The Boeing CST-100 Starliner crew has received encouraging news about its potential return to Earth. Testing of the spacecraft’s thrusters, which have kept it in orbit since early June, has recently concluded. Boeing and NASA had been awaiting the completion of these tests to start planning the spacecraft’s return.
An update stated, “Ground testing of a Starliner Reaction Control System (RCS) thruster at the White Sands Test Facility in New Mexico is complete, and teams are now focusing on data reviews.” The objective of the tests was to analyze thruster degradation to understand why some thrusters were rendered inoperable during flight and to evaluate the implications of possibly reinstating those thrusters for the ongoing Crew Flight Test.
The term “de-selected” refers to thrusters that malfunctioned. During the launch, the helium tanks responsible for controlling the thrusters experienced leaks, resulting in several delays. Officials noted in a recent press conference that while the Starliner is equipped with 70 hours’ worth of helium, it only requires seven for its return. Although they mentioned earlier this month that the spacecraft is capable of returning immediately if necessary, they indicated that they are not fully prepared for such an event just yet.
In the last report, NASA and Boeing had indicated that a return flight could occur at the end of the month. However, the timeline has since become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections and move forward with 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.”