ArianeGroup begins testing the prototype of the multi-role Susie upper stage
BREMEN, Germany – ArianeGroup has begun testing what it sees as a versatile answer to many of the challenges facing European spaceflight.
ArianeGroup has quietly begun testing a small demonstration model of the Smart Upper Stage for Innovative Exploration (SUSIE) in recent weeks. The vehicle was announced at the International Astronautical Congress in September 2022, but little has been heard about the internally funded project.
Testing of a two-meter-tall, 100-kilogram jet-engined prototype began in October with its first ignition at the ArianeGroup site in Les Mureaux, according to an initial French-language media report.
The project aims to strengthen European independence in spaceflight by developing capabilities for both cargo and human transportation. It also “aims to enable competitive, innovative and flexible space logistics for Europe, in the context of highly diverse and growing space applications,” according to a recent post on the company’s LinkedIn page.
ArianeGroup described the 1/6 scale “test and learn” demonstration as “the first tangible step in ArianeGroup’s roadmap to quickly master and leverage the fundamental technologies needed to validate the concept, particularly during the low-speed flight, approach and landing phases.”
The full-size Susi, which is 12 meters long and five meters wide and has a payload capacity of seven tons, is designed for launch atop an Ariane 64 rocket. It can instead carry five astronauts, seated one behind the other and facing forward toward the tip of the spacecraft. Susi also aims to be fully reusable, which could reduce long-term costs and increase mission efficiency.
Parachute and abort tests are scheduled, and jump testing with the demonstrator is expected to continue until the second quarter of 2025, said Marco Wolf, program director for future projects and human spaceflight at ArianeGroup. Space news At Space Tech Expo Europe in Bremen, Germany, on November 16.
Early aircraft tests are guidance and navigation tests, while rocket-powered landing and drop tests are planned for the future. The spacecraft aims for a precision landing using its engines or a parachute.
Wolf says the development team is focusing on hands-on, hardware-based testing rather than just theoretical or paper-based methods. This includes building a demonstration model of landing approaches and conducting drop tests to evaluate the parachute system and water landing capabilities. A half-sized mock-up of two seats and a temporary design of the control panel were on display at the exhibition.
Wolf says a team of about 20 people, based in both France and Germany, are currently working on the project. Consultations were also held with European astronauts in Cologne and Airbus on human-machine interaction.
The team will look at a range of issues including sound pressure generated by rocket engines, astronaut accommodation, and the durability of the thermal protection system. The crew version of the Susi will not have an escape turret, but will likely carry solid rocket motors on the outside of the vehicle for an emergency crew escape system.
The European Space Agency recently announced a commercial cargo competition at this month’s Space Summit in Seville, Spain, which aims to stimulate the development of cargo carrying capacity with the potential to return within Europe. The half-sized Susi payload will meet requirements for delivering at least two tons of pressurized cargo to the International Space Station, and returning at least one ton to Earth.
Although specific dates and budget numbers are not available, the timeline for a smaller commercial shipping version of Susie could be ready for 2028, meeting the deadline set by the European Space Agency for the European Reusable Shipping System competition. The system will be intended to serve the International Space Station and possibly Starlab and commercial space stations.
The spacecraft design is intended to be scalable without major changes to its aerodynamic values. Wolf says manned missions will likely occur in the early 2030s.
In addition to providing human spaceflight capabilities to Europe, it could bring greater independence and autonomy, Wolf says. It will also add value by keeping money spent within Europe rather than paying others to transport cargo and crew, while also building capacity, experience and expertise.
Europe is currently re-evaluating the broader geopolitical and strategic goals of the European space sector, as evidenced by the openness to commercial modes of spaceflight. The role SOSI will play, if any, will depend on technical progress and how Europe defines, selects and supports its strategic space ambitions.