The crew of the Boeing CST-100 Starliner received encouraging news regarding its return to Earth. Recent ground testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has concluded. Boeing and NASA had been waiting for these tests to finalize plans for the vehicle’s homecoming.
An update indicated that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico has been completed, and teams are now reviewing the data. The main goal of the testing was to evaluate thruster degradation to better understand why some thrusters were rendered inactive during the flight and to assess the potential impact of reactivating them on the remainder of the Crew Flight Test.
When officials refer to “de-selected” thrusters, they mean that some ceased functioning. Issues arose before and during the Starliner’s launch due to leaking helium tanks that control the thrusters, resulting in several delays. During a press conference last month, it was mentioned that the spacecraft has 70 hours of helium onboard, although only seven hours are needed for operation. Earlier this month, officials stated the craft could return if necessary, but they also indicated they are not yet prepared for that to happen.
The latest announcement from NASA and Boeing suggested that a return flight could happen at the end of this month. However, the timeline has become less specific: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and will work towards finalizing 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.”