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Comment by Octoth0rpe

2 days ago

> If it's just unreliability then it might be a hard problem to solve.

It might, but it certainly helps having a ton of them around. Given that they used 42 of them today and 2 failed in some fashion, we'll call that a 1:21 failure rate. On a more typical rocket with say 10 engines (eg falcon 9), there's a good chance they wouldn't have seen the same failure till flight 3.

> Given that they used 42 of them today

20+10+3=33 on the booster, 3+3=6 on the Ship, total 39.

I remember Elon said they want to add 2 engines to the first stage, but that still would be 41. Where's the 42th supposed to be?

  • I messed up, for some reason I had it in my head that there were 9 on starship, so 33 + 9 = 42.

It’s something like up to 6 can fail and it keeps going, seems pretty good. I know they did some stuff like remove a heat tile to get failure feedback, wonder if engine was planned or accidental

  • Accidental since they didn’t make the sub-orbit they were aiming for and thus couldn’t test engine re-light.

Adjusted wald intv'l gives us for 2 observed out of 39 gives us a "true" failure rate from 1 in 200 to 1 in 6 (95% CI).