The European Space Agency is postponing the final flight of the original version of the Vega rocket due to a problem with the rocket’s upper stage. In a Dec. 14 briefing following the ESA Board of Directors meeting, agency officials said the next and final launch of the Vega rocket, previously planned for spring 2024, had been postponed until September due to a lack of tanks for the upper stage of the Avum rocket.

European Spaceflight reported on December 4 that two tanks built for Avum’s final upper stage disappeared from an Italian factory used by the rocket’s prime contractor, Avio, during repairs at the facility. The steps were reportedly later found crushed and unusable in a dump.

“Avio confirmed to ESA that there was a problem with the tanks on Vega’s last flight,” said Toni Tolker-Nielsen, ESA’s director of space transport. He did not confirm details of the problem with the tanks but said the tanks were not stolen. He said the new September launch date was based on “an interim solution for these missing tanks.”

ESA and Avio evaluated two solutions. One was to use tanks originally built for Vega qualification over a decade ago. This will make a launch possible in July. “But such a decision is risky,” he said, as the tanks may not pass repeated tests before being launched.

One option the agency would likely adopt is the use of tanks for the larger Avum+ stage of the Vega C rocket. “This will require some structural changes to Avum’s internal structure,” he said. “It seems like a good, workable solution.” This approach will support Vega’s September 2024 launch.

This latest Vega mission previously aimed to launch the Biomass Earth science satellite for ESA. Sentinel-2C, another earth science spacecraft that is part of the Copernicus program, is currently scheduled for launch. Simonetta Cheli, director of ESA’s Earth Observation Division, said ESA had not yet identified a new Biomass launch opportunity.

The problem with the latest Vega has nothing to do with ongoing efforts to return Vega C to service after a failed launch nearly a year ago. Following two Zefiro-40 second stage static fire tests of the vehicle with the redesigned nozzle, the next launch of the Vega C is currently planned for mid-November to mid-December, Tolker-Nielsen said.

In the briefing, Tolker-Nielsen said there was also a problem during testing of the Ariane 6 upper stage on December 7. The purpose of these hot fire tests at a German facility was to analyze the operation of the upper stage in adverse conditions. .

“Unfortunately, we had a two-minute break from the shooting test,” he said. ArianeGroup, the rocket’s main contractor, is investigating the cause of the accident. The issue does not currently affect Ariane 6’s initial launch schedule, which has been announced for June 15 – July 31, 2024.

Another wet rehearsal of the Ariane 6 test model, called Combined Test Payload 3, is planned for Dec. 15 at the spaceport in Kourou, French Guiana, he said. This test will end with a brief start of the main engine.