The Boeing CST-100 Starliner crew has received encouraging news regarding their future return to Earth. Ground testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has been completed. Boeing and NASA awaited the results of these tests to start planning the spacecraft’s return journey.
An update released late last week revealed, “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.” This testing aimed to examine thruster degradation and understand why some thrusters were inactive during the flight, as well as to assess the implications of reactivating those thrusters on the upcoming Crew Flight Test.
The term “de-selected” refers to thrusters that ceased functioning. Prior to and during the Starliner’s launch, helium tanks that control the thrusters experienced leaks, contributing to multiple delays. During a press conference last month, officials indicated that the spacecraft carries 70 hours’ worth of helium, despite only requiring seven hours. They noted that while the craft could return immediately if necessary, they are not yet fully prepared for its homecoming.
In the latest update, NASA and Boeing suggested that a return flight might occur at the end of this month. However, the timeline has now shifted to a more indefinite schedule: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and will move forward with finalizing flight rationale to support readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”