The crew of the Boeing CST-100 Starliner received encouraging news regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which had kept it in space since early June, has been completed. Both Boeing and NASA were waiting for these tests to be finalized before planning the spacecraft’s journey back home.
The update confirmed that tests on a Starliner Reaction Control System (RCS) thruster were conducted at the White Sands Test Facility in New Mexico. Following the tests, teams are now focused on reviewing the data collected. The objective of the tests was to assess thruster performance issues and understand the reasons behind the failure of certain thrusters in-flight, as well as the implications of reintegrating them for the Crew Flight Test.
Some thrusters were “de-selected,” meaning they became non-functional. The helium tanks used to control the thrusters experienced leaks both before and during the Starliner launch, which caused multiple delays. Officials noted at a press conference last month that the spacecraft has 70 hours of helium onboard, although it only requires seven. While they stated earlier this month that the Starliner could return home immediately if necessary, they indicated that further preparations are needed before that occurs.
The most recent update from NASA and Boeing suggested that a return flight could take place at the end of this month. However, the timeline has since become less specific: “Boeing and NASA engineers will continue with the disassembly and inspection of the thrusters and will move forward to finalize the flight rationale in preparation for readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”