Ariane 6 hot-fire test: the replay

On 23 November 2023, in preparation for its first flight, Ariane 6 went through its biggest test to date: a full-scale rehearsal that meant complex fuelling, a launch countdown and ignition of the core stage Vulcain 2.1 engine, followed by over seven minutes of engine burn that covered the entire core stage flight phase, just as would happen during a real launch into space.

The engine roared into action after a slight anomaly meant there was a suspenseful pause to the automated sequence, before the countdown was reset and began to tick again. The live feed continued until just after core stage operations were complete and the engine had burnt through all of its propellant.

For this rehearsal the boosters were not ignited, so the Ariane 6 test model stayed firmly on the launch pad at Europe’s Spaceport in French Guiana. This was the longest ‘full-stack’ run performed to date for the rocket’s liquid propulsion module with a Vulcain 2.1 engine.

The Vulcain 2.1 engine burnt through almost 150 tonnes of propellant supplied from the Ariane 6 core stage tanks – liquid oxygen and liquid hydrogen – supercooled to temperatures below -250°C.

With thousands of monitors situated around the launchpad, the data from this rehearsal will be analysed meticulously and used for Ariane 6’s next and first real flight.