The Boeing CST-100 Starliner crew is inching closer to their return to Earth following successful ground tests of the spacecraft’s thrusters. These thrusters have kept the vehicle in space since early June, and Boeing and NASA had been waiting for the test results before making plans for the spacecraft’s homecoming.
The update released recently indicated that ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico has been completed, prompting teams to start analyzing the data. The primary goal of the testing was to assess any degradation in the thrusters to understand why some were not operational during flight and to evaluate the implications of reactivating those thrusters on the upcoming Crew Flight Test.
Officials noted that some thrusters were “de-selected,” meaning they ceased functioning. Prior to and during the Starliner’s launch, helium tanks that control the thrusters were identified as leaking, causing several delays. At a press conference last month, officials mentioned that the spacecraft has 70 hours’ worth of helium available, although only 7 hours are necessary for its operations. While they indicated earlier this month that the craft could return immediately if needed, they also stated that they are not yet fully prepared for that eventuality.
The latest communication from NASA and Boeing suggested that a return flight could occur by the end of this month. However, the timeline is now less specific, with Boeing and NASA engineers set to disassemble and inspect the thrusters. They will also work on finalizing the flight rationale in preparation for readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the weeks ahead.