The crew of the Boeing CST-100 Starliner has received positive news regarding its upcoming return to Earth. Recent ground tests of the spacecraft’s thrusters, which have kept it in space since early June, were successfully completed. Boeing and NASA had held off on planning for the vessel’s return trip until these tests were finalized.
An update released late last week stated, “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 goal of the testing was to analyze thruster degradation, providing insights into why some thrusters were not operational during flight and evaluating the potential effects of reactivating those thrusters on the remainder of the Crew Flight Test.
The term “de-selected” refers to those thrusters that ceased functioning. Issues with helium tanks that control the thrusters, which were leaking before and during the Starliner launch, resulted in multiple delays. Officials noted in a press conference last month that the spacecraft carries enough helium for 70 hours, despite only requiring seven. While they mentioned earlier this month that the Starliner could return now if necessary, they also indicated that they were not fully prepared for that option.
The latest update from NASA and Boeing suggested that a return flight could occur at the end of this month. However, the timeframe has since become less specific: “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.”