The crew of the Boeing CST-100 Starliner has received positive news regarding its potential return to Earth. Recent ground tests of the spacecraft’s thrusters, which have prevented it from returning since early June, have been successfully completed. Boeing and NASA were awaiting these results to start planning the spacecraft’s homeward journey.
An update released 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 turning their attention to data reviews.” The aim of the testing was to understand the degradation of some thrusters, which were not operational during flight, and to assess any potential impacts of reactivating them for the Crew Flight Test.
Some thrusters were described as “de-selected,” meaning they ceased functioning during the mission. Issues arose with helium tanks that control the thrusters, leading to delays before and during the launch. Officials have noted that the spacecraft contains 70 hours’ worth of helium, significantly more than the seven hours required. While they indicated that the Starliner could return anytime if necessary, they clarified that preparation for that return is still ongoing.
In their latest update, NASA and Boeing suggested that a return flight could have been scheduled for the end of this month. However, the timeline is now less certain: “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.”