The Boeing CST-100 Starliner crew has received promising news regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has been completed. Boeing and NASA were awaiting the results of these tests to begin preparations for the spacecraft’s homecoming.
An update provided last week indicated that the tests on the Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico are finished. Teams are now focused on reviewing the data collected. The purpose of the test was to assess thruster degradation, which will help the teams understand why some thrusters were inactive during flight and evaluate the potential impacts of reactivating those thrusters on the upcoming Crew Flight Test.
Some thrusters were labeled as “de-selected” because they ceased functioning. Prior to and during launch, the helium tanks that control the thrusters experienced leaks, which resulted in several delays. Officials stated last month that the spacecraft carries 70 hours’ worth of helium onboard, but only requires seven for its operation. While they noted earlier this month that the Starliner could return immediately if necessary, they also indicated that they are not fully prepared for that scenario.
According to the latest update, NASA and Boeing mentioned that a return flight might occur by the end of this month. However, the timeline has since become less certain: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance in finalizing flight rationale to support readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”