The crew of the Boeing CST-100 Starliner has received promising news regarding its return to Earth. Recently, ground testing of the spacecraft’s thrusters, which had left it stranded in space since early June, was successfully completed. Boeing and NASA had been awaiting these tests to commence plans for the vessel’s homeward journey.
An update provided late last week confirmed that the ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is finished, and teams are now focusing on analyzing the data. The testing aimed to assess thruster degradation, allowing them to understand why certain thrusters were rendered inoperable during flight, and to evaluate the potential impact of restoring those thrusters to service for the remainder of the Crew Flight Test.
The term “de-selected” refers to some thrusters stopping their operation. There were issues with the tanks containing helium that regulate the thrusters, which experienced leaks both prior to and during the Starliner’s launch, causing several delays. Officials mentioned at a press conference last month that the spacecraft is equipped with 70 hours’ worth of helium, even though only seven hours are required for its functioning. While they indicated earlier this month that the craft could return immediately if necessary, they clarified that preparations were still ongoing.
In the latest update, NASA and Boeing suggested that the return flight could occur at the end of the month. However, the timeline is now less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and continue finalizing flight rationale in support of readiness reviews for Starliner’s nominal return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”