The crew of the Boeing CST-100 Starliner received encouraging news regarding their return to Earth. Recently completed ground tests of the spacecraft’s thrusters, which have kept it in orbit since early June, have marked a critical step forward. Boeing and NASA were awaiting these test results to initiate plans for the vehicle’s homecoming.
An update released 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 turning their attention to data reviews.” The primary aim of the tests was to investigate thruster performance, particularly to understand why certain thrusters were not operational during flight and to assess the consequences of potentially reactivating them.
The term “de-selected” refers to thrusters that became inoperative. Prior to and during the Starliner launch, there were issues with helium tanks controlling the thrusters, resulting in several delays. Officials reported last month that the spacecraft has 70 hours’ worth of helium onboard, even though only seven hours are needed for its operations. While they stated earlier this month that the Starliner could return immediately if necessary, readiness for such an action remains uncertain.
The latest update from NASA and Boeing suggested that a return flight might occur at the end of this month. However, the timeframe now appears more indefinite: “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 coming weeks.”