The crew of the Boeing CST-100 Starliner has received encouraging news regarding their return journey to Earth. Recent ground tests of the spacecraft’s thrusters, which have left it in orbit since early June, have been completed. Boeing and NASA were waiting for these tests to finalize plans for the spacecraft’s return.
The testing of the Starliner Reaction Control System (RCS) thrusters took place at the White Sands Test Facility in New Mexico. An update released last week indicated that teams are now focused on reviewing the data collected during the tests. The primary objective was to assess any degradation of the thrusters to better understand why some thrusters were not operational during the flight and to evaluate the impact of potentially reaccommodating those thrusters for the Crew Flight Test.
Officials clarified that “de-selected” refers to the thrusters that had ceased functioning. Issues arose with helium tanks controlling the thrusters, which were found to be leaking both prior to and during the Starliner launch, causing several delays. During a press briefing last month, officials mentioned that while the spacecraft has a reserve of 70 hours’ worth of helium, it only requires seven hours for its operation. Although they stated earlier this month that the craft could return immediately if necessary, they also acknowledged that they were not fully prepared for that scenario.
In the latest update, NASA and Boeing indicated that a return flight could be scheduled for the end of this month. However, the timeframe is now more uncertain as the engineers continue with thruster disassembly and inspections. They are working toward finalizing the flight rationale to support readiness reviews for the Starliner’s eventual return to Earth, which will carry commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.