The crew of the Boeing CST-100 Starliner received encouraging news regarding its return to Earth. Recent testing of the spacecraft’s thrusters, which have prevented it from returning since early June, has been completed. Boeing and NASA were awaiting the results of these tests to start organizing the vessel’s homeward journey.
An update released last week indicated, “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 turning their attention to data reviews. The test aimed to observe thruster degradation to better understand the reasons behind some thrusters being deactivated during flight, as well as any potential impacts of returning those thrusters to service on the overall Crew Flight Test.”
The term “de-selected” refers to the fact that certain thrusters became non-operational. Prior to and during the Starliner launch, helium tanks that control the thrusters were found to be leaking, causing multiple delays. Officials noted last month that the spacecraft carries 70 hours’ worth of helium, despite only requiring seven. While they mentioned earlier this month that the Starliner could return if necessary, they also stated that it is not quite ready for that step.
In their latest communication, NASA and Boeing indicated that a return flight could potentially occur at the end of this month. However, the timeline has since become less defined: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance in 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.”