The crew of the Boeing CST-100 Starliner has received positive news regarding their return to Earth. Recent ground tests on the spacecraft’s thrusters, which have kept it in orbit since early June, have been completed. Boeing and NASA were awaiting these 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 focusing on data reviews.” The purpose of the testing was to evaluate thruster performance to understand better why some thrusters were non-functional during flight and to assess the implications of potentially restoring those thrusters for the upcoming Crew Flight Test.
The term “de-selected” refers to the thrusters that failed to operate properly. Issues arose from leaking helium tanks, which impacted the spacecraft before and during its launch, resulting in multiple delays. At a press conference last month, officials mentioned that while the Starliner has 70 hours’ worth of helium on board—significantly more than the seven hours it requires—they are not yet ready for an immediate return.
In the previous update, NASA and Boeing indicated that a return flight might occur at the end of this month. However, the timeline has since become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and continue 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.”