Asking this one less than an hour after the event? Gonna be a while before this one gets answered.

The rapid unscheduled disassembly seemed to happen before the stage separation.

Note that (unlike for example Aviation where this is forbidden), asking about incidents that are still under investigation is allowed here. But, of course, the question might not be answerable until the incident report is finalized and published which can take from several weeks to several years.

@JörgWMittag I have time to wait for the answer. I was watching the live stream I was waiting for separation. The a big cloud appears on the screen and it is announced the the self destruct system has been activated. I just had to ask why it failed even if it might take a bit for an answer

We should not ask questioners to guess when an answer might be available. Let them ask interesting questions as soon as they are thought of, as long as it is reasonable to suppose that they will have an answer.

@WayneConrad your comment reminds me of this space.meta.stackexchange.com/questions/1407/…

I would say that multiple engines out during first stage means it didn't go normally.

The massive crater below the OLM might have had something to do with that, @OrganicMarble.

The boosters didn't cut off when they should have, so that would seem to indicate some sort of control system failure. Maybe there was more heat or vibration than they anticipated?

@OrganicMarble Starship doesn't need all 33 to launch.

@RonJohn seemingly unproven at this point.

@OrganicMarble seeming proven by the fact that it was accelerating with only 28 engines lit.

@RonJohn sure, it worked out great.

@OrganicMarble you know full well that rockets have failed to reach orbit for reasons beyond "the main engines didn't have enough thrust".

33 needed to launch, no, 33 needed to succeed, yet to be seen. Though at this point these should probably be moved to chat

I’m voting to close this question because the cause is currently unknown. By the time the cause becomes known the question will become pointless as the answer will be all over the internet.

@TheRocketfan I have explicitly voted to close this question using "Other". By the time the answer is known, which will takes months of people time, it will either be all over the internet (in which case this becomes an irrelevant question), or it will be known only to people who have "need to know" (in which case this will remain an unanswerable question) with the official explanation being a bit fuzzy. Either way, asking for an explanation of a failure less than an hour after the failure occurred is premature.

We know what the maximum speed was achieved by Super Heavy. But I could not find online what the target speed was supposed to be before separation. I am asking because the performance of Super Heavy apparently was less than nominal, even with 4-5 engines out.

@TheMatrixEquation-balance it reached maxQ, it would have reached maxQ too even if it hopped 10m high only. The value of max pressure it reached is just far below the expected value it should withstand when all engines run