The Boeing CST-100 Starliner team has received positive news regarding the spacecraft’s return journey to Earth. Testing of the spacecraft’s thrusters, which have been inactive since early June, has recently concluded. Both Boeing and NASA had been awaiting the results of these tests before proceeding with plans for the Starliner’s homecoming.
An update shared last week indicated, “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 data reviews.” The aim of these tests was to evaluate thruster performance and understand the failures that led to some thrusters being inactive during flight.
The term “de-selected” refers to certain thrusters that ceased functioning. Issues with helium tanks that control these thrusters caused leaks before and during the launch of Starliner, resulting in several postponements. At a recent press conference, officials noted that the spacecraft is equipped with 70 hours’ worth of helium, despite only needing seven. While they stated that the vessel could return immediately if necessary, they also mentioned that they are not fully prepared for the return just yet.
In the last update, NASA and Boeing indicated that a return flight might occur at the end of this month. However, the timeline has become less defined: “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 planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”