The Boeing CST-100 Starliner team received encouraging news regarding the spacecraft’s return to Earth. Ground testing of the Starliner’s thrusters, which have kept it in space since early June, was recently completed. Boeing and NASA had postponed plans for the vehicle’s homecoming until these tests were finalized.
An update released late last week stated, “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 testing aimed to assess thruster performance degradation to understand why certain thrusters were deemed inoperable during the flight and evaluate the feasibility of reactivating them for the Crew Flight Test.
Officials indicated that some thrusters had become inoperative, with helium tanks—responsible for controlling the thrusters—leaking before and during launch, which caused several delays. During a press conference last month, officials confirmed that the Starliner is equipped with 70 hours’ worth of helium, although it only requires seven hours for operations. They noted that while the spacecraft could technically return to Earth immediately if required, preparations for such a move are not fully in place.
At the latest update, NASA and Boeing indicated that the spacecraft might complete its return flight by 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 continue finalizing the flight rationale to support readiness reviews for Starliner’s intended return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”