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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?

#141

Post by bombcar »

TylerE wrote: post #107
loeg wrote: post #80

Earlier quoted context omitted.

Maybe. But maybe another 1000m of dirt would have been enough to slow them before the treeline. The area south of the runway is mostly an easement for the ILS approach equipment, then a parking lot and finally some trees. It's also definitely the case that the cement-reinforced dirt mound is not best practice for a locator array.

Yes, but in basically every single circumstance if you have room for 1000m of dirt, you have room for another 1000m of runway, which is even safer.

This is the reality - most airports run their runways “to the fence” for some variation of “to the fence”. If they could reasonably have a thousand extra feet of runway they’ll add that, as it supports more operations and doesn’t really hurt.

Some of them even move around the recommended touchdown point depending on other factors, if the runway is extra long.

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

#142

Post by bombcar »

neom wrote: post #99

My wife is South Korean (from andong). I asked her and she looked at me like I'd grown a second head "because it's South Korea? We're a young country and that is tiny airport in the south, half of Korea is a safety hazard and you know that fine well, some freaking idiot put a wall there, oh well, it's korea" and walked off pretty angry I'd even asked.

To be fair to her, check out some of the other things that have happened.

Compared to that mall collapse, a berm that far off the end of the runway won’t even be notable.

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

#143

Post by bombcar »

ptsneves wrote: post #100
K0balt wrote: post #46

Earlier quoted context omitted.

lol. People often have an idea that ATC actually controls what happens. They just give advisory guidance to pilots, who ultimately decide what to do. A clearance to land or the lack of one does not absolve the pilots from making their own judgments and decisions about how to conduct the navigation of the aircraft, and where and when to land. Usually, it’s a bad idea to not follow ATC guidance, but in the case of emer…

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 have to be trained to ignore ATC as necessary, because planes have crashed because of trying to be polite to requests (and not declaring mayday or pan pan).

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

#144

Post by 05 »

sio8ohPi wrote: post #140
hu3 wrote: post #137

Earlier quoted context omitted.

160 knots? Google tells me: "Modern jets land between 120–150 kt. This depends on weight, weather conditions and several other factors." So even after scratching asphalt for 2/3 of the runway it was still faster than the normal landing speed. My uneducated gut feeling says pilot was trying to abort the landing.

Normally they land with flaps down, which reduces landing speed.

I've heard sometimes landing gear is also involved..

We really need a placebo controlled double blind study to learn if landing gear is actually effective of just a cargo cult like parachutes.. [0] https://www.bmj.com/content/363/bmj.k5094

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

#145

Post by mikestew »

dralley wrote: post #114
iso8859-1 wrote: post #105

Earlier quoted context omitted.

[flagged]

>Tell her she is wrong. It's an international airport with commercial traffic. 11th most busiest airport in the country.[0] 11th out of 15 total, servicing about 4 flights / 630 passengers per day on average using the very same statistics you've linked. That sounds like a pretty small airport to me, both in absolute and relative terms. "International airport" means very little outside of large nations like the US, Ru…

"International airport" means very little outside of large nations like the US, Russia, Canada, Brazil or China.

In the U. S., at least, "international" just means there's a customs station. There are some pretty small airports that have "international" in the name. Fairbanks, Alaska, comes to mind.

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

#146

Post by ynniv »

bink wrote: post #126
ynniv wrote: post #108

Earlier quoted context omitted.

Cause of death was landing halfway down a runway at high speed with no gear. Why were they cleared to land if they hadn't set flaps and locked gear? There was ocean in front of them both before and after their turn: landing there would have been more survivable than landing fast and hard with no gear. They were below minimum turnback altitude, and wouldn't have been able to complete the planned turn without the same…

They declared an emergency. It's typical in that scenario to be approved for whatever runway the pilot deems best... or golf course... or field.

According to the timeline I saw they were cleared before declaring an emergency. This means at the time of emergency the standard checklist required their gear had been locked and flaps set. Either they were not operating within regulation before they declared emergency, or they raised gear and retracted flaps below 900 AGL and decided to make an impossible turn instead of stabilizing their flight.

I don't know what happened in this event, but the concrete box is painfully uninteresting compared to basically anything that happened before it.

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

#147

Post by bombcar »

rich_sasha wrote: post #68
ra wrote: post #23

Earlier quoted context omitted.

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.

Depends on why it was NOTAM’d - could be that the localizer was out, that there was a noise abatement, or other reasons.

Part of preflight is investigating those so you know what are options at what are not - entirely closed runways will be indicated if they’re actually broken up or just marked closed.

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

#148

Post by sho_hn »

iso8859-1 wrote: post #129
pfannkuchen wrote: post #113

Earlier quoted context omitted.

Were those obstacles installed by the airport though? I thought it was like stuff on land outside of the airport for those other examples.

The localizer antenna mount (the concrete) was inside the airport perimeter. See diagram: https://multimedia.scmp.com/embeds/2024/world/skorea-crash/i...

The OP knows this already.

What they were saying is that just because other airports feature runways situated next to natural obstacles and this is allowed and equally dangerous, it doesn't mean this airport needed to have this particular, deliberately designed and implemented obstacle next to the runway.

The reason for the concrete-reinforced berm was typhoon resilience. It begs the question whether there are alternative designs that are trade of requirements better.

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

#149

Post by reso »

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.

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

#150

Post by bombcar »

DoctorOetker wrote: post #138
sio8ohPi wrote: post #127

Earlier quoted context omitted.

No. The ILS localizer was 260 meters from the threshold, not 2.1 NM (3800m).

Why would there be a warning for an "obstacle" 4km away from the end of the runway? 3800 - 2800 = 1km. Did the plane skid for 1km before crashing into the obstacle?

Almost anything that is 500m causes an obstacle notice to exist. There are tons of them and most mean nothing unless you’re flying an overweight small plane in the dark desert heat.
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