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

bbc.com

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

#341

Post by WalterBright »

hyperific wrote: post #224
WalterBright wrote: post #222

Why are we seeing random videos of this from bystanders? Why are there not video cameras constantly recording the activity on the ramp and runways?

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

After all these years, have you ever wondered why zero footage of the SST that caught fire taking off have surfaced? Or even photos? That the only video of it was taken from a car on a nearby highway?

We all know the cockpit voice recorder exists and is essential for investigating a crash. I seriously doubt there are secret cameras recording the tarmac and it's all been hushed up. There are simply no cameras there.

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

#342

Post by WalterBright »

WeylandYutani wrote: post #249
WalterBright wrote: post #222

Why are we seeing random videos of this from bystanders? Why are there not video cameras constantly recording the activity on the ramp and runways?

Because bystanders are allowed to upload their videos while companies are not. Or is it normal for security camera footage to show up on the internet where you live?

It's normal for the cockpit voice recorder to exist and be a front and center part of a crash investigation. It is for this crash, too. There's no mention of any tarmac camera recording.

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

#343

Post by LtWorf »

lolc wrote: post #326
LtWorf wrote: post #308

Earlier quoted context omitted.

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!

Even if they lock completely, they'll skid more than the entire hull's skidding no?

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

#344

Post by lolc »

LtWorf wrote: post #343
lolc wrote: post #326

Earlier quoted context omitted.

Snarky and ignorant, the two often come together. Because you seem unaware: Airplane wheels have very powerful brakes!

Even if they lock completely, they'll skid more than the entire hull's skidding no?

The trick is not to lock and use static friction. https://en.m.wikipedia.org/wiki/Stiction

Hm, the stiction page on Wikipedia does not explain how it relates to braking. Maybe check out https://en.m.wikipedia.org/wiki/Threshold_braking

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

#345

Post by __m »

ricardobeat wrote: post #305
nialv7 wrote: post #290

Earlier quoted context omitted.

bad analogy. a better one would be: a wheel fell of an F1 car, car hit perimeter wall, driver dies. should we maybe put a crash barrier in front of the wall?

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).…

Not at all. Highest standard would have been a engineered materials arresting system, which the airport didn’t have.

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

#346

Post by mmooss »

3ple_alpha wrote: post #293
dgfitz wrote: post #132

Earlier quoted context omitted.

I have been under the distinct impression for a long time that a plane slowing on the runway has very little to do with landing gear brakes.

If one divides weight of the airplane by the number of wheels it has, one would find one wheel carries around 10 times more weight than that of a truck. You even get a slightly better deal on landing when you don't have as much fuel. That's a lot of weight but nothing crazy, so on a dry runway wheel brakes alone are more than enough to stop normally. They would also wear out a lot, overheat and occasionally ignite if…

That mass has much more velocity than a truck.

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

#347

Post by m463 »

alkonaut wrote: post #337
m463 wrote: post #328

Earlier quoted context omitted.

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

Those walls are there also on airports that do have open space beyond the runway. But they’re typically fences. Significantly cheaper and doesn’t disassemble and airliner upon impact.

sorry, I guess I'm doing chesterton's fenc..wall

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

#348

Post by kristjansson »

loeg wrote: post #177
kristjansson wrote: post #167

The graphic in the article is pretty misleading. The video of the accident shows the plane touching down with about a third of the runway left, not two thirds. All discussion of the localizer obstruction is secondary to (a) why did they touch so late and (b) why did they land so urgently.

The figure I've seen is landing 1200m into a 2800m runway, which is about 1/3.

In the longer video, there's clear sparks from the tail strike when the plane is in line with the northeast-most structure of the airport. Lining that up with the camera location shows almost exactly 1200m of runway _remaining_.

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

#349

Post by Aloisius »

guiriduro wrote: post #274
Aloisius wrote: post #271

Earlier quoted context omitted.

Landings/takeoffs from 23/24R/24L are in the westerly direction (away from 427) due to prevailing winds.

But in an emergency is it impossible for aircraft to land in the opposite direction? That's what happened at Muan; the concrete structure was only present if the plane landed against the normal approach.

Impossible? No, but the fact that planes generally don't approach from that direction and there are other, longer runways to land means substantially reduce the risk of an already extremely rare event.

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

#350

Post by WalterBright »

arcbyte wrote: post #323
alex989 wrote: post #276

Earlier quoted context omitted.

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.

Wouldn't that apply to any initial evidence?
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