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UPS plane crashes near Louisville airport

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Re: UPS plane crashes near Louisville airport

#131

Post by bombcar »

HPsquared wrote: post #124
ragazzina wrote: post #120

Earlier quoted context omitted.

> There's also a very big difference between "Engine failure: something has damaged or jammed enough components that the turbines are no longer spinning fast enough to produce thrust or drive the generators" and "Engine failure: the engine is no longer attached to the aircraft, which is why it is no longer producing thrust". However, both things are reported in the cockpit as ENG FAIL. What is the difference?

Wider effects like damage to the wing or changes to aerodynamics. Edit: and damage to other engines, possibly engine #2 in the tail ingesting debris in this instance.

That's the biggest, the weight gone entirely unbalances the plane; if you knew exactly what happened you MIGHT be able to keep it level (and it seems they did for a bit) but eventually airspeed drops, it tips, and cartwheels (which is apparently what it did from the videos).

Re: UPS plane crashes near Louisville airport

#132

Post by bombcar »

jacquesm wrote: post #85
pseingatl wrote: post #64

Another DC-10/MD-11 crash. Does UPS perform their own engine maintenance, or do they outsource the work? What is the effect of the recent layoff of 40,000 and the current cost-cutting project?

Maybe wait with the judgements until the report is in? There are so many possible reasons why this could have happened that have nothing to do with the two items you listed (though it maybe that it does, it is just a bit pointless to assign blame before you know what the cause of the accident was).

I mean the engine is laying on the side of the runway and the plane is seen on fire trying to take off; I'm going to go out on a limb and say maintenance was somehow involved.

Well-maintained planes don't do that.

Re: UPS plane crashes near Louisville airport

#133

Post by lazide »

appreciatorBus wrote: post #18
andy99 wrote: post #7

Earlier quoted context omitted.

I specifically remember watching a flight test doing an aggressive takeoff and having the voiceover say that aircraft (two engine) need to have enough power to take off full with one engine. And so can take off very steeply empty with two engines. Would that not also be the case for these planes?

All planes are definitely capable of taking off safely even if they lose an engine at the worst time. Whatever happened here, I would be shocked if lack of thrust in the 2 remaining engines was a significant factor unless someone really screwed up the load calculations and they were overweight for conditions.

Single engine planes (GA, and some military planes) don’t handle this condition well at all.

In fact, for awhile (maybe still the case), the #1 killer of skydivers was single engine failure on takeoff from the jump plane (and similar aircraft failures), not accidents ‘while skydiving’.

Re: UPS plane crashes near Louisville airport

#134

Post by trallnag »

octaane wrote: post #27

This is probably the worst way a plane could go down in terms of damage caused. Maximum effect in term of damage. Cargo plane apparently reached V1 (go/no go speed) on the runway, and suffered a catastrophic engine failure. They passed V1, so they knew they were going down. Engine was shedding large debris, including the housing (!!!) which is a shrapnel shield. They were on fire just as they reached V1. Plane was fu…

Makes me think of the song "огромное небо" https://youtu.be/0EQNv8L49cs?si=2LTHtiKNvpZVDWVy

Work place related accidents always have a certain tragedy to them. Still remember when in the industrial park, my employer is located in, tanks belonging to a trash incinerator for special chemical waste exploded, taking several people with it.

Re: UPS plane crashes near Louisville airport

#135

Post by actionfromafar »

rob74 wrote: post #127
mrb wrote: post #125

Earlier quoted context omitted.

Oh woah, very insightful discussion thread you found there. So the tl'dr is: the leading very preliminary theory is that the MD-11's left engine fell off the wing just like https://en.wikipedia.org/wiki/American_Airlines_Flight_191 (a DC-10, the immediate predecessor of the MD-11) which was caused by maintenance errors weakening the pylon structure holding the engine.

This video from an aviation youtuber contains a picture of the engine: https://www.youtube.com/watch?v=U4q2ORhIQQc&t=526s (the video itself is also worth watching in full IMHO). What strikes me as odd is that this looks like the "naked" engine, without the cowling/nacelle that usually surrounds it? Anyway, if an engine departs the aircraft shortly after (last-minute) maintenance was performed on it, that's indeed sus…

The cowling was probably easily torn off when the engine went full speed like a missile for a few seconds after detaching.

Re: UPS plane crashes near Louisville airport

#136

Post by TheOtherHobbes »

bathtub365 wrote: post #88
appreciatorBus wrote: post #76

Earlier quoted context omitted.

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…

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…

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.

Re: UPS plane crashes near Louisville airport

#137

Post by krisoft »

ExoticPearTree wrote: post #113
roryirvine wrote: post #102

Earlier quoted context omitted.

During engine failure / fire situations, I would expect that pilots are likely to be too busy to have any time left over for peering at a video feed, trying to assess the state of the wing. In emergencies, information overload tends to make things worse, not better.

Having cameras pointed at the engines/wings like rearview mirrors would be helpful. It does not add that much workload if you take a quick glance in the “mirror” and figure out what the problem exactly is. And now we have technology that allows for cameras everywhere to give a better situational awareness across all critical aircraft surfaces and systems. It is going to take a little bit of adjusting to, but it will…

> Having cameras pointed at the engines/wings like rearview mirrors would be helpful.

Helpful in what way? What are the pilots going to do with the information?

Re: UPS plane crashes near Louisville airport

#138

Post by ceejayoz »

skim_milk wrote: post #111
pseingatl wrote: post #64

Another DC-10/MD-11 crash. Does UPS perform their own engine maintenance, or do they outsource the work? What is the effect of the recent layoff of 40,000 and the current cost-cutting project?

The last MD-11 crash with deaths was in 2009 and the last DC-10 kerfuffle was when their unapproved replacement parts fell on the runway and killed the Concorde. I wonder if flight 232 gave them a bad name - everybody seems to know that accident. Looks like have a good record otherwise.

The DC-10 had some significant design flaws at the start.

Re: UPS plane crashes near Louisville airport

#139

Post by ExoticPearTree »

cedilla wrote: post #115
ExoticPearTree wrote: post #113

Earlier quoted context omitted.

Having cameras pointed at the engines/wings like rearview mirrors would be helpful. It does not add that much workload if you take a quick glance in the “mirror” and figure out what the problem exactly is. And now we have technology that allows for cameras everywhere to give a better situational awareness across all critical aircraft surfaces and systems. It is going to take a little bit of adjusting to, but it will…

This would need to be tested. There's a lot going on already during normal take-offs. Now you're in a situation where the engine fire alarm is going off, probably a few other alarms, you got so many messages on your display that it only shows the most urgent one, you're taking quick glances at 50 points in the cockpit already. And how would the cameras even work? Are the pilots supposed to switch between multiple cam…

You know how the tail camera works on the new planes? Something like that, which can be far away from the wings, but get the full picture. Am I saying it's the solution for everything? No. But after you go through the memory committed items during an emergency, you can take a look outside and be like "ah, I see better what the problem is".

If we don't try to see how it goes, we won't know if it is a good idea or not.

Re: UPS plane crashes near Louisville airport

#140

Post by ExoticPearTree »

krisoft wrote: post #137
ExoticPearTree wrote: post #113

Earlier quoted context omitted.

Having cameras pointed at the engines/wings like rearview mirrors would be helpful. It does not add that much workload if you take a quick glance in the “mirror” and figure out what the problem exactly is. And now we have technology that allows for cameras everywhere to give a better situational awareness across all critical aircraft surfaces and systems. It is going to take a little bit of adjusting to, but it will…

> Having cameras pointed at the engines/wings like rearview mirrors would be helpful. Helpful in what way? What are the pilots going to do with the information?

They won't have to rely on cabin crew description of what they see over the wings or have to send one of the pilots to take a look (see UA1175).
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