The crew of the Boeing CST-100 Starliner has received encouraging news regarding its eventual return to Earth. Recent ground testing of the spacecraft’s thrusters, which have left it in orbit since early June, has been completed. This testing was a prerequisite for Boeing and NASA to start organizing the spacecraft’s return journey.
According to a recent update, “Ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now turning their attention to data reviews.” The testing aimed to assess the degradation of thrusters, which will help engineers understand why certain thrusters were marked “de-selected” during the flight and the implications of reactivating them for the upcoming Crew Flight Test.
The term “de-selected” indicates that some thrusters failed to operate. Prior to and during the launch of Starliner, there were issues with the helium tanks that control the thrusters, resulting in several delays. Officials noted last month that the spacecraft has enough helium on board for 70 hours, despite only needing seven. While they mentioned earlier this month that the spacecraft could return immediately if necessary, they are not fully prepared for that eventuality yet.
The latest communication from NASA and Boeing suggested that a return flight might occur by the end of this month. However, the timeline has become slightly less defined: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and move forward with finalizing flight rationale in support of readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”