The crew of the Boeing CST-100 Starliner has received promising news regarding its return to Earth. Recent ground tests of the spacecraft’s thrusters, which have kept it in space since early June, have been successfully completed. Boeing and NASA were awaiting these test results to start planning for the spacecraft’s homecoming.
An update from 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 purpose of these tests was to analyze thruster performance and understand why certain thrusters were inoperative during flight, along with evaluating the implications of bringing those thrusters back into service for the upcoming Crew Flight Test.
“De-selected” refers to some thrusters that malfunctioned. Prior to and during the Starliner launch, there were leaks in the helium tanks that control these thrusters, causing multiple delays. Officials mentioned last month that the spacecraft has 70 hours of helium on board, while it only requires seven for its operations. Although they indicated that the craft could return at any moment if necessary, they also noted that they are not quite ready for that eventuality.
In their most recent update, NASA and Boeing mentioned that a return flight might occur at the end of this month. However, the timeline is now less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and continue with finalizing flight rationale to support readiness reviews for Starliner’s anticipated return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”