The Boeing CST-100 Starliner crew has received encouraging news regarding their return to Earth. The completion of ground testing on the spacecraft’s thrusters, which has kept it in space since early June, marks a significant step forward. Boeing and NASA had been awaiting the results of these tests before starting to plan for the spacecraft’s journey back home.
An update released recently confirmed, “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 primary goal of these tests was to assess thruster degradation, which would help the teams understand why some thrusters were non-operational during flight and what effect restoring them might have on the upcoming Crew Flight Test.
The term “de-selected” refers to the thrusters that ceased functioning, attributed to leaks in the helium tanks that control them, which were identified both before and during the Starliner launch, resulting in a series of delays. A NASA official stated last month that the spacecraft has ample helium—70 hours’ worth—despite only needing seven hours for its operations. While they mentioned that the craft could technically return at any moment if necessary, the current readiness is still being assessed.
In their latest update, NASA and Boeing indicated that a return flight could occur by the end of this month, although the timeline has now become less specific. “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and move forward with finalizing flight rationale in support of readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”