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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?

#261

Earlier quoted context omitted.

What a lame comment. This isn't how aviation safety is managed. You expect planes to land halfway down the runway at high speed and out of control. It's an eventual certainty. > 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. Ending up in a bay or crashing into a highway would likely have resulted in far less loss of life.

And hitting the terminal would likely have resulted in far more loss of life. Are airport designers supposed to consider this as "an eventual certainty"?

Yes, but there is no terminal at the end of this runway, so it’s irrelevant. The question is, wouldn’t it be safer to design airports to avoid having large concrete structures at the end of a runway in case there is a landing problem.

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

#262

Earlier quoted context omitted.

Youtuber’s Denys Davydov (ex pilot of same plane), pet theory: bird got into the engine, pilot by mistake shut off wrong engine, due to no engine - hydraulic pump was non-functional, which resulted in landing gear problems. (also something about ground effect)

This wouldn't be the first time a pilot killed the wrong engine: "TransAsia Pilot Shut Off Wrong Engine Moments Before Crash" (2015) Taiwan aviation officials on Tuesday released a detailed report of how the pilot mistakenly shut off the plane's only working engine after the other lost power. "Wow, pulled back the wrong side throttle," the captain said shortly before crashing. https://www.buzzfeednews.com/article/jas…

This whole thread is a tire fire poor logic and critical thinking.

That said, I have seen some absolutely horrendous responses to emergencies go from kinda bad to massive destruction of property, so much so that unless one has trained for the specific emergency, the best course of action is to assess way more than you think you need. And we often have more time than we think, and we make the the right decisions, they are the right decisions because they give us more time.

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

#263
post #239

Earlier quoted context omitted.

You are making an assumption here, that I think is unreasonable: that the pilots (who have probably landed at this airport hundreds of times, it's not like they don't know the place) were expecting a large piece of reinforced concrete to be in the path of the plane. I'm speculating, of course, but pilots made the decision to land there (albeit in a very short amount of time). They probably made the reasonable assumpt…

Firstly, this airport has only been taking international flights since the early December. There was also construction work going on at one end of the runway (until March), and the threshold was pushed back 300 metres, shortening the runway by that much: http://aim.koca.go.kr/eaipPub/Package/2024-10-31-AIRAC/html/... The runway also is not flat (which is why the localiser beams at that end need to be raised in the fi…

Very good point regarding international flights.

Of course, I'm making the assumption that the pilots somehow had to attempt a "a very fast landing, with no gear or flaps, spoilers". The core of the issue is probably there, hopefully the investigation will yield useful results.

But what I am fundamentally questioning is whether the pilots would have attempted that landing if they had been expecting a piece of reinforced concrete at the end of the runway.

To say it differently, it's not the existence of deadly obstacles near an airport that bothers me (after all, some runways are quite literally in the middle of cities), but the fact that the pilots could have reasonably not know about them. That, for me, is a pretty big issue.

There were plenty of concrete structures nearby when US Airways Flight 1549 ditched into the Hudson river: notice the pilot aimed for a path where there weren't any. Maybe that Jeju air pilot could have attempted something similar. Maybe not. But the absurd nature of that deadly piece of reinforced concrete probably didn't help making a good decision.

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

#264
post #199

Earlier quoted context omitted.

Very, very few airport runways are long enough for a plane without brakes to land halfway and be fine. It's simply not possible to build airports in useful places and guarantee three-mile runways.

You don't need the aircraft to survive. You need the passengers to survive. And that's eminently possible, even where the hull itself is destroyed (several cases of fuselages splitting in two or three with no or minimal fatalities): https://news.ycombinator.com/item?id=42606790 >

The choice of keeping the craft intact is much more likely likely to lead to a safer outcome, isn't it?

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

#265

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?…

The obstacle obviously didn't cause the crash, but it's still probable that fewer people would have died if it wasn't there, and it seems to have been put there for no valid reason, quite recently, and against standard practice. Along with the reports that their bird control devices had not been implemented and that only 1 of the required 4 staff to repel birds were on duty. All these factors together may suggest an…

I don't know why the pilots landed the way they did but the structure was there for a valid reason. It's the runway localizer antenna. It was elevated off the ground to protect it from flooding. Should it have been frangible, yes, but it's not at all out of the ordinary as far as structures near runways go, and I think the focus on it is sensationalist and misguided.

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

#266
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.

[deleted]

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

#267
post #264

Earlier quoted context omitted.

You don't need the aircraft to survive. You need the passengers to survive. And that's eminently possible, even where the hull itself is destroyed (several cases of fuselages splitting in two or three with no or minimal fatalities): https://news.ycombinator.com/item?id=42606790 >

The choice of keeping the craft intact is much more likely likely to lead to a safer outcome, isn't it?

It's a vastly more challenging goal, with higher engineering, financial, and land-use requirements.

Passenger survivial: Decelleration g-forces kept within a given threshold, evacuation slides operable, passengers cleared within 90 seconds. Hull is sacrificed.

Airframe survival: No significant damage to aircraft structure or systems.

Humans in this case are substantially more robust than aircraft.

You'll find a similar situation in, e.g., earthquake safety construction. The goal isn't for structural reuse, but for inhabitant survivability. Structures may be renovated in some case but are generally demolished and replaced. They did their job in saving lives.

Steel-reinforced concrete buildings can still sustain considerable damage, possibly to the point that they will be unusable after the quake. This has to do with the way governments set building codes, which tell engineers how to design a building to withstand a certain level of earthquake shaking. Codes, including those in the U.S. and Turkey, generally require that a building achieves what is called “life safety” under a given maximum expected earthquake in an area. “Our seismic codes are only a minimum requirement,” says Sissy Nikolaou, research earthquake engineer at the National Institute of Standards and Technology. “You just want these buildings at least to give you the chance to get out of it alive when the big one happens, under the assumption that they may be seriously damaged.” The situation is akin to a car that crumples in a crash: the vehicle absorbs the impact to protect passengers, but it is totaled.

https://www.scientificamerican.com/article/how-to-engineer-b...>

The automobile-safety example given above is also apt. A car can be destroyed in a crash, what's key is that its occupants survive.

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

#268
post #203

Earlier quoted context omitted.

To continue your idiom, it's not a red herring, it's the elephant in the room. Seriously, I think the incident it's a hard lesson for airport designer and ICAO. For better civil aviation safety, the next airport runway should have ample room for safer aircraft landing without landing gears. Previously there's no real-time aircraft tracking requirement for passenger aircraft only for cargo, but after MH370 it's mandat…

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…

People keep saying "half the runway", "more than half the runway" in this thread. The linked article has a large graphic saying the plane touched down about a third of the way down the runway.

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

#269
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.

Right. Pilot boards agree on this. It's clear that the plane landed halfway down the runway at high speed, no gear, flaps, slats, or speed brakes. A runway overrun was inevitable from that point. Nobody knows yet why they landed in that configuration. Failed go-around? Engine out landing? Cut wrong engine after a bird strike? Loss of hydraulics? Too rushed for landing checklist in an emergency? All of those are possi…

> One article says the runway was equipped with EMAS, an Engineered Materials Arresting System.

> https://focustaiwan.tw/society/202412300010

Nowhere in that article says Muan Airpot has EMAS, it says a local official confirmed that Songshan Airport in Taipei has EMAS, following local concerns that Songshan Airport has an even shorter runway (2600m vs 2800m in Muan).

A thread full of armchair experts is already bad enough, please don't make it worse with seemingly well-supported misinformation.

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

#270
post #269

Earlier quoted context omitted.

Right. Pilot boards agree on this. It's clear that the plane landed halfway down the runway at high speed, no gear, flaps, slats, or speed brakes. A runway overrun was inevitable from that point. Nobody knows yet why they landed in that configuration. Failed go-around? Engine out landing? Cut wrong engine after a bird strike? Loss of hydraulics? Too rushed for landing checklist in an emergency? All of those are possi…

> One article says the runway was equipped with EMAS, an Engineered Materials Arresting System. > https://focustaiwan.tw/society/202412300010 Nowhere in that article says Muan Airpot has EMAS, it says a local official confirmed that Songshan Airport in Taipei has EMAS, following local concerns that Songshan Airport has an even shorter runway (2600m vs 2800m in Muan). A thread full of armchair experts is already bad e…

Oh, you're right. Different airport. Sorry.

Muan does have the chevron markings on the overrun area, but that does not always indicate EMAS.

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