Boeing Starliner thruster ground testing complete, data reviews underway
[Starliner docked at the International Space Station (NASA)]
The ground team in charge of the Boeing Starliner spacecraft recently completed an important Starliner Reaction Control System (RCS) ground thruster testing at the White Sands Test Facility in New Mexico and is currently reviewing data that may have been collected during the test. They used similar new thrusters that have flown during the recent Starliner flight, which is still currently docked to the International Space Station, waiting for its approval to return to Earth with two crew astronauts onboard, commander Butch Wilmore and pilot Suni Williams. According to Boeing, the objective of the test was to understand thruster degradation to see why some thrusters were deactivated while en route towards the International Space Station during the recent launch of the Starliner Crew Flight Test 1 (CFT-1). They also hoped to observe what impacts may happen if they return those deactivated thrusters to service during the remainder of the flight test itself, specifically during the return of the spacecraft with its crew.
The new, similar thruster underwent rigorous testing which included launch-to-docking firing sequences with over 1,000 pulses to simulate what the damaged thrusters faced during the CFT. Conditions such as manual flying and rendezvous with the International Space Station were included during this first phase. The second phase went through five undock-to-deorbit burn pulses with over 500 pulses. After this nominal phase, the team decided to make the thruster undergo longer and more frequent pulses, which were simulating higher than normal thermal conditions experienced in flight. This was to ensure that the firings would replicate more the thrust degradation it went through during the mission, which should lead to more additional learnings about the real limits of the thruster even if they already recorded tons of data during the nominal phases of testing.
The reason why they are currently doing these tests though aside from safety purposes is because they want to make sure that they can learn about the issues that the propulsion system is currently experiencing before proceeding with the return to Earth. These testing should take them a longer time to return but it will help the engineers to improve the spacecraft as a whole for future missions. The propulsion system is placed at the service module of the spacecraft, which is currently expendable, and should mean that engineers cannot inspect the service module back on Earth as it should have burnt up during re-entry. Therefore, the problem will be lost at re-entry and engineers cannot have a chance to learn about the current issues. That's why they have decided to replicate the problem on the ground first and learn about it, before actually proceeding with the return of the spacecraft back to Earth.
With the successful testing that happened on the ground, the teams should have successfully replicated the thrust degradation on the ground, the same issue that the main spacecraft that is docked to the ISS is currently experiencing. After this test, Boeing and NASA engineers should now proceed with the disassembly of the tested thruster to inspect what the thruster went through the testing. As they inspect this thruster and give their conclusions on what happened during the test, they hope to finalize the flight rationale in support of readiness reviews for Starliner's return to Earth with its two crew, commander Butch Wilmore and pilot Suni Williams in the coming weeks. The reason why they are currently doing theseUpdates on the progress will be provided by NASA’s Commercial Crew Program Manager Steve Stich and Boeing Starliner Program Manager Mark Nappi during a media telecom in the future. Currently, NASA and Boeing still haven't decided on when the Boeing Starliner and its crew will have a normal return to Earth. However, Starliner is cleared for a return to Earth when a major emergency happens aboard the International Space Station, which we all hope doesn't happen.
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This is KYNNMASTER 123 for The Weekly Spaceman, see you in the next one! 😊
Resources and credits (and photos):
1. https://x.com/BoeingSpace/status/1814016671956279370 (Boeing)
2. https://starlinerupdates.com/starliner-thruster-ground-testing-complete-data-reviews-underway/ (Boeing)
