Ariane 6 — Galileo’s next ride — undergoes hot-fire tests

The Ariane 6 launch vehicle program has taken a dramatic step towards first flight with the start on Oct. 5 of hot-fire tests of the rocket’s upper stage and its all-new Vinci engine, according to the European Space Agency (ESA).

The tests are a significant step forward. They are being conducted using the specially built P5.2 test bench for engine and stage testing at the German Aerospace Center (DLR) in Lampoldshausen. The P5.2 test bench subjects the entire upper stage to operating conditions representative of a flight from Europe’s Spaceport in French Guiana, with the exception of vacuum and microgravity.

New Vinci Engine

Vinci, the upper stage engine of Ariane 6 fed by liquid hydrogen and oxygen, can be stopped and restarted multiple times — a critical capability for the complex missions demanded by launch customers today.

The rocket can place several satellites into different orbits and de-orbit the upper stage, leaving a minimum of hazardous debris in space. Vinci also has been developed for reliability, simplicity and lower costs.

Replacement Heavy Launcher

This test series is a critical milestone on a development path that will soon see Ariane 6 replace Ariane 5 as ESA’s heavy launcher.

For more than a quarter century, Ariane 5 has been a reliable partner for commercial, institutional and scientific clients. One of its most notable missions was the Dec. 25, 2021, flight that carried the NASA/ESA/CSA James Webb Space Telescope to its operational outpost in deep space.

But Ariane 6 will be an even more versatile vehicle, strengthening Europe’s autonomy in accessing space.

Auxiliary Power Unit

The tests being run at Lampoldshausen are also evaluating an innovative auxiliary power unit (APU) that works in tandem with the Vinci engine and is instrumental to Ariane 6 upper-stage performance.

To restart in space, earlier engines relied on large quantities of tanked helium to generate the necessary pressure and temperature in the propellant tanks and to ensure there are no bubbles in the fuel lines. However, the APU delivers these conditions using only small amounts of the cryogenic hydrogen and oxygen already carried in the main tanks.

Heading to ESTEC

The test series is being run by DLR and ArianeGroup, the Ariane 6 launcher prime contractor. When the test series is complete, the upper stage — integrated by ArianeGroup at its facility in Bremen, Germany — will be shipped to ESA’s ESTEC technical center in the Netherlands for stage separation and acoustic tests.

Ultimately, the Lampoldshausen tests will investigate hardware behavior and system function of the complete stage with its tanks, engines and avionics.

“The preparation for these hot firing tests is even more complex than for an actual launch,” said Ariane 6 launcher program manager Guy Pilchen. “Our colleagues in Lampoldshausen have decades of experience in rocket propulsion with extremely advanced test facilities. With ArianeGroup colleagues to control the upper stage and DLR people operating the test bench, we couldn’t ask for a better team.”

Space independence for Europe

ESA Director of Space Transportation Daniel Neuenschwander said that this new engine and the upper stage it powers are indispensable components of Ariane 6 and its objective — to guarantee that Europe maintains independent, competitive and sustainable access to space.

“It’s a fact in the 21st century that Europeans depend on space for safety, prosperity and security,” Neuenschwander said. “Europe needs to work toward complete autonomy in accessing and operating in space. Ariane 6 is key to this, and we are eager to see the liftoff from Europe’s Spaceport in French Guiana.”

Ariane 6 Vinci engine testing at DLR Lampoldshausen. (Photo: ESA)