The Boeing CST-100 Starliner crew has received some optimistic news regarding their eventual return to Earth. Recent ground tests of the spacecraft’s thrusters, which have kept it in orbit since early June, have now been completed. Both Boeing and NASA were waiting for these tests to plan the spacecraft’s homecoming.
A recent update confirmed, “Ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is complete, and teams are now focusing on data reviews.” The goal of the testing was to examine the degradation of thrusters to understand why some were deactivated during flight and to assess the implications of reactivating them for the upcoming Crew Flight Test.
When officials refer to “de-selected,” they indicate that certain thrusters became non-functional. It was noted that the helium tanks controlling the thrusters had been leaking both before and during the launch of Starliner, which caused several delays. In a press conference last month, officials mentioned that the spacecraft has 70 hours’ worth of helium onboard, although it only requires seven. They stated earlier this month that the Starliner could return to Earth if necessary, but they are not fully prepared for that to happen just yet.
In their last update, NASA and Boeing indicated that a return flight might occur by the end of this month. However, the timeline has now become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and will continue to finalize flight rationale in preparation for readiness reviews regarding Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”