The Boeing CST-100 Starliner crew has received encouraging news regarding their return to Earth. Recent ground testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has been completed. Boeing and NASA were awaiting these tests to start planning the spacecraft’s homecoming.
An update shared last week stated, “Ground testing of a Starliner Reaction Control System (RCS) thruster at White Sands Test Facility in New Mexico is complete, and teams are now focusing on data reviews.” The purpose of the test was to analyze thruster performance degradation to understand the reasons behind some thrusters being disabled during the flight and to assess the potential implications of reactivating them.
The term “de-selected” refers to certain thrusters that ceased operation. The helium tanks controlling these thrusters experienced leaks both before and during the Starliner launch, resulting in several delays. Officials previously noted that the spacecraft holds 70 hours’ worth of helium onboard, while only requiring seven hours. Although they mentioned earlier this month that the spacecraft could return if necessary, they indicated that they are not yet fully prepared for that eventuality.
In their latest update, NASA and Boeing suggested that a return flight could be possible by the end of this month. However, the timeline is now less specific: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and will work on finalizing flight rationale for readiness reviews for Starliner’s routine return to Earth with commander Butch Wilmore and pilot Suni Williams in the weeks ahead.”