The Boeing CST-100 Starliner crew has received promising news regarding their return to Earth. Recent ground tests of the spacecraft’s thrusters, which have kept it in orbit since early June, have now been completed. Both Boeing and NASA had been awaiting the results of these tests to begin formulating plans for the spacecraft’s homeward journey.
A statement from last week indicated, “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 analysis.” The purpose of the testing was to assess thruster performance degradation to understand the reasons behind the failure of some thrusters during the flight and any potential effects of reintegrating those thrusters into the system for the Crew Flight Test.
The term “de-selected” refers to the failure of certain thrusters to operate. Prior to and during the Starliner’s launch, leaks were discovered in the tanks containing the helium that mobilizes the thrusters, causing several delays. Officials noted last month that the spacecraft has 70 hours’ worth of helium available, although it only requires seven for its operations. While they mentioned earlier this month that the craft could return if necessary, they affirmed that they are not quite ready for that eventuality just yet.
In their latest update, NASA and Boeing suggested that a return flight might occur by the end of this month, though the timeframe has now become less specific: “Boeing and NASA engineers will move forward with thruster disassembly and inspections, and will finalize plans for flight justification in support of readiness reviews for Starliner’s intended return to Earth, with commander Butch Wilmore and pilot Suni Williams in the weeks ahead.”