The Boeing CST-100 Starliner team has received positive news regarding the spacecraft’s return home. Earth-based testing of the Starliner’s thrusters, which have left it in space since early June, has now been completed. Boeing and NASA were waiting for these tests to finalize plans for the spacecraft’s return journey.
Last week’s update confirmed that ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is finished, and efforts are shifting to data analysis. The objective of the tests was to analyze thruster performance and degradation to understand the issues leading to some thrusters being “de-selected” during flight.
The term “de-selected” refers to thrusters that malfunctioned. Issues with helium tanks, which manage the thrusters, created leaks both prior to and during the Starliner launch, causing several delays. During a press conference last month, officials stated that the spacecraft carried 70 hours’ worth of helium, though only seven hours were required for its mission. While they indicated earlier this month that the Starliner could return immediately if necessary, they also noted that they are not yet fully prepared for that eventuality.
In the latest update from NASA and Boeing, it was mentioned that a return flight could occur at the end of this month. However, the timeline is now less specific: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and work towards 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.”