The Boeing CST-100 Starliner crew has received promising news regarding its return to Earth. Recent ground testing of the spacecraft’s thrusters, which have left it in orbit since early June, has been completed. Boeing and NASA were waiting for these tests to plan the vehicle’s return.
An update provided last week stated, “Ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now focusing on reviewing the data.” The tests aimed to investigate thruster degradation and to understand why some thrusters were not operational during flight, as well as to assess the implications of potentially reactivating those thrusters.
The term “de-selected” refers to the thrusters that ceased functioning. Issues arose with helium tanks controlling these thrusters leaking before and during the Starliner launch, causing several delays. Previously, officials mentioned that the spacecraft carries 70 hours’ worth of helium, despite needing only seven. While they indicated earlier this month that the craft could return immediately if required, there’s still some hesitation about proceeding with a return.
In their last update, NASA and Boeing suggested a possible return flight at the end of this month. However, this timeline has become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and will 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.”