The crew of the Boeing CST-100 Starliner has received positive news regarding its return to Earth. Earth-based tests of the spacecraft’s thrusters, which have kept it in space since early June, have recently been completed. Boeing and NASA were awaiting these tests to begin organizing the spacecraft’s journey home.
An update from last week confirmed the successful ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico, and teams are now focused on analyzing the data. The purpose of the tests was to assess thruster degradation and to understand the reasons behind the in-flight de-selection of certain thrusters, as well as the potential impacts of reactivating them on the Crew Flight Test.
“De-selected” refers to thrusters that malfunctioned. Leaks in the helium tanks that control the thrusters contributed to multiple delays before and during the Starliner’s launch. Officials announced last month that the spacecraft has 70 hours of helium on board, far exceeding the seven hours it requires. Although they indicated earlier this month that the ship could potentially return immediately if necessary, they also stated it is not quite ready for that move yet.
In the most recent update, NASA and Boeing mentioned that a return flight might occur at the end of this month. However, the timeline has become less clear: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and will continue finalizing flight rationale to support readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”