The crew of the Boeing CST-100 Starliner is starting to see potential progress regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which have kept it in space since early June, has been completed. Boeing and NASA were awaiting these results before planning for the spacecraft’s journey back home.
An update indicated, “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 focused on data reviews.” The purpose of the tests was to investigate thruster performance issues that led to some being deactivated during flight and to understand the implications of potentially reactivating them for the upcoming Crew Flight Test.
The term “de-selected” refers to the malfunction of certain thrusters. There were leaks in the helium tanks that control these thrusters, which caused several delays prior to the Starliner’s launch. Officials reported last month that the spacecraft carries 70 hours of helium, despite only requiring seven. While they indicated earlier this month that the spacecraft could return if necessary, they also acknowledged that they are not fully prepared for that return just yet.
In their most recent update, NASA and Boeing mentioned that a return flight might be feasible by the end of this month. However, the timeline is now less certain, with an announcement stating: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and continue to finalize flight rationale in support of readiness reviews for Starliner’s return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”