The crew of the Boeing CST-100 Starliner has received positive news regarding their imminent return to Earth. Recently, ground testing of the spacecraft’s thrusters, which have been inactive since early June, was successfully completed. Boeing and NASA had been awaiting these test results to begin formulating the plans for the Starliner’s homecoming.
An update from 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 aim of the testing was to investigate thruster degradation, helping engineers understand why some thrusters failed during flight and the potential effects of restoring them to service on the crewed mission.
The term “de-selected” refers to those thrusters that ceased functioning. The helium tanks that regulate the thrusters experienced leaks before and during the Starliner launch, causing several delays. Officials mentioned at a recent press conference that the spacecraft has 70 hours of helium available on board, despite only needing seven hours for its operations. Although it was stated earlier this month that the Starliner could return immediately if necessary, readiness for that move is still not fully established.
In their latest update, NASA and Boeing indicated that a return flight could occur at the end of October. However, the timeline is now less specific, as plans are underway for thruster disassembly and inspections. Engineers will work on finalizing the flight rationale for the Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.