9.01.2026

As part of a European Space Agency study, ArianeGroup has proposed an evolution of its Ariane 6 heavy-lift rocket that would utilise reusable boosters derived from the first stage of the rocket being developed by its subsidiary, MaiaSpace.

In late 2024, ArianeGroup was selected alongside Isar Aerospace for the European Space Agency’s Boosters for European Space Transportation (BEST!) initiative, which aims to foster the development of future reusable rocket first stages or boosters. The contracts awarded to the two companies covered the development of their respective proposals from Phases 0/A through B1, encompassing mission identification, feasibility studies, preliminary definition, and preliminary design.

While the results of this phase of the project have not been published, a paper presented at the European Conference for Aeronautics and Space Sciences in 2025 outlined a number of European efforts towards reusability and included a brief description of each of the two BEST! proposals.

The Isar Aerospace proposal focused on a reusable first stage that would be integrated into its Spectrum launch system. ArianeGroup’s submission proposed an evolution of Ariane 6 that would substitute the rocket’s solid-fuel expendable boosters with boosters that could be recovered and reused. According to the paper, the company proposed using boosters derived from the first stage of the small launch vehicle being developed by MaiaSpace.

According to the European Space Agency, a decision on whether to fund future rounds of the BEST! initiative was taken at the agency’s Ministerial Council meeting in November 2025. While no specific funding allocations for BEST! have been disclosed, the Reusability Element of the Future Launchers Preparatory Programme, under which the initiative is likely to sit, received subscriptions totalling €81.28 million.

ArianeGroup’s proposal is a version of a concept that the company first presented in 2022 as one of several potential future evolutions of Ariane 6. At the time, the company explained that a Liquid Reusable Booster (LRB) could replace the P160C solid-fuel booster as a “plug-and-play” alternative that would reduce operating costs and increase launch rates. According to a press release at the time, the LRBs would have been derived from the Themis reusable booster demonstrator, which ArianeGroup is developing under an ESA contract, with additional funding from the European Union.

While MaiaSpace is leading the development of its two-stage Maia rocket, ArianeGroup is responsible for upgrades to the rocket’s first stage that will enable recovery and reuse. The project, known as SkyHopper, is funded by the French government, with ArianeGroup acting as prime contractor and MaiaSpace serving as a subcontractor and launch operator.

Quelle: European Spaceflight