The Boeing CST-100 Starliner crew has received positive news regarding their anticipated return to Earth. Recent ground tests of the spacecraft’s thrusters, which have been inoperative since early June, have now been completed. Boeing and NASA were awaiting the results of these tests before strategizing for the Starliner’s homeward journey.
An update from last week noted, “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 primary goal of the tests was to assess thruster degradation, providing insights into why certain thrusters were deactivated during flight and the potential implications of reactivating them.
The term “de-selected” indicates that some thrusters ceased functioning. Prior to and during the Starliner’s launch, the helium tanks that regulate the thrusters experienced leaks, contributing to several delays. Officials mentioned at a press conference last month that the spacecraft has 70 hours’ worth of helium available, despite only needing seven. Although they stated earlier this month that a return could happen immediately if necessary, they clarified that they are not yet fully prepared for it.
In their last update, NASA and Boeing indicated that a return flight might occur by the end of this month. However, the timeframe has 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.”