The team behind the Boeing CST-100 Starliner has received encouraging news regarding its return to Earth. Recent ground tests on the spacecraft’s thrusters, which have been in orbit since early June, have been successfully completed. Boeing and NASA had been awaiting these tests to commence planning for the craft’s return journey.
An update shared 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 turning their attention to data reviews.” The purpose of the tests was to investigate thruster performance and understand why certain thrusters were inactive during flight, and to assess the potential impact of reactivating them on the upcoming Crew Flight Test.
The term “de-selected” refers to the thrusters that became non-functional. Issues arose from helium tanks that were leaking prior to and during the launch, which caused several delays. Officials mentioned last month that the Starliner has a total of 70 hours of helium onboard, even though only seven hours are required for its operation. While they stated earlier this month that the spacecraft could return immediately if necessary, they clarified that they are not fully prepared for that eventuality just yet.
In their most recent update, NASA and Boeing indicated that a return flight was possible by the end of this month. However, the timeframe is now less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance towards finalizing flight rationale in support of readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”