The crew of the Boeing CST-100 Starliner has received some encouraging news regarding its return to Earth. The recent completion of ground tests on the spacecraft’s thrusters, which have kept it in orbit since early June, has enabled Boeing and NASA to begin planning the vessel’s homecoming.
A recent update 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 data reviews.” The purpose of the test was to assess thruster degradation, allowing the teams to better understand why some thrusters were inactive during the flight and to evaluate the potential impact of restoring those thrusters for the remainder of the Crew Flight Test.
The term “de-selected” refers to certain thrusters that ceased to function. Prior to and during the Starliner launch, tanks containing helium, which is essential for controlling the thrusters, were found to be leaking, resulting in several delays. At a press conference last month, officials indicated that the spacecraft was equipped with 70 hours’ worth of helium, although only seven hours are required. While they mentioned earlier this month that the craft could return at any moment if necessary, they emphasized that they are not fully prepared for it to do so just yet.
In the most recent update, NASA and Boeing suggested that a return flight could occur at the end of this month. However, the timeline has since become less clear: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and continue 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.”