The Boeing CST-100 Starliner crew has received positive news regarding its return to Earth. Recent tests on the spacecraft’s thrusters, which have been stranded in space since early June, have been successfully completed. Boeing and NASA had been awaiting the completion of these tests to start planning the vehicle’s return.
A statement released late last week indicated, “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 the tests was to assess thruster degradation to better understand the reasons behind some thrusters being deactivated during flight and to evaluate the potential impact of reactivating them on the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that ceased functioning. Before and during the Starliner launch, helium tanks controlling the thrusters experienced leaks, causing several delays. Officials stated at a press conference last month that the spacecraft has enough helium—70 hours’ worth—despite requiring only seven. They noted that while the craft could theoretically return immediately if necessary, they are not fully prepared for that eventuality.
In the most recent update, NASA and Boeing mentioned that a return flight could occur at the end of this month. However, the timeline is now less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance in finalizing flight rationale in support of readiness reviews for Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”