The crew of the Boeing CST-100 Starliner has received positive news regarding its return to Earth. Recently, ground testing of the spacecraft’s thrusters was completed, which had kept the Starliner in space since early June. Boeing and NASA had been awaiting the completion of these tests before starting to plan for the spacecraft’s return journey.
Officials announced that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico was finished, and teams are now focused on reviewing the data. The objective of the test was to assess the thruster’s performance and understand why some thrusters were inactive during flight, as well as the potential effects of reactivating them on the overall crew flight test.
During flight, some thrusters were identified as “de-selected,” meaning they stopped functioning. This issue was compounded by leaks in the helium tanks that control the thrusters both before and during launch, resulting in several delays. At a press conference last month, officials stated the Starliner has sufficient helium onboard—70 hours’ worth—despite only needing seven for its operation. Although they indicated earlier this month that the spacecraft could return if necessary, they also mentioned that they are not yet fully prepared for the return.
The latest update from NASA and Boeing suggested a potential return flight at the end of this month. However, the timeline is now less specific. Boeing and NASA engineers will continue with thruster disassembly and inspections and are moving forward to finalize the flight rationale necessary for readiness reviews, paving the way for Starliner’s eventual return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.