SpaceX is switching out one of the three Raptor engines on its Starship SN10 prototype, likely pushing the vehicle's high-altitude test flight back a bit.
The swap decision was made yesterday (Feb. 23), shortly after SN10 ("Serial No. 10") ignited its engines for the first time during a "static fire" test at SpaceX's South Texas facilities.
"One of the engines is suspect, so we’re swapping it out," company founder and CEO Elon Musk said via Twitter yesterday.
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The static fire was part of SN10's prep work for a roughly 6-mile-high (10 kilometers) test hop into the Texas skies, which could have happened as early as Thursday (Feb. 25). The engine swap will probably delay the flight a bit, but it's unclear how much; Musk did not mention a new timeline.
SN10 will be the third Starship prototype to fly so high. The SN8 and SN9 vehicles performed similar flights on Dec. 9, 2020, and Feb. 2, respectively. Both flew well until the end, checking off many milestones before crashing at the landing zone.
Like SN10's, SN9's path to flight included an engine swap. SpaceX replaced two of SN9's three engines after the vehicle performed three static fires in rapid succession on Jan. 13.
SpaceX is developing Starship to get people and cargo to the moon, Mars and beyond. The system consists of two reusable elements: a 165-foot-tall (50 meters) spacecraft called Starship and a giant rocket called Super Heavy. The final Starship will have six Raptors, and Super Heavy will be powered by about 30 of the engines, Musk has said.
SpaceX wants a Starship prototype to make an orbital test flight sometime this year. And Musk recently said that he thinks the final vehicle will be operational by 2023.
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.