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asssuber t1_j9wgqvt wrote

> They lit 31 engines, a world record.

They lit 32 engines, one shut down during the (short) static fire.

> The last time someone tried 30 they blew up four rockets in a row, the second one destroying the launch facility.

N1 is a very low standard to compare against. It's engines could not even be test fired prior to being mounted in the rocket, much less had a chance to do a full static fire like SH. Those were also the first staged combustion engines ever made, oxygen-rich on top. And the failures had more to do with the rocket than the engines themselves.

On the other end a very high standard of reliability is given by SpaceX itself. SpaceX flew Falcon Heavy five times, each firing 27 engines (plus the upper stage one) and it was 100% successful with no Merlin having a problem in any of the flights. 27 is almost the same as 30, the phantasm of N1 was slayed by SpaceX itself already.

Raptor is clearly immature and problematic if you compare it with Merlin, RD-180, Vulcan-2, etc. We have seen it's engine-rich exhaust several times and they are still tweaking the film-cooling for optimal performance, and might have other problems they haven't spoken.

Given ULA's more stringent standards (they aren't expecting to lose/scrap several test vehicles, going through dozens of engines like Spacex. They don't have engine-out capability to shrug off a few bad engines like SH), I do not see BE-4 as being less fine than Raptor.