The Boeing CST-100 Starliner crew has received encouraging news regarding their return to Earth. Following the completion of ground testing for the spacecraft’s thrusters, which have left it in orbit since early June, Boeing and NASA are poised to begin planning for the vehicle’s homecoming.
An update from last week confirmed, “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 reviews.” The objective of the testing was to assess thruster degradation, aiding teams in understanding the reasons behind the in-flight deselection of some thrusters and evaluating the potential impacts of reactivating those thrusters on the upcoming Crew Flight Test.
The term “deselected” refers to the failure of some thrusters to operate efficiently. Prior to and during the Starliner’s launch, the helium tanks responsible for controlling the thrusters experienced leaks, resulting in multiple delays. At a press conference last month, officials noted that the spacecraft has 70 hours’ worth of helium on board, even though only seven hours are necessary. While they indicated earlier this month that the craft could return at any moment if required, they emphasized that preparations are still underway.
NASA and Boeing previously mentioned the possibility of a return flight at the end of this month. However, the timeframe has now become less specific: “Boeing and NASA engineers will proceed with thruster disassembly and inspections, and advance towards finalizing flight rationale to support readiness reviews for Starliner’s planned return to Earth with commander Butch Wilmore and pilot Suni Williams in the upcoming weeks.”