The Boeing CST-100 Starliner crew has received promising news regarding their return home. Recent ground tests on the spacecraft’s thrusters, which have left it stranded in space since early June, have been successfully completed. Boeing and NASA were waiting for these tests before outlining the plan for the spacecraft’s journey back to Earth.
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 reviewing the data.” The primary goal of the tests was to assess thruster performance degradation, helping the teams understand the reasons behind some thrusters being deselected during flight and the potential impacts of restoring those thrusters to service on the overall Crew Flight Test.
The term “deselected” refers to some thrusters that failed to function. Before and during the launch, the tanks containing helium for thruster control were found to be leaking, which led to several delays. Officials indicated that while the spacecraft currently has 70 hours of helium onboard, only seven hours are necessary. Although it was previously mentioned that the Starliner could return immediately if necessary, the team clarified that they are not yet fully prepared for that scenario.
The last update from NASA and Boeing suggested that a return flight could occur at the end of this month, but the timeline is now more uncertain. The statement continued, “Boeing and NASA engineers will proceed with the disassembly and inspection of the thrusters and move forward with finalizing the 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.”