The Boeing CST-100 Starliner crew has received positive news regarding their return to Earth. The spacecraft has been in orbit since early June, and recent ground tests of its thrusters have been completed. Boeing and NASA had been awaiting the completion of these tests to plan for the spacecraft’s return journey.
A recent update confirmed, “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 purpose of the tests was to evaluate thruster performance and understand the reasons behind the in-flight failure of some thrusters, as well as to assess the potential impacts of reinstating those thrusters for the Crew Flight Test.
The term “de-selected” refers to certain thrusters that became inoperative. There were issues with helium tanks that control the thrusters, which leaked prior to and during the launch, resulting in multiple delays. Officials noted last month that the Starliner has 70 hours’ worth of helium onboard, even though it only requires seven hours for operations. They indicated that while the craft could technically return now if necessary, they are not yet prepared for that to happen.
In their latest update, NASA and Boeing suggested that a return flight could occur at the end of this month. However, the timeline has since become less specific, stating, “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.”