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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?

#61

Post by Towaway69 »

ra wrote: post #23
Towaway69 wrote: post #12

Earlier quoted context omitted.

This: > no idea he had to make the approach in the opposite direction. So the wall is actually at the beginning of the runway. That wall was never never meant to be at the end of a landing but at the start of landing. I don't understand why this isn't made clear. Basically the runway was used against the design specifications.

That's not correct. A runway can be used in either direction, if you look on Google maps you can see the runway at Jeju has markings at both ends including a number (denoting it's compass heading) - both ends are usable. You always want to land with a headwind and never a tailwind, so ATC will use whichever end is favorable for the current conditions. In this case, if they attempted to land with a tailwind then the o…

Thanks for the clarification :+1:

It should perhaps be pointed in news coverage since I equated "opposite direction" with "wrong direction" - hence my scepticisms about the wall.

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

#62

Post by lutusp »

Towaway69 wrote: post #12
mcflubbins wrote: post #3

I was wondering the same thing and suspected it was some safety feature (better for a plane to smack into said wall instead of crash into some populated area, etc) I had no idea he had to make the approach in the opposite direction.

This: > no idea he had to make the approach in the opposite direction. So the wall is actually at the beginning of the runway. That wall was never never meant to be at the end of a landing but at the start of landing. I don't understand why this isn't made clear. Basically the runway was used against the design specifications.

> So the wall is actually at the beginning of the runway. That wall was never never meant to be at the end of a landing but at the start of landing.

Airports like this are designed to have two approach directions -- in this case, 10 and 190 degrees. Either approach direction would have been acceptable depending on the prevailing wind.

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

#63

Post by notimetorelax »

dredmorbius wrote: post #49
notimetorelax wrote: post #22

Earlier quoted context omitted.

Runways are approached from both ends depending on the wind.

This depends strongly on the airport, terrain, and variability of winds. There are airports in which approaches always or very nearly always follow the same profiles given local conditions. SFO, SJC, and SAN would be three examples off the top of my head. SFO's major approaches are over the bay, opposite approaches would involve rapid descents dictated by mountains near the airport. SJO and SAN are both limited by pr…

You’re right. Looking at the charts, it appears that both 01 and 19 can be used - https://aim.koca.go.kr/eaipPub/Package/2020-07-30/html/eAIP/...

What’s noteworthy, there’s a note to use extreme caution due to this wall if landing or taking off towards it.

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

#64

Post by thekevan »

gazchop wrote: post #58
thekevan wrote: post #52

Earlier quoted context omitted.

But don't forget, that point you mention is the point where the people were killed.

There is a whole chain of causality. They were killed by multiple successive problems compounding. See Swiss cheese model.

I'm really not sure the chain of bird strike, belly landing, mid runway landing and fiery explosion are equal parts of that chain. One seems to weigh heavier than the rest.

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

#65

Post by gazchop »

thekevan wrote: post #64
gazchop wrote: post #58

Earlier quoted context omitted.

There is a whole chain of causality. They were killed by multiple successive problems compounding. See Swiss cheese model.

I'm really not sure the chain of bird strike, belly landing, mid runway landing and fiery explosion are equal parts of that chain. One seems to weigh heavier than the rest.

There's a few more you're missing there which is the point of the investigation.

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

#68

Post by rich_sasha »

ra wrote: post #23
Towaway69 wrote: post #12

Earlier quoted context omitted.

This: > no idea he had to make the approach in the opposite direction. So the wall is actually at the beginning of the runway. That wall was never never meant to be at the end of a landing but at the start of landing. I don't understand why this isn't made clear. Basically the runway was used against the design specifications.

That's not correct. A runway can be used in either direction, if you look on Google maps you can see the runway at Jeju has markings at both ends including a number (denoting it's compass heading) - both ends are usable. You always want to land with a headwind and never a tailwind, so ATC will use whichever end is favorable for the current conditions. In this case, if they attempted to land with a tailwind then the o…

I read that the opposite direction had a NOTAM exclusion, i.e. was excluded from use. From the professional pilot forum linked a few days ago in a similar thread.

If that's right then OP would be correct in saying, this direction wasn't meant to be used.

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

#69

Post by rich_sasha »

thekevan wrote: post #20
gazchop wrote: post #7

I think this is disingenuous reporting. It’s too early to actually draw a conclusion. We should wait for the full investigation. There are a large number of compounding problems here. That was just the last one.

"... the significance of the concrete wall's location about 250m (820ft) off the end of the runway." "...the runway design "absolutely (did) not" meet industry best practices, which preclude any hard structure within at least 300m (984ft) of the end of the runway." "it emerged that remarks in Muan International Airport's operating manual, uploaded early in 2024, said the concrete embankment was too close to the end o…

So it would appear that this structure would be fully compliant if placed 50m further. That's less than a second's difference. The plane would crash into it at the same speed, just a tiny bit later.

OP is 100% right that many, many things must have gone wrong for the position of this structure to remotely matter (human or mechanical errors).

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