The Boeing CST-100 Starliner crew has received encouraging news regarding their return to Earth. Recently, ground tests of the spacecraft’s thrusters were completed, which had been preventing it from returning since early June. Boeing and NASA had been awaiting the conclusion of these tests before planning the spacecraft’s homecoming.
An update provided last week confirmed that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico has been finalized, and teams are now focused on analyzing the collected data. The testing aimed to assess thruster degradation, providing insights into why some thrusters failed during flight and the potential implications of reactivating them for the Crew Flight Test.
Some thrusters were “de-selected,” meaning they malfunctioned. Prior to and during the Starliner launch, there were issues with leaks in the helium tanks that control the thrusters, resulting in multiple postponements. During a press briefing last month, officials noted that the spacecraft has 70 hours of helium on board, far exceeding the seven hours it requires. Earlier this month, they stated that while the Starliner could return immediately if necessary, they still do not feel fully prepared for that eventuality.
In their latest update, NASA and Boeing mentioned that a return flight could be scheduled for the end of this month. However, the timeline has now become more uncertain: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and proceed with finalizing flight rationale to prepare for readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”