The crew of the Boeing CST-100 Starliner received encouraging news regarding their return to Earth. Recent testing of the spacecraft’s thrusters, which have left it in orbit since early June, has been completed. Boeing and NASA were waiting for the results of these tests to start preparations for the craft’s journey home.
An update released last week 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 purpose of the testing was to assess thruster performance degradation to understand the issues that caused some thrusters to stop working during flight and any potential impacts of restoring those thrusters to operation on the overall mission.
Some thrusters had been “de-selected,” a term used by officials to indicate they ceased functioning. Issues with helium tanks that control the thrusters led to delays before and during the Starliner’s launch. Officials noted that the spacecraft carries 70 hours’ worth of helium, despite only requiring seven. While they mentioned earlier this month that it could return home if necessary, they also indicated they are not yet fully prepared for that eventuality.
In their latest update, NASA and Boeing suggested that a return flight might happen at the end of this month; however, the timeline has since become less specific. “Boeing and NASA engineers will proceed with thruster disassembly and inspections and advance their efforts to finalize the flight rationale in support of readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks,” they stated.