The crew of the Boeing CST-100 Starliner has received encouraging news regarding its return to Earth. Recently, ground testing of the spacecraft’s thrusters was completed, which had kept it in orbit since early June. Boeing and NASA had been waiting for these tests to conclude before making plans for the spacecraft’s homeward journey.
An update from last week reported, “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 purpose of these tests was to investigate thruster performance issues, particularly the malfunctioning thrusters that were deselected during flight, to assess their potential impact on the Crew Flight Test.
The term “de-selected” refers to thrusters that ceased functioning. Prior to and during the launch of the Starliner, tanks containing helium that regulates the thrusters experienced leaks, resulting in several delays. Officials indicated that while the spacecraft carries 70 hours of helium, it only requires seven hours. Although it was mentioned earlier this month that the spacecraft could head back to Earth if necessary, officials noted they are not fully prepared for that step yet.
In their most recent update, NASA and Boeing mentioned the possibility of a return flight occurring at the end of this month. However, this timeline has since become less specific: “Boeing and NASA engineers will continue with thruster disassembly and inspections while finalizing flight rationale for the readiness reviews needed for Starliner’s planned return to Earth, with commander Butch Wilmore and pilot Suni Williams in the coming weeks.”