The Boeing CST-100 Starliner crew has received positive news regarding their spacecraft’s impending return to Earth. Recent tests of the spacecraft’s thrusters, which have left it in orbit since early June, have been completed. Boeing and NASA were awaiting these results to begin preparing for the vehicle’s homecoming.
According to an update released last week, “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 focusing on data reviews.” The tests aimed to investigate thruster performance issues to understand why some were inactive during the flight and assess potential impacts of reactivating them.
The term “de-selected” refers to thrusters that malfunctioned. Prior to and during the Starliner’s launch, there were leaks in the helium tanks that regulate the thrusters, resulting in several postponements. Officials noted in a press conference last month that the Starliner has 70 hours’ worth of helium, while only seven are necessary for its operation. While they indicated earlier this month that the spacecraft could return if required, they also stated that they were not fully prepared for that scenario.
The latest information from NASA and Boeing suggested that a return flight could occur at the end of this month. However, the timeline has since become less specific: “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.”