The Boeing CST-100 Starliner crew has received encouraging news regarding their impending return to Earth. The recent completion of ground testing for the spacecraft’s thrusters, which have prevented it from returning since early June, has allowed Boeing and NASA to start planning its return journey.
An update released last week 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 shifting their focus to data reviews.” The testing aimed to assess thruster degradation to better understand why some thrusters malfunctioned during flight and to evaluate the potential impact of reactivating these thrusters on the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that have failed to operate. The helium tanks responsible for controlling the thrusters experienced leaks before and during the Starliner’s launch, leading to several delays. Despite having 70 hours’ worth of helium onboard—far more than the seven hours required—officials indicated last month that although the spacecraft could return if necessary, they are not fully prepared for that eventuality.
Previously, NASA and Boeing suggested that a return flight might occur at the end of this month. However, the timeframe has since become less definite: “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.”