The crew of the Boeing CST-100 Starliner has received encouraging news regarding its return to Earth. Recent ground testing of the spacecraft’s thrusters, which have been inactive since early June, has concluded. Boeing and NASA were awaiting the completion of these tests to start planning for the spacecraft’s return journey.
An update shared 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 focusing on data reviews.” The tests aimed to examine thruster degradation to understand the reasons why some thrusters were deactivated during flight and assess the implications of potentially restoring those thrusters for the Crew Flight Test.
The term “de-selected” refers to several thrusters that malfunctioned. Prior to and during the Starliner launch, there were leaks in the tanks containing helium that regulates the thrusters, resulting in various delays. Officials mentioned last month that the spacecraft is equipped with 70 hours of helium, despite only needing seven. While they indicated that the spacecraft could return to Earth immediately if necessary, they also noted that it isn’t yet fully prepared for the return.
In the latest update, NASA and Boeing suggested that a return flight could take place at the end of this month. However, the timeline has now become more ambiguous: “Boeing and NASA engineers will continue with thruster disassembly and inspections while finalizing flight rationale in preparation for readiness reviews for Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”