The Boeing CST-100 Starliner crew has received a promising update regarding their return to Earth. Recently, ground tests of the spacecraft’s thrusters were completed, which had kept the Starliner in space since early June. Boeing and NASA were waiting for these tests to finish before planning the vehicle’s return.
A statement from last week noted, “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 reviewing the data.” The objective of the test was to analyze thruster degradation to understand the reasons behind some thrusters being deselected during flight and the potential impact of reinstating them on the overall Crew Flight Test.
“Deselected” indicates that some thrusters ceased functioning. Prior to and during the Starliner’s launch, the helium tanks that control these thrusters experienced leaks, resulting in several delays. In a press conference last month, officials mentioned that the spacecraft is equipped with 70 hours of helium but only requires seven for its return. Although they stated earlier this month that the Starliner could come back immediately if necessary, they also indicated that they are not fully prepared for that eventuality just yet.
In the latest update, NASA and Boeing indicated that a return flight might occur at the end of this month. The timeline now appears less certain, with plans for the next steps outlined: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance 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.”