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 have kept it in orbit since early June, has been completed. Boeing and NASA awaited the outcome of these tests to begin planning for the Starliner’s return journey.
Last week, an update confirmed that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico was finished, and teams are now reviewing the data collected. The objective of the tests was to evaluate thruster degradation, enabling a better understanding of why some thrusters were de-selected during flight and assessing the potential impacts of bringing those thrusters back into service.
The term “de-selected” refers to thrusters that ceased functioning. It was noted that helium tanks controlling these thrusters experienced leaks both before and during the launch of the Starliner, leading to multiple delays. At a press conference last month, officials indicated that the Starliner has 70 hours’ worth of helium on board, although only seven hours are necessary for its operations. While they mentioned earlier this month that the spacecraft could return to Earth immediately if required, they clarified that preparations for a return are not yet fully complete.
In their latest communication, NASA and Boeing suggested that a return flight could occur by the end of this month, but the timeline has since become more uncertain. They stated that Boeing and NASA engineers will continue with the disassembly and inspection of the thrusters, as well as finalize the flight rationale necessary for readiness reviews related to Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the forthcoming weeks.