The Boeing CST-100 Starliner has received promising news regarding its imminent return to Earth. Recently, ground tests for the spacecraft’s thrusters, which have left it orbiting since early June, were successfully completed. Both Boeing and NASA had been awaiting these tests to begin outlining the Starliner’s homeward journey.
An update shared 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 reviewing the data.” The purpose of the test was to analyze why some thrusters malfunctioned during flight and to consider the implications of potentially reactivating them for the Crew Flight Test.
The term “de-selected” refers to the thrusters that ceased functioning. Prior to and during the Starliner launch, there were leaks in the helium tanks that control these thrusters, causing several delays. Officials indicated at a recent press conference that the spacecraft contains 70 hours’ worth of helium, although only seven hours are required for its operation. They mentioned that while the spacecraft could technically return to Earth at this moment, they prefer to wait until they are fully prepared.
Previously, NASA and Boeing indicated a possible return flight could happen by the end of this month. However, the timeline has now shifted to a more uncertain forecast: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and will move forward with 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 coming weeks.”