The Boeing CST-100 Starliner crew has received encouraging news regarding their anticipated return to Earth. Ground tests on the spacecraft’s thrusters, which have kept it in orbit since early June, have recently concluded. Boeing and NASA were awaiting the completion of these tests to start planning the return trip.
In a recent update, it was announced that “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 reviewing the data.” The purpose of the testing was to analyze thruster degradation to understand why certain thrusters malfunctioned during flight and assess the implications of reactivating them for the Crew Flight Test.
The term “de-selected” refers to those thrusters that ceased functioning. Issues arose due to leaks in the helium tanks that control the thrusters prior to and during the Starliner’s launch, resulting in several delays. Officials indicated that the spacecraft has 70 hours of helium available, although it only requires seven hours. They mentioned earlier this month that the vessel could theoretically return right now if necessary, but they also expressed that they are not fully prepared for that.
The last update from NASA and Boeing suggested that a return flight could occur by the end of this month. However, the timeline is now less definitive: “Boeing and NASA engineers will continue with thruster disassembly and inspections, and advance toward finalizing the flight rationale for readiness reviews in support of Starliner’s upcoming return to Earth, with commander Butch Wilmore and pilot Suni Williams aboard in the coming weeks.”