygen and hydrogen.
Prometheus, developed by ArianeGroup with its European partners, is a new-generation, reusable, high-thrust (100 ton) engine which runs on liquid oxygen (LOX) and liquid methane (LCH4). Among methane’s many advantages as a rocket fuel, it is cheaper, easier to handle and remains liquid at almost the same temperature as oxygen. Six times denser than hydrogen, methane will also enable more-compact rocket stages, making them easier to recover for reuse. CNES is also looking at producing methane from biomass at the Guiana Space Centre.
This test campaign consisted of firing the Prometheus engine on Themis, as the test bed. The successful ignition of Prometheus is a first in Europe for this class of engine. For this campaign, ArianeGroup used bio-methane fuel, in line with the company’s aim of trail-blazing environmental innovation.
Faster and cheaper
From an economic perspective, Prometheus is aiming to reduce production costs tenfold with respect to the currently used Vulcan engine—which has a unit cost of €1 million—thanks to a different architecture, extensive use of 3D printing and a production rate of 50 engines per year. From a schedule perspective, the goal is to equip the lower (with the Themis demonstrator) and upper stages of Europe’s future range of launchers—from micro-launchers to Ariane Next—by 2030.
Themis is a reusable rocket stage demonstrator for which ArianeGroup is the lead contractor. Two years after the contract for the initial phase of Themis was signed with ESA, this first combined test campaign with the Prometheus engine is a key step in the progress of the project. It paves the way for the next test campaign, to be carried out at Kiruna in Sweden, under the European Union’s Horizon Europe program (SALTO project).
Prometheus and Themis are part of European Space Agency (ESA) programs for which ArianeGroup is the lead contractor. This test campaign was carried out within a short time frame thanks to the support of France Relance, for which the French space agency CNES is the space component operator. The Prometheus engine and the reusable Themis stage are central to Europe’s strategy for preparing its future launchers.
Prometheus was conceived and designed by CNES and ArianeGroup between 2015 and 2017. Responsibility for the program was handed over to the European Space Agency (ESA) at the Ministerial Conference in Lucerne in December 2016. ESA has tasked ArianeGroup with developing Prometheus and CNES is supporting the agency on project oversight, notably as Technical Officer on the joint ESA/CNES team. CNES is also participating as an industry partner to pool the best talents and experience with a view to pushing the limits of disruptive innovation for the Prometheus project.
Getting up to speed
“This successfully concluded test campaign marks a first concrete step for development of reusable launchers built in Europe. The complete test of the Prometheus engine, carried out directly on the reusable Themis stage demonstrator, has been particularly eagerly anticipated as it opens up highly promising avenues for the future family of European launchers. The campaign at Vernon was made possible by the close collaboration of the teams from ArianeGroup, ESA, and CNES, and the support of France Relance,” said Martin Sion, CEO of ArianeGroup.
Carrying out these tests on Prometheus and Themis together on the PF20 test bench at Vernon will allow characterization of the operating behavior of both engine and stage in an extended mission profile. Prometheus engine testing will continue at the end of 2023 on the German Aerospace Center (DLR) test bench at Lampoldshausen, Germany.
ArianeGroup will soon be setting up a Prometheus Users Club, along the lines of the Ariane 6 Users Club. This step marks the beginning of marketing Prometheus to all interested European parties.
