The Boeing CST-100 Starliner crew has received promising news regarding their return to Earth. Earth-based testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has recently concluded. Boeing and NASA were awaiting the completion of these tests before initiating plans for the spacecraft’s journey back home.
An update from last week announced, “The ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now turning their attention to data reviews.” The primary goal of the testing was to assess thruster degradation to better understand why some thrusters failed during flight and what impact reinstating those thrusters could have on the upcoming Crew Flight Test.
Some thrusters were designated as “de-selected,” meaning they ceased to function. Prior to and during the Starliner’s launch, the tanks containing helium for the thrusters experienced leaks, resulting in multiple delays. Officials mentioned last month that the spacecraft has 70 hours’ worth of helium available, even though it only requires seven hours for operations. While they indicated earlier this month that the Starliner could return to Earth if necessary, it appears they are not yet fully prepared for that scenario.
In the latest communication, NASA and Boeing mentioned a possible return flight by the end of this month. However, the timeline has shifted to a more flexible approach: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and move forward with finalizing flight rationale in support of readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”