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0 pointsappreciatorBus4mo ago0 comments

It depends on whether or not, at the point in which you realize you have an engine on fire, you have room on the runway left to stop.

As I understand it, there is a low speed regime, under 80 knots, where are you stop for basically anything.

Then there is a high speed regime, where you only stop for serious issues, because you now have so much kinetic energy that stopping the plane, while still possible, will involve risk. (i.e. fire from overheated brakes.)

At a certain point, called V1, there’s no longer enough room to stop, no matter what your problem is. You’re either getting airborne or you’re crashing into whatever is ant the end of the runway. In general, getting airborne is the safer option, while obviously still not risk free.

However, this calculation also assumes that the engine fails in an isolated fashion, and its failure did not affect the other engines. If the failure of the left engine threw off debris that damaged the middle engine then we are now talking about a double engine failure. I’m sure the pilots knew there was a problem with the engine when they made the decision to continue, but it’s possible that problems with the middle engine weren’t apparent yet and that it only started to fail once they were committed.

Obviously, this is just speculation, and we will have to wait for the preliminary report at least.

RIP

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bathtub3654mo ago

Being untrained but spending a little bit of time in a full motion 737 simulator that’s used to train and certify commercial pilots, I was amazed at how quickly things happen even in a scenario with no faults.

This situation (single engine failure at V1) is something that commercial pilots are certified in at every recurrent certification since it’s one of the most difficult you can be in. The crew now need to climb and go around for a landing on one engine while simultaneously running through the engine failure (and also likely fire) checklist. I don’t know if a double engine failure at V1 on a fully loaded 3 engine aircraft is technically survivable or if it’s something that’s trained on. They were put in an incredibly difficult situation just based on what reports we’ve already seen.

TheOtherHobbes4mo ago

I would be astounded if there was anything the pilots could have done to prevent this.

The plane was two engines out and a main fuel tank on fire, fully laden with a full fuel load. No amount of training or improvisation was going to fix that.

If anything it's lucky/professional they crashed into an industrial park and didn't have time for a go around. It would have been an even bigger disaster if they'd crashed into the town centre or a residential area.

loeg4mo ago

> I don’t know if a double engine failure at V1 on a fully loaded 3 engine aircraft is technically survivable

Not on the MD-11, anyway.

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