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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?

#331

Post by YeGoblynQueenne »

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?

Can't speak about the OP but I didn't weigh a few thousand metric tons as a kid.

Or as an adult. I am on a diet though.

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

#333

Post by hypeatei »

MoreMoore wrote: post #164
blueflow wrote: post #77

I'll recite an avherald comment: If you look at "Video of aircraft after touchdown sliding along the runway and impacting the fence:", you will find out that it took them ~1.7 sec from leaving the tarmac until they hit the construction. If you measure the distance on Google earth you come up with ~140m. That means they hit the construction with roughly 296km/h or 160 knots. If it wasn't the construction it would have…

So you'd rather them have a certain 100% chance of death instead of more leeway and a chance against much less robust trees? Honestly, if I crash land, I think I prefer 150 more meters and a tree as the obstacle over the concrete block. What is going on here and what's with this crazy ass logic?

> What is going on here and what's with this crazy ass logic?

Nothing is crazy about it. Many people in this thread (like you) are in a tizzy over a concrete wall for a plane landing with no gear at high speeds. Your argument is basically "having no wall would make me feel better" which has no logic and very obtuse.

The ground is also a hard obstacle and this plane would've hit uneven ground shortly after the runway regardless. It's going to disintegrate either way.

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

#334

Post by ricardobeat »

JohnKemeny wrote: post #299
ricardobeat wrote: post #289

Earlier quoted context omitted.

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.

The wall is clearly not the cause of your accident, but might nevertheless be the cause of your death.

Technically correct yet missing the point. The plane could have disintegrated in a dozen other ways if the wall wasn’t there, or something else could be in the way.

I think the fact we have dramatic footage of the crash makes it a very attractive topic for engagement. News are spinning it into something it is not. A handful of massive errors happened and we know nothing yet, the focus on the structure for being in the way just makes for good clickbait, gives people an easy target to blame - the airport, engineers, regulators (doesn’t really matter who), and something to get riled up about.

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

#335

Post by [deleted] »

mda wrote: post #302
reisse wrote: post #203

Earlier quoted context omitted.

No amount of ample room will help if the plane touches down overshooting more than half of the runway. Furthermore (this is pure speculation at the moment) I think chances are the crew were kind of cosplaying PIA PK-8303 - forgot about landing gears in a stress from bird strike, attempted go-around after realising it, but had not enough power from engines due to bird strike or ground hit. It's plausible final investi…

So survival chance of hitting a concrete wall and open field would be same? I don't think so.

[deleted]

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

#336

Post by imglorp »

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.

And if you don't have the space, there's also arresting systems you can install in case an aircraft runs long.

https://en.wikipedia.org/wiki/Engineered_materials_arrestor_...

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

#337

Post by alkonaut »

m463 wrote: post #328
alkonaut wrote: post #301

Earlier quoted context omitted.

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.

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.

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

#338

Post by cratermoon »

bombcar wrote: post #143
ptsneves wrote: post #100

Earlier quoted context omitted.

Don’t know why you are downvoted. I was even taught that if after reporting an emergency you are overwhelmed by information requests you should just mute the radio and focus on solving the emergency . ATCs job is to get everybody out of the way including themselves.

ATC can cause crashes by vectoring planes at the same altitude. But the tower at an airport, their job is to supply information, and once you call mayday you’re in total control - you can ask them to do whatever you think will help you save the flight, including (and usually automatically done) diverting all other flights, clearing all runways, and cancelling any departures pending until the issue is resolved. Pilots…

Arguably, ATC trying to override the decisions of the pilot caused this crash at Houston Hobby Airport in 2016: https://www.flyingmag.com/aftermath-cirrus-crash-june-2016/

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

#339

Post by loeg »

xigency wrote: post #316
loeg wrote: post #171

Earlier quoted context omitted.

I've seen reports they had gear down in the first approach and also that they didn't. Is there anything conclusive yet?

Yes, if you view the footage of the bird strike on first approach you will see the landing gear is extended. ETA: The primary footage is hard to find now that the topic is so saturated, but there is a specific clip from a close vantage where it is highly visible. I'll include a link if I can find it.

8ish seconds into https://x.com/sentdefender/status/1873185457288429583 , it looks like the gear is already up.

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

#340

Post by WalterBright »

fontrash wrote: post #284
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?

Trying to get the conspiracy theories started early, eh? I would say I expect better from you, Walter, but at this point, I really don't.

I brought this point up online over 20 years ago. The pushback I got was it was too expensive to set up such cameras. I countered with if a 7-11 could install a security camera that recorded on VHS tapes, a couple cameras could be mounted in the control tower pointed at the runway. I still got a lot of pushback.

Frankly, I'm baffled.

So why do you think such cameras don't exist?

P.S. Back then, as well as today, I'm surprised at the level of pushback on this question, but no answers.

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