The Boeing CST-100 Starliner crew has received promising news regarding the spacecraft’s return journey to Earth. Recent ground tests on the spacecraft’s thrusters were successfully concluded, which had kept the vessel in orbit since early June. Boeing and NASA had been awaiting these test results to begin preparations for the Starliner’s homecoming.
An update from last week 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 focusing on reviewing the data.” The test aimed to assess thruster performance, particularly to understand the reasons behind some thrusters being inactive during flight and the potential effects of reactivating them.
The term “de-selected” refers to thrusters that malfunctioned. Issues arose from helium tanks used to control the thrusters, which experienced leaks before and during the Starliner’s launch, causing multiple delays. At a press conference last month, officials mentioned that the spacecraft contains 70 hours’ worth of helium, while only seven hours are necessary for its operation. Although they indicated earlier this month that the Starliner could return at any moment if necessary, they stated they are not yet fully prepared for that to happen.
In the latest update, NASA and Boeing noted that a return flight could potentially occur by the end of this month. However, the timeline is now described as more ambiguous: “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 upcoming weeks.”