The crew of the Boeing CST-100 Starliner has received promising news about their return to Earth. Recent earthbound testing of the spacecraft’s thrusters, which have kept it stranded in space since early June, has been successfully completed. Boeing and NASA had been awaiting the completion of these tests before planning the spacecraft’s return trip.
“Ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now reviewing the data,” an update last week mentioned. “The test aimed to observe thruster degradation to understand why some thrusters stopped working in-flight and what impacts returning those thrusters to service might have on the remainder of the Crew Flight Test.”
The term “de-selected” indicates that some thrusters stopped functioning. Tanks holding the helium that controls the thrusters were leaking before and during the Starliner launch, causing multiple delays. At a press conference last month, officials noted that the ship carries 70 hours’ worth of helium onboard, though it only requires seven hours. Although they stated earlier this month that the craft could return immediately if necessary, they also indicated that they are not quite ready for its return.
In the latest update, NASA and Boeing suggested that a return flight could happen by the end of this month. However, the timeframe remains somewhat vague: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and will move forward with finalizing flight rationale to support readiness reviews for Starliner’s anticipated return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”