The crew of the Boeing CST-100 Starliner has received positive news regarding their upcoming return to Earth. Testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has recently been completed. Boeing and NASA were awaiting the completion of these tests before starting to plan for the vessel’s journey home.
An update shared 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 focused on reviewing the data.” The purpose of the tests was to investigate thruster degradation, helping teams understand why some thrusters were deactivated during flight and whether reactivating them would affect the remainder of the Crew Flight Test.
“De-selected” refers to the thrusters that ceased functioning during the mission. Prior to and during the Starliner launch, leaks in the helium tanks that control the thrusters contributed to several delays. During a press conference last month, officials mentioned the spacecraft has 70 hours of helium onboard, despite only needing seven. While they indicated that the craft could return now if necessary, they clarified that they are not fully prepared for its return just yet.
In their latest update, NASA and Boeing suggested that a return flight might occur at the end of the month. However, the timeline has become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and will advance with finalizing flight rationale in anticipation of readiness reviews for Starliner’s eventual return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”