The Boeing CST-100 Starliner spacecraft may soon be heading back to Earth as ground testing of its thrusters has been completed. This testing was crucial, as the spacecraft has been stranded in space since early June. Boeing and NASA were awaiting the results to plan the return mission.
An update from late last week confirmed, “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 aim of the tests was to understand the thruster failures that occurred during flight and assess the potential impact of bringing some of these thrusters back into service.
Some thrusters were “de-selected,” meaning they failed to operate correctly. This issue was compounded by leaks in the helium tanks that control the thrusters, causing multiple delays. Recently, officials stated that while the Starliner has 70 hours’ worth of helium onboard, it requires only seven to return. Although a return could technically happen now if necessary, officials indicated they prefer to wait for proper readiness.
Previously, NASA and Boeing suggested a return flight could occur by the end of this month. However, the current timeline is 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.”