The crew of the Boeing CST-100 Starliner has received promising news regarding their return to Earth. Recent ground tests of the spacecraft’s thrusters have finished, as the Starliner has remained in space since early June. Boeing and NASA had waited to initiate plans for the spacecraft’s return until these tests were completed.
An update released last week stated, “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 purpose of these tests was to examine thruster degradation and to understand why some thrusters malfunctioned during flight, as well as the potential effects of returning those thrusters to service for the Crew Flight Test.
The term “de-selected” refers to some thrusters that failed to operate. Prior to and during the Starliner launch, there were leaks in the helium tanks that control the thrusters, leading to multiple delays. Officials mentioned last month that the Starliner has 70 hours of helium onboard, despite only requiring seven hours. While they indicated that the spacecraft could return home immediately if necessary, they also acknowledged that it is not fully prepared for the journey yet.
In the latest update, NASA and Boeing suggested that a return flight could potentially occur at the end of this month. However, the timeline is now less specific: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and will work towards finalizing the flight rationale in preparation for readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”