The crew of the Boeing CST-100 Starliner has received positive news regarding its potential return to Earth. Recent ground testing of the spacecraft’s thrusters, which have hindered its return since early June, has been successfully completed. Boeing and NASA had been awaiting the conclusion of these tests to begin planning for the spacecraft’s homeward journey.
An update shared last week stated, “Ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is complete, and teams are now focusing on data reviews.” The purpose of the tests was to investigate thruster degradation, allowing engineers to better understand why some thrusters were disabled mid-flight and to assess the possible impacts of reactivating them on the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that malfunctioned. Prior to and during the Starliner launch, helium tanks controlling the thrusters experienced leaks, resulting in several delays. Officials mentioned last month that the spacecraft has 70 hours of helium on board, far exceeding the seven hours it typically requires. While they indicated earlier this month that the Starliner could return immediately if necessary, they noted that preparations are still ongoing.
In the most recent update, NASA and Boeing hinted that a return flight might occur at the end of this month. However, the timeline is now less certain: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and will continue 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.”