The Boeing CST-100 Starliner crew received encouraging news regarding their return to Earth. Testing of the spacecraft’s thrusters, which has kept it in space since early June, has been completed. Boeing and NASA were awaiting the results of these tests to begin planning for the spacecraft’s homecoming.
An update released late 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 the tests was to assess thruster performance and understand why some thrusters were inactive during flight, as well as to evaluate the implications of returning those thrusters to operational status for the upcoming Crew Flight Test.
When officials referred to “de-selected” thrusters, they were indicating that some of the thrusters had ceased functioning. Issues with helium tanks controlling the thrusters led to leaks before and during the Starliner launch, resulting in several delays. Although the spacecraft reportedly has 70 hours’ worth of helium onboard—far more than the seven hours needed—officials indicated that while it could return to Earth immediately if necessary, they preferred to wait for more preparations.
Previously, NASA and Boeing mentioned that a return flight could occur at the end of this month. However, the timeline is now less defined: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and finalize flight rationale in support of readiness reviews for Starliner’s upcoming return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”