The crew of the Boeing CST-100 Starliner has received promising news regarding their return to Earth. Recently completed ground testing of the spacecraft’s thrusters, which have kept it in space since early June, has now laid the groundwork for planning its journey home. Both Boeing and NASA awaited the completion of these tests before moving forward with return flight preparations.
An update from last week revealed that testing of a Starliner Reaction Control System (RCS) thruster was successfully conducted at the White Sands Test Facility in New Mexico. The objective of these tests was to observe the degradation of thrusters, aiming to understand issues that caused some thrusters to be de-selected during flight and to assess how returning those thrusters to service could affect the overall Crew Flight Test.
The term “de-selected” refers to thrusters that ceased functioning. Prior to and during the launch, the helium tanks responsible for controlling the thrusters were identified as leaking, resulting in several delays. During a press conference last month, officials noted that the Starliner has 70 hours’ worth of helium on board, despite typically requiring only seven hours. Although officials indicated earlier this month that the spacecraft could return immediately if necessary, they also mentioned they are not yet fully prepared for that eventuality.
In their latest update, NASA and Boeing indicated that a return flight could potentially occur by the end of this month. However, the timeline has since become less precise: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and continue 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.”