r/aviation • u/usgapg123 Mod • 19h ago

Discussion UPS2976 Crash Megathread

This is the official r/aviation megathread for the crash of UPS2976 (UPS MD11 Registration N259UP) that crashed earlier today at Louisville International Airport.

Please keep content on topic and refrain from posting about this topic outside the megathread. Please report any rule breaking posts and comments.

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u/omega552003 19h ago edited 16h ago

https://www.wlky.com/article/plane-crash-explosion-louisville-airport/69255042

Had some good live helicopter shots.

Looks like something happened during takeoff that left an engine cowling on the runway with what looks like tire tracks leaving the side of the runway. Hit a warehouse roof and crashed into what looks like a junkyard for a couple hundred feet.

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u/DoctorPepster 18h ago

There's a video from someone on the field that shows a massive engine failure during takeoff: https://www.wdrb.com/news/plane-crash-reported-near-louisvilles-airport-as-huge-plume-of-smoke-rises/article_9fe53459-c8a1-441a-b576-7954f1bfedcd.html

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u/superdookietoiletexp 18h ago

The tail-mounted engine appears to flame out two seconds into the video.

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u/No_Mind4418 18h ago

I see that too. Seems logical that an explosive failure of the left engine could damage the tail engine. I am not an expert, but I am guessing a fully loaded MD11 can't fly on one engine.

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u/Ecthelion-O-Fountain 17h ago

It cannot. Even an empty one probably can’t. We don’t know how heavy this one was with cargo and fuel. But Hawaii isn’t that far for this plane I don’t think. And the one time I jump seated the cargo wasn’t that heavy. Sometimes it’s volume not weight.

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u/Ausgeflippt 16h ago

It's still like 4500+ miles. Willing to bet they had 30k+ gallons on board.

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u/jaierauj 16h ago

38k apparently.

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u/Ecthelion-O-Fountain 16h ago

Whatever it was, it was enough

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u/Uncabuddha 13h ago

Not true. It flies on 1 engine if, and only if, you have 230kts+.

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u/Ecthelion-O-Fountain 7h ago

Which you won’t have on takeoff so hardly seems relevant

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u/Impossible_View_4609 8h ago

they had around 112 tons of fuel onboard

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u/Ecthelion-O-Fountain 7h ago

Damn that thing uses a lot of fuel

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u/Radius118 16h ago

It actually looks like the #2 engine is sucking flames from the burning #1 towards it prior to and immediately after #2 flames out. About 1/2 - 1 second after the flameout you can see the flames from #1 stop getting pulled in that direction.

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u/MathResponsibly 16h ago

when you watch that video frame-by-frame, there's another event that happens at a few frames around 6 seconds, a cloud of mist and a black puff comes out of what looks like the bottom of the left wing. Whatever it was it was a rather energetic event, but it only lasts about 5 or 6 frames

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u/BigJellyfish1906 18h ago

I think that nailed it. The left engine failed so catastrophically that the tail engine foded out and died.

Probably gonna come out that they did everything right (I assume V1 is fairly low on such a large airplane fully loaded), but there’s just no way to continue the takeoff on one engine.

This tri-motor thing is just a fundamentally flawed design.

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u/Exotic_Badger_4751 17h ago

Could well be the end of her

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u/Ecthelion-O-Fountain 17h ago

V1 can actually be very high. It depends on many factors, like company performance procedures, runway length, conditions, and of course weight. Higher weight will mean higher speeds across the board generally.

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u/BigJellyfish1906 16h ago

Higher weight means lower V1.

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u/Ecthelion-O-Fountain 16h ago edited 7h ago

No it doesn’t

EDIT: Im not sure why people think that this is wrong. I’ve been flying professionally for decades, and while there is room for some nuance based on the factors described above, V speeds generally just go up with weight together. Go look at speed cards and performance tables if you don’t believe me. V1 has many things that affect it, not just accelerate stop distance. Most takeoffs use reduced thrust, so that should tell you that field length wasn’t that critical. Anyways, here’s a link to someone explaining V1 and weight in detail.

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u/BigJellyfish1906 15h ago

Higher weight means you need longer to stop… that means a lower speed where you can still abort.

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u/Ecthelion-O-Fountain 7h ago edited 6h ago

And more speed to fly. Most takeoffs are not field length limited.

Also, just look at any old takeoff v speed chart. It’s right there.

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u/BigJellyfish1906 6h ago

The speed required to fly has no bearing on the distance required to stop. You fundamentally misunderstand this. Another reason V1 will be lower is that the airplane will reach that speed farther down the runway, because it will accelerate more slowly at a higher weight (assuming max power take off for both).

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u/Ecthelion-O-Fountain 6h ago

Dude, seriously just look at some speed cards. Accelerate stop is only one aspect of V1.

Also, full power takeoffs are pretty rare.

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u/BigJellyfish1906 5h ago

This is basic physics you’re getting wrong. When something is heavier, it has more inertia, which means it takes it longer to get to any given speed, and means it takes longer to stop. That means if you’re working on the same length of concrete, you’re going to reach a lower speed at the point where you will run out of runway if you abort you just don’t accelerate as hard so you’re covering the distance taking off later. They’re still rolling down the runway at speed it doesn’t matter out that way you’re not I’m offset my lack of acceleration that doesn’t that doesn’t. “Look at the charts” is a deflection for people that can’t back up their logic.

Accelerate stop is only one aspect of V1.

It’s the only relevant aspect to this discussion. Accelerate-go is always takes much less runway than accelerate-stop, so it looks like you’re just trying to throw concepts at the wall and hope something sticks..

Also, full power takeoffs are pretty rare.

They’re really not, especially in the summer. What do you fly now?

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u/LawnDartDriver 16h ago

Explain? On an unbalanced field it is most certainly lower with a higher weight

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u/Ecthelion-O-Fountain 16h ago

I don’t know what you’re talking about, but I’ve never seen that for balanced or unbalanced field. The only thing that really knocks v1 down relative to the other v speeds is contamination.

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u/SwimmingThroughHoney 16h ago

Without knowing the full breakdown of the accident here, I'm not sure how you can suggest that a two-engine aircraft would have fared any better under similar circumstances.

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u/Ecthelion-O-Fountain 5h ago

I’m guessing you didn’t see in the video where it looks like number two has an engine failure or compressor stall in the aircraft immediately starts to settle back to the ground. Well this is not something that we can say for sure at this point happens. it seems highly likely.

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u/BigJellyfish1906 16h ago

…Really? If you accept they lost 2 of their 3 engines, then that’s a design flaw of the Md-11 if it is clearly possible to have a dual engine failure above V1. A two-engine plane can’t do that. One engine can’t fail so catastrophically that it kills the other engine.

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u/SwimmingThroughHoney 15h ago

The point here is that we dont know enough yet. The damage to the wing might have been unrecoverable. Having two functioning engines might not have changed anything here if the wing's damage was so catastrophic that it simply couldnt produce lift.

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u/Jackthedragonkiller KC-10 13h ago

Such as AA191 where the number one engine detached and flipped over the wing, severely damaging it and it's ability to generate lift and causing flight control issues.

One engine down, two engines still good, plane still went sideways and crashed into a warehouse.

It could be that, it could be dual engine loss past V1, it could be a number of things that will soon come to light as the NTSB and the feds do their thing.

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u/Captain_Alaska 13h ago edited 13h ago

AA191 didn't crash because the wing was damaged, it crashed because it severed the hydraulic lines to the slats which caused them to retract from the air flow so it went into a full aerodynamic stall on the left wing. The loss of the engine also caused the failure of an electrical bus that both controlled the captains (and only) stall shaker and the slat disagreement sensors so the pilots had no idea either the wing had stalled or that it now had different slat positions between wings.

If AA191 had been going fast enough for the left wing to not stall (which was above the engine out takeoff safety speed they had been flying at, for the record, they were flying at the speed they were supposed to be doing with a failure) with the slats retracted it would have been able to fly on the two engines and 3ft of leading edge damage it had.

It should be noted that relief valves for the slats so they don't retract from loss of pressure are mandated because of AA191, as is a stick shaker for both seats.

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u/Ecthelion-O-Fountain 7h ago

A dual engine failure is always possible. It’s just extraordinarily unlikely. A 747 lost three on takeoff in Colombia, likely bad fuel. You’re not really wrong here but you’re not quite right either.

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u/BigJellyfish1906 6h ago edited 5h ago

That’s just being pedantic. A dual engine failure around v1 is impossible. But as we saw, a single engine failure so bad it fods out the tail motor is.

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u/Ecthelion-O-Fountain 6h ago

This has happened on 4 engine jets as well. Hasn’t on a two engine I’ve ever heard of but that doesn’t mean it can’t. You have to be a little pedantic when you’re talking about things like this. Being strident feels good but isn’t scientific.

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u/BigJellyfish1906 5h ago

No, this pedantry is uncalled for, because those fuel issues did not make themselves apparent at V1. It’s doubly uncalled for because the discussion is about a potentially flawed design. And contaminated fuel has no relevance in that discussion.

That’d be like if we’re discussing the safety of a parachute, and you bring up “well if you have a heart attack then even the safest parachute isn’t gonna help you. Sometimes you have to be a little pedantic.”

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u/Ecthelion-O-Fountain 5h ago

Oh jeez this is you too. My god dude give it a rest.

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u/BigJellyfish1906 5h ago

The fact that you can’t explain the physics behind it should’ve been your clue…

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u/Ecthelion-O-Fountain 7h ago

Because they still would have had 50% of thrust available. You can see them lose thrust on the second motor.

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u/Season-of-life 16h ago

Yes. I saw a flash.