WASHINGTON — With the successful completion of a core stage hot-fire test, the European Space Agency says it now expects the primary launch of the Ariane 6 to happen in the midst of 2024.
At a Nov. 30 briefing, ESA Director General Josef Aschbacher announced a launch period for the inaugural Ariane 6 flight of June 15 through July 31. A more precise launch date will likely be provided after qualification reviews within the spring of 2024.
The announcement comes after a Nov. 23 long-duration test firing of a model of the core stage of the Ariane 6. That test, conducted on the launch pad at Kourou, French Guiana, was intended to simulate a full burn by the core stage.
“It became pretty clear right after the test that this was going thoroughly,” Aschbacher said, a conclusion affirmed at a gathering of an Ariane 6 task force Nov. 29, allowing ESA to set a launch date. “We’re very confident that the test was a full success.”
During that test, the core stage’s Vulcain 2.1 engine was intended to fireplace for 470 seconds. Nonetheless, the engine shut down after 426 seconds, which officials attributed to a faulty sensor and “very conservative” test thresholds intended to guard the launch pad that might not have been used on an actual launch.
“All of the objectives for the test were anyway achieved,” said Toni Tolker-Nielsen, ESA’s director of space transportation. “It didn’t change the success of the test.”
The core stage test took place after a Sept. 1 test of the Ariane 6 upper stage in Germany, which confirmed its performance in a nominal flight. “We’ve got all of the hot-fire tests that are needed for the qualification of the maiden flight,” said Martin Sion, chief executive of ArianeGroup, the prime contractor for the Ariane 6.
There are still some additional tests planned before the primary launch. One other upper stage test is scheduled for Dec. 7 in Germany to check its performance in “degraded” conditions. A fueling test of the Ariane 6 in Kourou is scheduled for Dec. 15, which can conclude with a transient ignition of the core stage engine.
Flight hardware for the primary Ariane 6 launch, called FM1, will likely be transported by ship from Europe to French Guiana, arriving in February. It should undergo final tests there, including a wet dress rehearsal, Sion said.
The primary launch will carry several small satellites. “It’s not bringing a serious payload into space,” Aschbacher said, but noted the agency desired to still use the flight as a chance for smaller satellites.
If the primary launch is successful, ESA and Arianespace will work towards a second launch before the tip of 2024. “The goal is to have a second flight by the tip of the 12 months,” said Stéphane Israël, chief executive of Arianespace. “This can be a key goal for us.” That second launch, he later said, would carry the CSO-3 reconnaissance satellite for the French military.
He said that Arianespace will seek to conduct “as many flights as possible” in 2025, including the primary launches for its largest business customer, Amazon’s Project Kuiper constellation. The long-term goal is 9 to 10 Ariane 6 launches per 12 months.
Aschbacher said the test, together with an agreement on future support for the Ariane 6 reached on the European Space Summit in Seville, Spain, Nov. 6, marked the start of the tip of a “launcher crisis” that has temporarily deprived Europe of independent access to space. That crisis, brought on by Ariane 6 delays in addition to the grounding of the Vega C after a December 2022 launch failure, has required ESA and the European Commission to show to SpaceX for launches of key science and navigation satellites.
“One shouldn’t underestimate the selections of Seville,” he said, where ESA members agreed to offer as much as 340 million euros ($370 million) a 12 months in support for the Ariane 6, authorizing the acquisition of a tranche of 27 rockets after the initial group of 15. The agreement also included support at lower levels for Vega C. “To have this access to space guaranteed now throughout the last decade, each for the Ariane 6 and the Vega C launchers, is prime.”
“It is admittedly fundamental that we regain our foothold on the launcher landscape,” he said at the tip of the briefing. “But, in fact, we’ve yet to perform.”