Avatar2go wrote:ZaphodHarkonnen wrote:Perhaps not as smoothly as expected or wanted. 2 thrusters shut down unexpectedly during the insertion burn. The FCS was able to adapt but still not a good look at all.
https://www.theverge.com/2022/5/19/2313 ... nasa-oft-2Today, the thruster firing seemed to go well initially, and Starliner is in its intended orbit. However, after the flight, Boeing revealed that two thrusters actually failed during the orbital insertion, shutting down earlier than intended. The first shut down after one second, and the flight control system rerouted to a second thruster nearby. However, that one also shut down early after just 25 seconds, and the system had to reroute to a third thruster, which worked as intended. All in all, it didn’t affect Starliner’s ability to reach its planned orbit. Boeing is studying the issue, though the company and NASA claim the failed thrusters should not impact Starliner’s ability to perform the rest of its mission.
To clarify from the post-launch media briefing, there are 12 OMAC thrusters distributed between 4 doghouses. In the port doghouse, 2 of the thrusters had early shutdowns, but the 3rd was ok. Starliner has levels of redundancy that include the loss of any one doghouse, with the others compensating. The RCS thrusters can also suffice in a pinch. It was not necessary to invoke those scenarios.
They are reviewing the data to understand the early shutdowns on the 2 thrusters, and may be able to recover them in flight. They mentioned that it could be an instrumentation or software setting issue.
Overall the flight is still nominal and there are no concerns about the mission at all. There are 4 more OMAC burns scheduled, 3 before the docking and 1 for de-orbit. All could also be done with RCS if that became necessary.
I appreciate your comments on here, they are clear, concise, with a level of detail that is interesting, but not overwhelming with tech jargon. Oh and without a level of hysteria, just reporting the details, Thanks.