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UPS plane crashes near Louisville airport

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Re: UPS plane crashes near Louisville airport

#141

Post by anal_reactor »

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).

Trust is hard to earn and easy to lose. It'll take a while before we look at American planes through lenses other than Boeing straight-up lying.

Re: UPS plane crashes near Louisville airport

#142

Post by hypercube33 »

bombcar wrote: post #132
jacquesm wrote: post #85

Earlier quoted context omitted.

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.

There has been at least one crash due to manufacturing defects that no one knew about beforehand or could therefore diagnose. We will find out what happened in about a year once the investigation is complete.

Re: UPS plane crashes near Louisville airport

#143

Post by [deleted] »

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…

[deleted]

Re: UPS plane crashes near Louisville airport

#144

Post by jacquesm »

bombcar wrote: post #132
jacquesm wrote: post #85

Earlier quoted context omitted.

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.

You may well be right. Or... maybe there was a non-stress related manufacturing issue with a turbine blade. Maybe it ingested a bird, maybe it sucked in some crap lying on the runway. Maybe there as an issue with a part that was replaced during the 2 hour service just prior to the flight. Maybe there was an error during that service, or a defect that was overlooked. And a million other possibilities.

Re: UPS plane crashes near Louisville airport

#145

Post by hugh-avherald »

panxyh wrote: post #78
FabHK wrote: post #68

Earlier quoted context omitted.

V1 is the speed at which you can still stop the plane before the end of the runway. (It is computed for each takeoff based on runway length, aircraft mass, takeoff engine power setting, flaps, wind, runway condition, etc.) When the plane reaches V1, pilots take the hand off the throttle: they're committed to takeoff, even if an engine fails. It is better to take off and fix the problem or land again, than to smash in…

Isn't there any margin? Does it calculate stopping before end of runway or before causing damage? Surely uncertainty about the situation contributes to defaulting to committing, but what if it's a passenger plane and at V1 pilots know they've lost power? Wouldn't veering into highway at 30 mph be weighted against certain, big loss of life? Edit: I now see that this has been partially answered by uncle comment

V1 is the decision speed with respect to a single engine failure in a multi-engine aircraft. It's the speed below rotation speed at which the decision to abort safely can no longer be made.

Captains can make the decision to abort the takeoff in the case of absolute power loss or for 'failure to fly' (where the aircraft is clearly not going to fly, e.g. the elevator/pitch controls aren't responding). But the training is adamant: if you're uncertain what has happened after V1 you try to fly the plane away from the runway.

Re: UPS plane crashes near Louisville airport

#146

Post by justin66 »

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…

> Louisville is now a firestorm as a result.

Let's leave that word to mean what it actually means. Louisville experienced a serious fire.

Re: UPS plane crashes near Louisville airport

#147

Post by amelius »

linehedonist wrote: post #82
FabHK wrote: post #65

Earlier quoted context omitted.

> Do runways have some sort of barrier between them and the next "important" thing. It seems like that would be prudent both for cases like this Ha, Jeju Air Flight 2216 smashed into a barrier on the second landing attempt in Muan last year [0], and people commented "How could there be a barrier at the end of the runway, so obviously stupid, irresponsible", etc. Now a plane does not smash into a barrier at the end of…

One improvement is a bed of concrete at the end of the runway that will catch the wheels and slow an airplane down to a stop. Pretty much everyone agrees it’s a good idea but it’s not always possible due to space needs or cost. https://en.wikipedia.org/wiki/Engineered_materials_arrestor_...

Also put the fire department right next to it. Or some kind of automated extinguisher.

Re: UPS plane crashes near Louisville airport

#148

Post by Modified3019 »

bombcar wrote: post #131
HPsquared wrote: post #124

Earlier quoted context omitted.

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).

The aircraft hit the roof of a UPS warehouse, barely clearing it before coming down in the parking lot/junkyard nearby. So when we see it turning over in its last seconds (like the trucker dash cam video), it only had one wing at that point.

Re: UPS plane crashes near Louisville airport

#149

Post by krisoft »

positron26 wrote: post #55
Jtsummers wrote: post #20

Earlier quoted context omitted.

> The crew wouldn't have had any way to know that one of their engines had not simply failed, but was straight-up gone with their wing on fire to boot. I don't know about the MD-11 itself, but other aircraft from that time period have sensors to detect and report overheat and fire in various parts of the aircraft, including engines and wings.

This puts an impractical amount of faith in the sensor wiring when the whole pylon and cowling are shredded.

It is a very practical amount of fait.

There are two fire detection loops for each engine.[1] Even if both fails (because they get shredded as you say it) the system will report an engine fire if the two loops fail within 5s of each other. (Or FIRE DET (1,2,3,or APU) FAIL, if they got shredded with more than 5s in between without any fire indications in between.)

The detection logic is implemented directly below the cockpit. So that unlikely to have shredded at the same time. But even if the detection logic would have died that would also result in a fire alarm. (as we learned from the March 31, 2002 Charlotte incident.)[2]

In other words it is a very reliable system.

1: page 393 https://randomflightdatabase.fr/Documents/Manuel%20Aviation/...

2: https://www.fss.aero/accident-reports/dvdfiles/US/2002-03-31...

Re: UPS plane crashes near Louisville airport

#150

Post by wongarsu »

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…

It'd certainly need more thought put into it than just showing the camera view from the entertainment system. Either just one camera on the tail pointed forwards, so you have one single camera that can show the whole plane, or two cameras in the front, one pointed at each wing. Two cameras is worse than one, but they are less likely to be affected by smoke or blood splatters or whatever. Maybe give each pilot one of the camera feeds. And you'd have to fit a dedicated screen for the video feed so pilots don't need to switch through screens in an emergency.

It'd take lots of testing and engineering. But especially in cases where you have multiple warnings going off I imagine that a quick view at an exterior camera can often give you a clearer/faster indication of the situation

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