The Boeing CST-100 Starliner crew has received encouraging news regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which have prevented it from returning since early June, has been successfully completed. Boeing and NASA were waiting for these tests to finish before making plans for the spacecraft’s return journey.
Last week, an update 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 primary aim of the tests was to assess the degradation of the thrusters to understand why some of them ceased functioning during flight and to evaluate the potential impacts of returning those thrusters to service on the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that stopped operating. Prior to and during the Starliner launch, there were issues with the helium tanks that control the thrusters, which resulted in multiple delays. Officials noted that the spacecraft is equipped with 70 hours’ worth of helium, despite only requiring seven hours. While they indicated earlier this month that the craft could return immediately if necessary, they also expressed that it is not yet fully prepared for its return.
In their most recent update, NASA and Boeing mentioned that a return flight could be possible by the end of this month, although the timeline has since become less specific. “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and will move forward with finalizing flight rationale in preparation for readiness reviews for Starliner’s eventual return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks,” they stated.