The Boeing CST-100 Starliner crew has received encouraging news regarding their journey back to Earth. Recent ground tests on the spacecraft’s thrusters, which have been operationally inactive since early June, have been completed. This testing was a prerequisite for Boeing and NASA to start organizing the spacecraft’s return trip.
An update reported that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico has wrapped up, with teams now focused on reviewing the collected data. The goal of the tests was to assess thruster performance issues that led to some thrusters being rendered inoperative during flight, as well as to evaluate the implications of potentially reactivating those thrusters for the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that failed to function as intended. Before and during the launch, helium tanks responsible for controlling the thrusters experienced leaks, resulting in multiple delays. Officials noted last month that the vessel has a substantial amount of helium onboard—70 hours’ worth—despite only requiring seven. While they stated that the Starliner could return immediately if necessary, they emphasized that they are not yet fully prepared for the return.
In their last update, NASA and Boeing suggested that a return flight could occur at the end of the month. However, the timeline has become less specific: “Boeing and NASA engineers will continue with disassembly and inspections of the thrusters, moving forward with the finalization of flight rationale to support readiness reviews for Starliner’s safe return to Earth with commander Butch Wilmore and pilot Suni Williams in the forthcoming weeks.”