The crew of the Boeing CST-100 Starliner has received encouraging news regarding their return to Earth. Recently, ground testing of the spacecraft’s thrusters was completed, which has left it in orbit since early June. Boeing and NASA had awaited the results of these tests to initiate preparations for the spacecraft’s homebound journey.
An update released last week indicated, “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 aims of the tests were to examine any degradation in thrusters, providing insights into why some thrusters were inoperative during flight and determining the potential effects of returning those thrusters to operational status for the remaining Crew Flight Test.
The term “de-selected” refers to those thrusters that ceased functioning. Issues arose from leaks in the helium tanks that regulate the thrusters both prior to and during the Starliner’s launch, resulting in several delays. Officials noted last month that while the spacecraft is equipped with 70 hours of helium, it realistically only requires seven hours for its operations. Although they stated earlier this month that the Starliner could return if necessary, they also mentioned they are not fully prepared for its return just yet.
In the latest report, NASA and Boeing indicated that a return flight could potentially occur at the end of this month. However, the timeline has now become less specific: “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.”