The Boeing CST-100 Starliner crew has received promising news regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which have left it stranded in space since early June, has been completed. Boeing and NASA had been awaiting the conclusion of these tests to initiate plans for the spacecraft’s homecoming.
An update provided 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 objective of this testing was to identify thruster degradation, helping the teams understand why certain thrusters failed during flight and to assess the potential impact of reactivating those thrusters on the remaining Crew Flight Test.
The term “de-selected” refers to the thrusters that ceased to function. Prior to and during the Starliner launch, tanks containing helium, which is crucial for thruster operation, experienced leaks, resulting in multiple delays. During a press conference last month, officials noted that while the spacecraft has 70 hours’ worth of helium onboard, it only requires seven hours. Although they indicated earlier this month that the spacecraft could return at any moment if necessary, there remains a sense of caution about proceeding immediately.
In the last update, NASA and Boeing mentioned that a return flight could occur by the end of this month. However, the timeline now appears less defined: “Boeing and NASA engineers will conduct thruster disassembly and inspections as they continue to finalize flight rationale to support readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”