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Why was there a wall near runway at S Korea plane crash airport?

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Re: Why was there a wall near runway at S Korea plane crash airport?

#321

Post by darkhorn »

inoffensivename wrote: post #92

Lots of airports have obstacles not far from the end of the runway. Burbank, Midway, Orange County are a few that come to mind. Why did they need to land when they did? Why did they need to land so soon after the mayday call? (only 8 minutes from mayday to crash, as I understand it) Why couldn't they land on a longer runway? Why did they land so far down the runway? What forced them to land in a clean configuration?…

Nice questions. But it doesn't give them right to build a concrete obstacle for lights, when it is possible to make it without hard obstacle.

Re: Why was there a wall near runway at S Korea plane crash airport?

#322

Post by broeng »

ricardobeat wrote: post #289
tooltalk wrote: post #184

Earlier quoted context omitted.

Occam's razor: the wall is most probably the cause of the unnecessary explosion that killed 179 people. The airport built ILS, or localizer, on unnecessarily over-engineered concrete structure where there shouldn't have been any obstruction. The ILS are supposed to be built on level surface or "frangile" structure so they can be easily destroyed when there is an overrun. There are reportedly at least 4 other airports…

If the wheels drop off my car at 100km/h and I lose control and hit a wall, is the wall the cause of the accident? The barrier was 250m away from the end of the runway, the extra 50m if following regulations wouldn’t have changed the outcome. And if the wall wasn’t there, the plane would dive right into a highway anyway. That’s the point.

Maybe that section of highway could easily be cleared in time with a warning system, like when we warn for crossing trains. A wall doesn't have to be the only solution.

Re: Why was there a wall near runway at S Korea plane crash airport?

#323

Post by arcbyte »

alex989 wrote: post #276
hyperific wrote: post #224

Earlier quoted context omitted.

Maybe the footage from runway cameras was sequestered for internal review.

How does hiding videos help anyone? It's not like the footage magicaly disappears when you show it to the public and investigators can't use it. We live in the digital era, it takes like 7 clicks to share the footage to the entire world. Are pilots and engineers around the world gonna be better at preventing this type of disaster if we all make sure they never ever get to see it?

Pilots and engineers will be better at preventing this type of disastr after and only after a review has been done. Just like a trial, seeing footage earlier and in a different venue than the "review room" can color opinions inappripriately and actually hender the search for truth.

Re: Why was there a wall near runway at S Korea plane crash airport?

#324

Post by [deleted] »

wlll wrote: post #319
ricardobeat wrote: post #305

Earlier quoted context omitted.

This airport is basically already complying with the highest possible standard [1]; so in your analogy the crash barrier already exists, the equivalent argument would be for the track to have a 200m run-off area all around. It's not feasible to plan for every possible freak occurrence, an accident like this is only possible after a long list of other safety procedures have failed (as is often the case for aviation).…

Standards are the minimum, not the maximum. Planes sometimes overshoot the runway, building an unecessary wall at the end of it might comply with a standard, but that doesn't make it a good idea.

[deleted]

Re: Why was there a wall near runway at S Korea plane crash airport?

#325

Post by Dalewyn »

Xixi wrote: post #251
inoffensivename wrote: post #245

Earlier quoted context omitted.

> I'm speculating, of course People should stop doing this. Transport category airplanes are designed to suffer multiple failures and still be controllable. Why the airplane landed where it did, when it did, and how fast it did are the relevant questions.

I do not think speculations on HN are impacting the investigation in any way, shape or form, although I understand your perspective. I do hope the investigation yields results that improve air travel safety.

>I do not think speculations on HN are impacting the investigation

They are and will negatively impact the final impression of the investigation results, namely an unwarranted focus on The Wall(tm) (people here are calling it the "Murder Wall", which demonstrates my point) which helps precisely noone.

The focus should primarily be on the plane, particularly in the interests of preventing a repeat.

Re: Why was there a wall near runway at S Korea plane crash airport?

#326

Post by lolc »

LtWorf wrote: post #308
khuey wrote: post #187

Earlier quoted context omitted.

Now account for the fact that the plane had no brakes since the landing gear were not deployed ...

A hull rolls better than a wheel? Has humanity been doing vehicles wrong this entire time?

Snarky and ignorant, the two often come together.

Because you seem unaware: Airplane wheels have very powerful brakes!

Re: Why was there a wall near runway at S Korea plane crash airport?

#327

Post by cm2187 »

khuey wrote: post #190
cm2187 wrote: post #8

Earlier quoted context omitted.

Like doing what things? What I read so far is that they suspect the pilot had control issues. I don't think people who say that it's a bad idea to have a concrete wall at the end of the runway argue the plane should make its way to a nearby motorway. I think most refer to using EMAS, ie a crushable concrete floor in which the plane sinks and stops.

EMAS is designed to crush under the pressure of all of the aircraft's weight pushing down on the relatively narrow contact area of the tires. There were no tires in this case. I am unaware of an EMAS that has been designed or tested for the far more broadly distributed weight of a belly landing.

That’s a fair objection. Still you would expect the plane to sink into the grass after that.

Re: Why was there a wall near runway at S Korea plane crash airport?

#328

Post by m463 »

alkonaut wrote: post #301
reso wrote: post #149

The wall is a red herring. The plane landed halfway down the runway at high speed. Something bad is going to happen if you do that at any runway on earth. In SFO you'll end up in the bay or hit the terminal depending on the orientation. In Toronto you'll crash into a highway. Stop looking at the wall and look at the minutes before the crash.

If it’s possible in any way to keep the next few km after a runway clear, then it should be clear. Ocean is great. Empty fields are great. If you are lucky enough to have empty fields but put a concrete wall there, then that’s almost malicious. The cause of any fatality in aviation is never a single thing. It’s invariably a chain of events where removing any one thing in the chain would prevent the disaster.

The wall might critical to keeping things off the runway, like animals and people.

Re: Why was there a wall near runway at S Korea plane crash airport?

#329

Post by charlieyu1 »

reso wrote: post #149

The wall is a red herring. The plane landed halfway down the runway at high speed. Something bad is going to happen if you do that at any runway on earth. In SFO you'll end up in the bay or hit the terminal depending on the orientation. In Toronto you'll crash into a highway. Stop looking at the wall and look at the minutes before the crash.

Disagree from Hong Kong. You would probably land on sea but probably end up with single digit causalities

Re: Why was there a wall near runway at S Korea plane crash airport?

#330

Post by [deleted] »

SoftTalker wrote: post #254
dredmorbius wrote: post #215

Earlier quoted context omitted.

Physics hack: The average velocity at constant deceleration is halfway between the initial and terminal velocities. So if we know the landing speed (which should come out of the flight data recorder), we'll know the terminal velocity given the average speed (distance/time) which is determinable from the video. No doubt Jeju 2216 was moving hot, but a longer run could have bled off far more speed, and kinetic energy i…

The plane was sliding on its belly, wheels up. It wasn't slowing down very much. Ever play on a slip-n-slide as a kid?

[deleted]
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