The Boeing CST-100 Starliner crew has received promising news regarding its return to Earth. Recent ground testing of the spacecraft’s thrusters, which have left it stranded in space since early June, has been concluded. Boeing and NASA awaited the completion of these tests to initiate planning for the vehicle’s homeward journey.
An update released last week noted, “Ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now focusing on data reviews.” The primary goal of the tests was to analyze thruster degradation to gain insight into why some thrusters were deselected during flight, as well as to assess the implications of potentially returning those thrusters to service for the Crew Flight Test.
“Deselected” refers to thrusters that failed to function properly. Prior to and during the Starliner launch, there were issues with tanks leaking helium, causing multiple delays. Officials stated at a press conference last month that the spacecraft has 70 hours’ worth of helium onboard, although it only requires seven. While they indicated earlier this month that the Starliner could be brought back to Earth immediately if necessary, they also clarified that they are not fully prepared for that transition just yet.
In the latest update from NASA and Boeing, it was mentioned that a return flight could happen at the end of this month. However, the timeline has become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and will continue finalizing flight rationale to support readiness reviews for Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”