The Boeing CST-100 Starliner crew received encouraging news regarding their return to Earth. Ground tests of the spacecraft’s thrusters, which have left it in orbit since early June, have now been completed. Boeing and NASA were awaiting the completion of these tests before initiating plans for the vessel’s return journey.
An update released last week stated, “Ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is complete, and teams are now turning their attention to data reviews.” The purpose of these tests was to assess thruster degradation to better understand why some thrusters failed during the flight and to evaluate the implications of potentially reactivating them for the Crew Flight Test.
Some thrusters were referred to as “de-selected,” indicating they had ceased operation. Issues arose from helium tanks that control the thrusters, which were found to be leaking prior to and during the Starliner launch, resulting in several delays. Officials noted last month that the spacecraft has 70 hours’ worth of helium on board, despite only needing seven. While they have stated the vehicle could return to Earth immediately if required, they also mentioned that they are not yet prepared for that eventuality.
In the latest update from NASA and Boeing, a return flight was anticipated for the end of this month, although the timeline has since become less defined. “Boeing and NASA engineers will continue with the disassembly and inspection of the thrusters and will finalize flight rationale to support readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks,” the report concluded.