The crew of the Boeing CST-100 Starliner has received encouraging news regarding their return to Earth. The recent completion of ground tests on the spacecraft’s thrusters, which have kept it in orbit since early June, has paved the way for planning its homeward journey. Boeing and NASA had been awaiting the test results to begin coordinating the return flight.
An update from last week noted, “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 analysis.” The objective of the testing was to examine thruster performance and understand the reasons behind the in-flight failures of specific thrusters, as well as the potential impact of reactivating them on the Crew Flight Test.
Officials clarified that “de-selected” refers to thrusters that stopped functioning. Prior to and during the Starliner’s launch, helium tanks used to control the thrusters experienced leaks, causing several delays. During a press conference last month, it was revealed that the spacecraft has an excess of helium onboard—70 hours’ worth, even though it requires only seven. While officials indicated earlier this month that the craft could return to Earth if necessary, they also stated that they are not fully prepared for that event just yet.
In the most recent update, NASA and Boeing suggested that the spacecraft could potentially return at the end of this month. However, the timeline has since become less specific. “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and work on finalizing flight rationale for readiness reviews regarding Starliner’s scheduled return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”