The crew aboard the Boeing CST-100 Starliner received encouraging news regarding their return to Earth. Recently, ground testing of the spacecraft’s thrusters was completed after being stuck in space since early June. Boeing and NASA had been awaiting the conclusion of these tests before planning the vehicle’s homecoming.
An update noted, “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 aim of the tests was to assess thruster degradation, which would help analyze why some thrusters were deemed inoperable during flight and understand any potential effects of returning those thrusters to service.
The term “de-selected” refers to thrusters that ceased functioning. Prior to and during the Starliner launch, helium tanks controlling the thrusters experienced leaks, resulting in multiple delays. Officials reported that the spacecraft has 70 hours’ worth of helium onboard, far surpassing the necessary seven hours. Although they indicated last month that the spacecraft could return home if necessary, they also stated they are not fully prepared for that scenario just yet.
In a previous update, NASA and Boeing suggested that a return flight could happen by the end of this month. However, the timeline has become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance to finalize 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.”