The Boeing CST-100 Starliner crew has received some positive news regarding their return to Earth. Recent testing of the spacecraft’s thrusters, which have kept it in space since early June, has been completed. Boeing and NASA were awaiting these test results to start planning for the spacecraft’s journey back.
An update from last week indicated that ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico was finalized, and the teams are now focused on reviewing the data. The primary goal of the testing was to analyze thruster degradation, allowing teams to better understand the issues that caused some thrusters to deactivate during flight, and to evaluate any potential effects of reintegrating those thrusters into service for final preparations of the Crew Flight Test.
The term “de-selected” refers to some thrusters that ceased functioning. Before and during the Starliner launch, the helium tanks controlling the thrusters were leaking, which led to several delays. Officials revealed at a press conference last month that the spacecraft carries 70 hours’ worth of helium, despite only needing seven. Although they stated that the ship could technically return now if necessary, they indicated that they are not yet fully prepared for that.
In the latest update, NASA and Boeing mentioned that a return flight could be possible by the end of this month. However, that timeline has since become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and move forward with finalizing flight rationale in support of readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”