Why was there a wall near runway at S Korea plane crash airport?(bbc.com)
bbc.com
Why was there a wall near runway at S Korea plane crash airport?
https://www.bbc.com/news/articles/c0mvynnxzzmo
364 comments
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.
Occam's razor: the wall is most probably the cause of the unnecessary explosion that killed 179 people. The airport built ILS, or localizer, on unnecessarily over-engineered concrete structure where there shouldn't have been any obstruction. The ILS are supposed to be built on level surface or "frangile" structure so they can be easily destroyed when there is an overrun. There are reportedly at least 4 other airports with such obstructions in South Korea -- at Yeosu, it's 4 meters high (also concrete foundation)[1].
<strikethrough>There was a similar accident in Hiroshima, Japan several years ago: Airbus A320-200 skidded past the end of the runway at similar speed and struck down ILS. It eventually stopped -- damaged the airplane but no fatality.</strikethrough>
1. Localizer at Yeosu Airport, similar to Muan's, raises safety concerns, 2025.01.02 (23:58), KBS News.
<strikethrough>There was a similar accident in Hiroshima, Japan several years ago: Airbus A320-200 skidded past the end of the runway at similar speed and struck down ILS. It eventually stopped -- damaged the airplane but no fatality.</strikethrough>
1. Localizer at Yeosu Airport, similar to Muan's, raises safety concerns, 2025.01.02 (23:58), KBS News.
> There was a similar accident in Hiroshima, Japan several years ago: Airbus A320-200 skidded past the end of the runway at similar speed and struck down ILS. It eventually stopped -- damaged the airplane but no fatality.
Are you talking about Asiana Airlines 162? It hit localizer on its way to the runway because it came in too low. It then hit the runway, skidded on the runway, and stopped about halfway (after veering off the runway at the last moment).
If the same thing happened in Muan, the plane would have hit the localizer and then touched down, stopping in the runway. The fact that the localizer's base was concrete wouldn't have mattered because that's not where the plane would hit it.
Are you talking about Asiana Airlines 162? It hit localizer on its way to the runway because it came in too low. It then hit the runway, skidded on the runway, and stopped about halfway (after veering off the runway at the last moment).
If the same thing happened in Muan, the plane would have hit the localizer and then touched down, stopping in the runway. The fact that the localizer's base was concrete wouldn't have mattered because that's not where the plane would hit it.
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 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.
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.
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).
[1] https://en.wikipedia.org/wiki/Runway_safety_area
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).
[1] https://en.wikipedia.org/wiki/Runway_safety_area
Standards are the minimum, not the maximum.
Planes sometimes overshoot the runway, building an unecessary wall at the end of it might comply with a standard, but that doesn't make it a good idea.
Planes sometimes overshoot the runway, building an unecessary wall at the end of it might comply with a standard, but that doesn't make it a good idea.
[deleted]
Not at all. Highest standard would have been a engineered materials arresting system, which the airport didn’t have.
Maybe that section of highway could easily be cleared in time with a warning system, like when we warn for crossing trains. A wall doesn't have to be the only solution.
I suppose we have to get into the engineering thought process of these Asian cultures.
Where did the idea of fortifying Localizer (LOC) come from, was there prior art specifying any degree of fortification (or lack) ? Perhaps these kind of radar (adjacent) installations are traditionally fortified, like maybe the civil air services were influenced from militry air services were things tend to be overengineered?
Perhaps saving the LOC is more important than saving a single aircraft? Some idea like this piece of infrastructure being more important that any single aircraft's safety?
The point is we might not see the reason why fortifying the LOC was obvious or straight forward to the Korean engineers.
Also, I've seen no credible evidence to support the idea the LOC is supposed to be built on a level surface, or built in a destructable way. Addressing the first point, the LOC makes sense to be slightly elevated given how they operate with near field low power radio waves. That said, these kind of slightly elevated instrument might not require an earthen mound, sourounded by concreate walls. Which goes to the second point, I can think of reasons to have these kind of LOC runways homing antenas destructable, and I can see them being robustly durrable. This thing was way past the end of the runway, and as unpo0pular as it might seems... it's a very bad thing to run out of runway. Somebody else wrote that some airports have a lack of open field beyond the end of the runway, and so it's a persuasive argument stuff could be built out there.
Where did the idea of fortifying Localizer (LOC) come from, was there prior art specifying any degree of fortification (or lack) ? Perhaps these kind of radar (adjacent) installations are traditionally fortified, like maybe the civil air services were influenced from militry air services were things tend to be overengineered?
Perhaps saving the LOC is more important than saving a single aircraft? Some idea like this piece of infrastructure being more important that any single aircraft's safety?
The point is we might not see the reason why fortifying the LOC was obvious or straight forward to the Korean engineers.
Also, I've seen no credible evidence to support the idea the LOC is supposed to be built on a level surface, or built in a destructable way. Addressing the first point, the LOC makes sense to be slightly elevated given how they operate with near field low power radio waves. That said, these kind of slightly elevated instrument might not require an earthen mound, sourounded by concreate walls. Which goes to the second point, I can think of reasons to have these kind of LOC runways homing antenas destructable, and I can see them being robustly durrable. This thing was way past the end of the runway, and as unpo0pular as it might seems... it's a very bad thing to run out of runway. Somebody else wrote that some airports have a lack of open field beyond the end of the runway, and so it's a persuasive argument stuff could be built out there.
You might find AA 1420 (1999) of interest, similar situation though far fewer fatalities (11 of 145 souls):
<https://en.wikipedia.org/wiki/American_Airlines_Flight_1420>
Partially-effective runway braking and a much greater distance from runway perimeter to the nonfrangible ILS structure likely played a role.
<https://en.wikipedia.org/wiki/American_Airlines_Flight_1420>
Partially-effective runway braking and a much greater distance from runway perimeter to the nonfrangible ILS structure likely played a role.
Are you talking about Asiana 162? https://en.m.wikipedia.org/wiki/Asiana_Airlines_Flight_162
That one touched down short of the runway at a much lower speed and configured for landing.
That one touched down short of the runway at a much lower speed and configured for landing.
> The ILS are supposed to be built on level surface or "frangile" structure
Nit: I think the word you want is “frangible”, easy to break.
Nit: I think the word you want is “frangible”, easy to break.
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 assumption that they could "safely" (as safe as it can be, of course) overshoot the runway in that direction. They were certainly not expecting to hit a concrete structure that would pulverize their plane.
Having large concrete structures near airports is not unreasonable, hiding them absolutely is. If instead of a hidden piece of concrete it had been a terminal like in SFO, a sea wall, or another known hazardous structure, the pilots could very well have decided to land somewhere else. Including in the very large body of water next to (or beyond) the runway.
You don't know, I don't know, and we might never know depending on what is uncovered by the investigation.
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 assumption that they could "safely" (as safe as it can be, of course) overshoot the runway in that direction. They were certainly not expecting to hit a concrete structure that would pulverize their plane.
Having large concrete structures near airports is not unreasonable, hiding them absolutely is. If instead of a hidden piece of concrete it had been a terminal like in SFO, a sea wall, or another known hazardous structure, the pilots could very well have decided to land somewhere else. Including in the very large body of water next to (or beyond) the runway.
You don't know, I don't know, and we might never know depending on what is uncovered by the investigation.
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 first place to intercept the correct glideslope angle).
As the OP mentioned, trying this (a very fast landing, with no gear or flaps, spoilers) at many airports around the world on such a short runway (albeit one which with gear and flaps down is long enough for normal landings with the required 240 m runoff areas), is not going to work well.
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 first place to intercept the correct glideslope angle).
As the OP mentioned, trying this (a very fast landing, with no gear or flaps, spoilers) at many airports around the world on such a short runway (albeit one which with gear and flaps down is long enough for normal landings with the required 240 m runoff areas), is not going to work well.
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.
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.
In most airports you can expect highways, buildings, water and other structures after the runoff area.
The airport where it happened doesn’t appear to have any less clearance than usual around the runway [1], if not more when comparing to Jeju Airport for example [2].
[1] https://maps.apple.com/?ll=34.976342,126.382712&q=Marked%20L...
[2] https://maps.apple.com/?ll=33.515456,126.498733&q=Marked%20L...
The airport where it happened doesn’t appear to have any less clearance than usual around the runway [1], if not more when comparing to Jeju Airport for example [2].
[1] https://maps.apple.com/?ll=34.976342,126.382712&q=Marked%20L...
[2] https://maps.apple.com/?ll=33.515456,126.498733&q=Marked%20L...
You're making an assumption that the outcome would have been different if that wall wasn't there. You're wrong. 50m past that wall is another wall, 5m after that is a highway.
Indeed I'm making tons of assumptions, but you have not yet convinced me that they are wrong. A brick wall is no reinforced concrete, and how is a road at plane level fundamentally different from the runway the plane was "gliding" on?
the 2nd wall is a brick wall, rather than reinforced concrete (which is what seems to be the first wall).
I dont think the plane would get pulverized hitting a brick wall, and the distance will also slow the speed.
And the highway is not above the plane's travel axis, so the highway is a non sequitur. Not to mention even more distance to slow down.
I dont think the plane would get pulverized hitting a brick wall, and the distance will also slow the speed.
And the highway is not above the plane's travel axis, so the highway is a non sequitur. Not to mention even more distance to slow down.
[deleted]
> I'm speculating, of course
People should stop doing this. Transport category airplanes are designed to suffer multiple failures and still be controllable. Why the airplane landed where it did, when it did, and how fast it did are the relevant questions.
People should stop doing this. Transport category airplanes are designed to suffer multiple failures and still be controllable. Why the airplane landed where it did, when it did, and how fast it did are the relevant questions.
I do not think speculations on HN are impacting the investigation in any way, shape or form, although I understand your perspective.
I do hope the investigation yields results that improve air travel safety.
I do hope the investigation yields results that improve air travel safety.
>I do not think speculations on HN are impacting the investigation
They are and will negatively impact the final impression of the investigation results, namely an unwarranted focus on The Wall(tm) (people here are calling it the "Murder Wall", which demonstrates my point) which helps precisely noone.
The focus should primarily be on the plane, particularly in the interests of preventing a repeat.
They are and will negatively impact the final impression of the investigation results, namely an unwarranted focus on The Wall(tm) (people here are calling it the "Murder Wall", which demonstrates my point) which helps precisely noone.
The focus should primarily be on the plane, particularly in the interests of preventing a repeat.
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 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.
Agreed. I work on a different type of vehicle with safety-critical systems for a living, and I'm naturally also very interested in the interactions between the pilots and the machine (and among themselves) and the spiral of events in the cockpit.
But that doesn't mean debating whether there's a better way to engineer typhoon-resilient localizer antenna arrays isn't also a good use of time. Safety makes it imperative to discuss all of these matters exhaustively.
Re ocean, no, that isn't so great - sea rescue is a lot more difficult to perform than on land.
But that doesn't mean debating whether there's a better way to engineer typhoon-resilient localizer antenna arrays isn't also a good use of time. Safety makes it imperative to discuss all of these matters exhaustively.
Re ocean, no, that isn't so great - sea rescue is a lot more difficult to perform than on land.
Sure but if you have 3km of open water following the runway then don’t block it with a concrete wall (even if that wall prevents storm flooding 2 days every 5 years). Sea rescue is a lot easier than rescuing people who drove into a concrete wall.
> If you are lucky enough to have empty fields but put a concrete wall there ...
I am fairly sure this will be one of the findings of the investigation. I hazard a guess that every sane operator of an airport in the world is walking from the end of their runway to the airfield perimeter and taking a look anyway.
I am fairly sure this will be one of the findings of the investigation. I hazard a guess that every sane operator of an airport in the world is walking from the end of their runway to the airfield perimeter and taking a look anyway.
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_...
https://en.wikipedia.org/wiki/Engineered_materials_arrestor_...
The wall might critical to keeping things off the runway, like animals and people.
This one isn't. It's a relatively short support structure, not a battlement.
There are cinderblock a cinderblock wall and numerous chin-link (and razor-wire-topped) fences in the area, which do control airport access. Those would likely not have proved fatal to the aircraft to any similar extent however.
There are cinderblock a cinderblock wall and numerous chin-link (and razor-wire-topped) fences in the area, which do control airport access. Those would likely not have proved fatal to the aircraft to any similar extent however.
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 possible. More than one may have happened. Wait for the flight data recorder data.
One article says the runway was equipped with EMAS, an Engineered Materials Arresting System.[1] This sits in the area just past the end of the runway, the part marked with painted chevrons. It's a thin layer of concrete over blocks of a material which includes foamed plastic holding pumice-like rocks. If a plane overruns the runway, the wheels break through the thin concrete layer and start pushing through the plastic/rock mixture, grinding the rocks into powder to absorb the energy. This usually damages the landing gear, but the rest of the plane survives. 22 planes saved so far.[2][3]
It didn't help here. The plane seems to have skidded over the EMAS area on its belly, instead of breaking through and getting the braking effect. The surface of the EMAS area has to be tough enough to survive jet blast on takeoffs, so it can't just be a sand pit.
[1] https://focustaiwan.tw/society/202412300010
[2] https://ops.group/blog/swerving-to-avoid-why-arent-we-using-...
[3] https://www.faa.gov/newsroom/engineered-material-arresting-s...
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 possible. More than one may have happened. Wait for the flight data recorder data.
One article says the runway was equipped with EMAS, an Engineered Materials Arresting System.[1] This sits in the area just past the end of the runway, the part marked with painted chevrons. It's a thin layer of concrete over blocks of a material which includes foamed plastic holding pumice-like rocks. If a plane overruns the runway, the wheels break through the thin concrete layer and start pushing through the plastic/rock mixture, grinding the rocks into powder to absorb the energy. This usually damages the landing gear, but the rest of the plane survives. 22 planes saved so far.[2][3]
It didn't help here. The plane seems to have skidded over the EMAS area on its belly, instead of breaking through and getting the braking effect. The surface of the EMAS area has to be tough enough to survive jet blast on takeoffs, so it can't just be a sand pit.
[1] https://focustaiwan.tw/society/202412300010
[2] https://ops.group/blog/swerving-to-avoid-why-arent-we-using-...
[3] https://www.faa.gov/newsroom/engineered-material-arresting-s...
> 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.
> 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.
Oh, you're right. Different airport. Sorry.
Muan does have the chevron markings on the overrun area, but that does not always indicate EMAS.
Muan does have the chevron markings on the overrun area, but that does not always indicate EMAS.
It does seem unlikely to me that a surface designed to give under the pressure of an aircraft wheels’ contact patch would function as designed under the comparatively lower pressure of an aircraft skidding along its belly.
It is clear that the main cause of the disaster was the landing in the middle of the runway and at excessive speed. However, if instead of that concrete wall there had been, for example, an extension of the runway filled with some material that could help dissipate the kinetic energy, perhaps the death toll would have been lower.
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 mandatory now and even ICAO acknowledged this very reason for the new regulations introduction.
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 mandatory now and even ICAO acknowledged this very reason for the new regulations introduction.
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 investigation report will conclude absence of localizer antennas wouldn't save them.
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 investigation report will conclude absence of localizer antennas wouldn't save them.
History says otherwise.
Most runway overruns occur with no or few fatalities:
<https://news.ycombinator.com/item?id=42606790>
Most runway overruns occur with no or few fatalities:
<https://news.ycombinator.com/item?id=42606790>
I looked into all of those and of the ones that had speeds available, they were half or less than half the speed at the time of overrun
Yes, because the speed was lower. Kinetic energy increases with speed squared. Uncontrolled 300 km/h on the ground kills you in any vehicle.
That's a fair argument, and I've noted the kinetic energy aspect elsewhere in this discussion.
That said, based on my observations of the terrain past the runway / airport threshold, it seems to me that absent the Muan Murder Wall, survivability would have been far higher in this case. See: <https://news.ycombinator.com/item?id=42607464>
I've yet to find a source that does a better job of organising incidents by landing speed / profile in a way which might better provide for more direct comparisons.
That said, based on my observations of the terrain past the runway / airport threshold, it seems to me that absent the Muan Murder Wall, survivability would have been far higher in this case. See: <https://news.ycombinator.com/item?id=42607464>
I've yet to find a source that does a better job of organising incidents by landing speed / profile in a way which might better provide for more direct comparisons.
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.
So survival chance of hitting a concrete wall and open field would be same?
I don't think so.
I don't think so.
[deleted]
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.
It's simply not possible to build airports in useful places and guarantee three-mile runways.
Apparently runaway excursions is the third cause of major accidents of large commercial transport aircraft [1].
Muan airport runway distance is one the shortest in Korea, less than 3 km and ironically during the incident reportedly there is an ongoing construction to increase the length of the runaway to more than 3 km, but effectively further shorten the runaway to 2.5 km (similar to Yangyang Airport). Strangely South Korea has many shorter runway international airports.
Most of the modern international airport have more than 4 km runway, and new major airports for example Qatar Doha, US Denver and SA Upington has runaway length close to 5 km.
[1] Operational Landing Distances: A new standard for in-flight landing distance assessment.
[2] Muan Airport runway previously shortened, impact under scrutiny:
https://m.koreatimes.co.kr/pages/article.asp?newsIdx=389538
Muan airport runway distance is one the shortest in Korea, less than 3 km and ironically during the incident reportedly there is an ongoing construction to increase the length of the runaway to more than 3 km, but effectively further shorten the runaway to 2.5 km (similar to Yangyang Airport). Strangely South Korea has many shorter runway international airports.
Most of the modern international airport have more than 4 km runway, and new major airports for example Qatar Doha, US Denver and SA Upington has runaway length close to 5 km.
[1] Operational Landing Distances: A new standard for in-flight landing distance assessment.
[2] Muan Airport runway previously shortened, impact under scrutiny:
https://m.koreatimes.co.kr/pages/article.asp?newsIdx=389538
> new major airports for example Qatar Doha, US Denver and SA Upington has runaway length close to 5 km.
These are by no means average "new major airports".
Denver airport (from 1989) is the west's largest airport (by land area), and at 5000 ft+ elevation (necessitating longer runways).
Upington in the far North-West of South Africa was built in 1968 to accommodate a full Boeing 747 flying to Europe non-stop during the apartheid regime when sanctions meant that overflight or stops in the rest of Africa were not feasible. It has one of the longest runways in the world due to the use case and hot & high environment at 2800 ft (and was intended as an emergency runway for Space Shuttles, if memory serves correctly). It is hardly used anymore with less than 20 aircraft movements a day.
There is no recent trend for longer runways. The issue is extremely well known and well understood, by and large.
These are by no means average "new major airports".
Denver airport (from 1989) is the west's largest airport (by land area), and at 5000 ft+ elevation (necessitating longer runways).
Upington in the far North-West of South Africa was built in 1968 to accommodate a full Boeing 747 flying to Europe non-stop during the apartheid regime when sanctions meant that overflight or stops in the rest of Africa were not feasible. It has one of the longest runways in the world due to the use case and hot & high environment at 2800 ft (and was intended as an emergency runway for Space Shuttles, if memory serves correctly). It is hardly used anymore with less than 20 aircraft movements a day.
There is no recent trend for longer runways. The issue is extremely well known and well understood, by and large.
Denver needs a longer runway because of its altitude. Doha because of the temperatures. It makes no sense to compare their length with locations at more favorable locations.
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>
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.
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.
When the wings come off, you get a pretty big fire though. Obviously they cannot be made infinitely strong, but I'd rather be in the plane that isn't disintegrating and in fire.
Armouring wings against fuel-system penetration (tanks, hoses, valves, etc.) in a mishap is an absolutely insane level of engineering, and all but certainly infeasible.
The much more reasonable alternative is to have 1) fuel-dumping systems which rid the craft of excess fuel prior to an emergency landing (another reason, BTW, to remain aloft as long as possible after an emergency has been declared), and 2) to have the means to evacuate the aircraft quickly. Modern standard is 90 seconds, with only half the exits in use. Initial fireballs, whilst impressive, usually occur largely above the aircraft and direct heat upwards. It's the subsequent ground- and cabin-based fires which are most lethal, and those tend not to develop for about two minutes.
<https://simpleflying.com/aircraft-90-second-evacuation/>
After that, you want the actual fuselage and passenger restraint systems (seats, seat belts) to provide maximum protection against injury in the crash itself. They largely do this. At least when aircraft aren't encountering Muan Murder Walls at speeds well in excess of 100 kt and disintegrating fully.
The much more reasonable alternative is to have 1) fuel-dumping systems which rid the craft of excess fuel prior to an emergency landing (another reason, BTW, to remain aloft as long as possible after an emergency has been declared), and 2) to have the means to evacuate the aircraft quickly. Modern standard is 90 seconds, with only half the exits in use. Initial fireballs, whilst impressive, usually occur largely above the aircraft and direct heat upwards. It's the subsequent ground- and cabin-based fires which are most lethal, and those tend not to develop for about two minutes.
<https://simpleflying.com/aircraft-90-second-evacuation/>
After that, you want the actual fuselage and passenger restraint systems (seats, seat belts) to provide maximum protection against injury in the crash itself. They largely do this. At least when aircraft aren't encountering Muan Murder Walls at speeds well in excess of 100 kt and disintegrating fully.
> The wall is a red herring.
This is not how safety works.
> Something bad is going to happen if you do that at any runway on earth.
Then the question is can we do any sort of engineering to reduce the number of fatalities that might occur when this _inevitably_ happens.
> Stop looking at the wall and look at the minutes before the crash.
The plane hit the wall and exploded. The wall seems pretty important here. I mean, yes, there are also other problems to solve, but solving them does not let you off the hook here.
This is not how safety works.
> Something bad is going to happen if you do that at any runway on earth.
Then the question is can we do any sort of engineering to reduce the number of fatalities that might occur when this _inevitably_ happens.
> Stop looking at the wall and look at the minutes before the crash.
The plane hit the wall and exploded. The wall seems pretty important here. I mean, yes, there are also other problems to solve, but solving them does not let you off the hook here.
You could mandate that airports incorporate runways shaped as disks with 10 km diameter and another 5 km of empty space around them.
Accidents would still happen.
Accidents would still happen.
Many runways have an ILS antenna installation inside the protected area. They just follow code guidelines that the mounts can only be so high above grade and must be frangible. This installation is different because of local conditions. They used a common local solution in an inappropriate area.
There are dozens of ways to solve this problem. From the short term of better structure engineering to the long term of better ILS antenna installations that don't require such large structures in such commonly dangerous positions in the first place. We could even get into better run off engineering to handle the somewhat unusual case of a fully gear up landing.
It's just insane to me to say "it's a red herring" as if this were a mystery novel and not an emergent failure of several safety mechanisms.
There are dozens of ways to solve this problem. From the short term of better structure engineering to the long term of better ILS antenna installations that don't require such large structures in such commonly dangerous positions in the first place. We could even get into better run off engineering to handle the somewhat unusual case of a fully gear up landing.
It's just insane to me to say "it's a red herring" as if this were a mystery novel and not an emergent failure of several safety mechanisms.
Your suggestion is absurd and impractical. You’re not contributing anything useful. Of course accidents happen. Knowing accidents happen, People are asking why a large solid concrete structure is at the end of the runway. Especially given that it was known to be a bad idea.
> In SFO you'll end up in the bay or hit the terminal depending on the orientation.
The bay is survivable and I don't think you can hit the terminal. You could possibly hit the freeway though. That said, two of the runways at SFO are 1.5 km longer than the one in Korea.
> In Toronto you'll crash into a highway.
That runway is 1.5 kilometers longer than the one in Korea and it's another kilometer to the highway that sits uphill.
The bay is survivable and I don't think you can hit the terminal. You could possibly hit the freeway though. That said, two of the runways at SFO are 1.5 km longer than the one in Korea.
> In Toronto you'll crash into a highway.
That runway is 1.5 kilometers longer than the one in Korea and it's another kilometer to the highway that sits uphill.
In Toronto, the 427 is ~100m from the edge of 24R.
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.
I don’t think so. Would the localizer have been made of less rigid structure and not a steel-reinforced concrete, the fatality could be much lower. Also problematic is the brick wall at the end. They could make it as fence only and not a brick wall. That will help, too.
Of course, one need to investigate the whole situation, for example why did the pilot choose to land immediately, why no flaps and spoilers were released and why no attempt has been made to manually release the landing gears (using gravity if needed) are things of intense scrutiny now.
People keep saying that, but I don't see how it's excusable for there to be a massive concrete block against which planes disintegrate at the end of any runway. Maybe everybody would've died some other way, maybe only 10 people would have survived, who knows. But we won't know because somebody put a massive concrete block in the way.
We aren't talking about any of your examples in this crash. And it isn't relevant for many other places either. If you have an open field behind a runway and you put a concrete block directly at the end of it, you can't defend your decision with "well, in this other city it doesn't matter because you'll hit the terminal". It's some weird form of whataboutism that I simply don't understand.
It's inexcusable and it's tiring seeing people defend it as if it's okay.
We aren't talking about any of your examples in this crash. And it isn't relevant for many other places either. If you have an open field behind a runway and you put a concrete block directly at the end of it, you can't defend your decision with "well, in this other city it doesn't matter because you'll hit the terminal". It's some weird form of whataboutism that I simply don't understand.
It's inexcusable and it's tiring seeing people defend it as if it's okay.
Apparently it is a structure that holds antennas to keep an aircraft centered on the runway. The antennas have to be there, but experts are saying that the structure supporting the antennas is way over engineered and even internal airport documents had raised concerns about it:
https://www.pbs.org/newshour/show/south-korean-officials-wer...
https://www.pbs.org/newshour/show/south-korean-officials-wer...
Yes, especially because the concrete block is against regulations.
A terminal beside the runway at roughly the same distance is not against regulations.
Almost every rule in aviation is written in blood, so if there's a rule about something, there's probably a damn good reason why.
A terminal beside the runway at roughly the same distance is not against regulations.
Almost every rule in aviation is written in blood, so if there's a rule about something, there's probably a damn good reason why.
Exactly.
Causality isn’t an equivalence relation with blame. A moral aspect has to be established.
Causality isn’t an equivalence relation with blame. A moral aspect has to be established.
If you can get the same features with less risk it seems like a worthwhile thing to consider.
Meaning if we can build the same antenna array but with less risk to airplanes and all at an acceptable economical cost, it feels like something we should do. Regardless of whether or not a runway overrun at other airports and in other situations poses more or less risk.
Meaning if we can build the same antenna array but with less risk to airplanes and all at an acceptable economical cost, it feels like something we should do. Regardless of whether or not a runway overrun at other airports and in other situations poses more or less risk.
This crash raises two separate questions: why did the airplane land the way it did, and did it make any sense to have a massive concrete barrier just off the end of the runway. The answer to either one does not render the other irrelevant. As it happens, we already know the answer to one of them.
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.
> 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.
Terminals are generally located to the side of a runway at some distance, where a plane aligned with the runway is unlikely to hit them no matter how fast it's going.
Not sure if there's a regulation that requires this kind of arrangement, but I wouldn't be surprised if there are stricter rules about structures that cross a plane's usual trajectory.
Not sure if there's a regulation that requires this kind of arrangement, but I wouldn't be surprised if there are stricter rules about structures that cross a plane's usual trajectory.
This is a slippery slope that leads to infinitely long runways.
Any length of runway you agree on can still fail. As you just said, it's an eventual certainty.
Rather than fixating on what didn't cause the crash how about we spend that energy on finding out why this flight unlike 99.99% of flights couldn't stop in the allotted space.
If they were gonna land halfway down the runway why didn't they just do another go-around? Did the thrust reversers not work? Doesn't the 737-800 have a backup way of dropping the landing gear?
Any length of runway you agree on can still fail. As you just said, it's an eventual certainty.
Rather than fixating on what didn't cause the crash how about we spend that energy on finding out why this flight unlike 99.99% of flights couldn't stop in the allotted space.
If they were gonna land halfway down the runway why didn't they just do another go-around? Did the thrust reversers not work? Doesn't the 737-800 have a backup way of dropping the landing gear?
Crashing into a highway would have resulted in similar loss of life. Airplanes are only barely safe when they land without gear, and almost any obstruction is going to be more solid than a machine that's built to be as lightweight as possible.
There is no way to make a runway safe if a plane lands halfway down it, even if the brakes and landing gear are actually working. It's just not possible; runways are limited by geography and we tend to run aircraft as heavy as possible.
There is no way to make a runway safe if a plane lands halfway down it, even if the brakes and landing gear are actually working. It's just not possible; runways are limited by geography and we tend to run aircraft as heavy as possible.
I recall one from long ago where there was a fuel storage tank off the end of the runway. I don't think there were any survivors.
Terrible take, wall is not the red herring, wall is the reason of deaths of almost all souls in the plane. "Something bad is going to happen" usually has very different outcome than hitting a concrete wall.
Aviation accident history definitely disagrees with you.
Aviation accident history definitely disagrees with you.
This exactly. The biggest problem was that it came down with no gear or flaps (as far as I'm aware at least).
No one is discouraging investigation of the other factors or thinks they aren't significant.
Except they are and they do. The quoted "air safety expert" in the BBC article essentially says the landing was "as good as can be" and that most or all of the people onboard would have survived if the localizer berm wasn't present.
Are you this "air safety expert" is part of the investigation team? Because otherwise, I don't think the actual investigators care about their opinion, or yours, or that of any media (mainstream or not)...
The full quote you're referencing but truncating is "as good as a flapless/gearless touchdown could be." This is, uh, light praise? "It's a pretty great shit sandwich."
None of these people are calling for not investigating the other factors.
None of these people are calling for not investigating the other factors.
Nowhere else on earth is that structure a concrete wall. Its always some rather flimsy metal structure- designed to crumble.
At the moment before encountering the Muan Murder Wall, there were 181 souls alive, healthy, and uninjured aboard Jeju Air Flight 2216.
At the moment after encountering the Muan Murder Wall, there were 2 souls alive, one severely injured, and 179 corpses, most mutilated beyond all recognition.
Multiple things had clearly gone wrong with the flight, and we're going to have to wait for results of investigations to determine what crew and/or ATC actions and decisions contributed. But the principle lethal mechanism was impact with the immovable object of the Muan Murder Wall, and the ensuing instantaneous deceleration, disintegration, and conflagration of the aircraft and the souls aboard.
Even with multiple contributing factors, had the Muan Murder Wall not existed at that location, the aircraft would have overrun the runway and quite possibly airport perimeter, but would have slowed far more gradually and likely encountered structures less substantial than the Muan Murder Wall.
Wikipedia has a category page listing 55 runway overruns: <https://en.wikipedia.org/wiki/Category:Airliner_accidents_an...>
Sampling from that we find that such accidents often result in no or few fatalities, particularly on landing. E.g.:
- Sriwijaya Air Flight 062 (2008): 130 souls, 124 passengers, 6 crew, 1 fatality, 23 injuries, 130 survivors. The aircraft struck a house, 3 of the injured were occupants. The sole fatality occurred some time after the incident. <https://en.wikipedia.org/wiki/Sriwijaya_Air_Flight_062>
- China Eastern Airlines Flight 5398 (1993): 80 souls, 71 passengers, 9 crew, 2 fatalities, 10 injuries, 78 survivors. The aircraft experienced a tailstrike during a go-around attempt in heavy rain / high winds, broke in three, and came to rest in a pond. <https://en.wikipedia.org/wiki/China_Eastern_Airlines_Flight_...>
- Philippine Airlines Flight 137 (1998): 130 souls, 124 passengers, 6 crew, 0 fatalities, 44 injuries, 130 survivors. Ground casualties: 3 dead, 25 injured, as aircraft ploughed through a residential area. <https://en.wikipedia.org/wiki/Philippine_Airlines_Flight_137>
- American Airlines Flight 331 (2009): 154 souls, 148 passengers, 6 crew, 0 fatalities, 85 injuries, 154 survivors. Aircraft landed > 4,000 feet from the threshold with a tailwind in inclement weather. <https://en.wikipedia.org/wiki/American_Airlines_Flight_331>
- TAM Airlines Flight 3054 (2007): 187 occupants, 181 passengers, 6 crew, 187 fatalities, 0 survivors. The exception in my (random) sample, this aircraft had a nonfunctional thrust reverser on the right engine. Lack of grooving on runway, heavy rain, hydroplaning, asymmetric thrust, and a large warehouse directly beyond the runway perimeter all contributed to the fatalities.
I've omitted one link I'd selected, Air France Flight 007 (1962) as that incident occurred on takeoff, not landing, where fuel load and flight profile greatly alter conditions and likely outcome, and isn't directly comparable. <https://en.wikipedia.org/wiki/Air_France_Flight_007>.
If anyone cares to examine the 50 other listings on the Wikipedia category page, I suspect a similar patter of largely survivable overrun incidents prevails. The conspicuous lack of Muan Murder Walls seems significant.
At the moment after encountering the Muan Murder Wall, there were 2 souls alive, one severely injured, and 179 corpses, most mutilated beyond all recognition.
Multiple things had clearly gone wrong with the flight, and we're going to have to wait for results of investigations to determine what crew and/or ATC actions and decisions contributed. But the principle lethal mechanism was impact with the immovable object of the Muan Murder Wall, and the ensuing instantaneous deceleration, disintegration, and conflagration of the aircraft and the souls aboard.
Even with multiple contributing factors, had the Muan Murder Wall not existed at that location, the aircraft would have overrun the runway and quite possibly airport perimeter, but would have slowed far more gradually and likely encountered structures less substantial than the Muan Murder Wall.
Wikipedia has a category page listing 55 runway overruns: <https://en.wikipedia.org/wiki/Category:Airliner_accidents_an...>
Sampling from that we find that such accidents often result in no or few fatalities, particularly on landing. E.g.:
- Sriwijaya Air Flight 062 (2008): 130 souls, 124 passengers, 6 crew, 1 fatality, 23 injuries, 130 survivors. The aircraft struck a house, 3 of the injured were occupants. The sole fatality occurred some time after the incident. <https://en.wikipedia.org/wiki/Sriwijaya_Air_Flight_062>
- China Eastern Airlines Flight 5398 (1993): 80 souls, 71 passengers, 9 crew, 2 fatalities, 10 injuries, 78 survivors. The aircraft experienced a tailstrike during a go-around attempt in heavy rain / high winds, broke in three, and came to rest in a pond. <https://en.wikipedia.org/wiki/China_Eastern_Airlines_Flight_...>
- Philippine Airlines Flight 137 (1998): 130 souls, 124 passengers, 6 crew, 0 fatalities, 44 injuries, 130 survivors. Ground casualties: 3 dead, 25 injured, as aircraft ploughed through a residential area. <https://en.wikipedia.org/wiki/Philippine_Airlines_Flight_137>
- American Airlines Flight 331 (2009): 154 souls, 148 passengers, 6 crew, 0 fatalities, 85 injuries, 154 survivors. Aircraft landed > 4,000 feet from the threshold with a tailwind in inclement weather. <https://en.wikipedia.org/wiki/American_Airlines_Flight_331>
- TAM Airlines Flight 3054 (2007): 187 occupants, 181 passengers, 6 crew, 187 fatalities, 0 survivors. The exception in my (random) sample, this aircraft had a nonfunctional thrust reverser on the right engine. Lack of grooving on runway, heavy rain, hydroplaning, asymmetric thrust, and a large warehouse directly beyond the runway perimeter all contributed to the fatalities.
I've omitted one link I'd selected, Air France Flight 007 (1962) as that incident occurred on takeoff, not landing, where fuel load and flight profile greatly alter conditions and likely outcome, and isn't directly comparable. <https://en.wikipedia.org/wiki/Air_France_Flight_007>.
If anyone cares to examine the 50 other listings on the Wikipedia category page, I suspect a similar patter of largely survivable overrun incidents prevails. The conspicuous lack of Muan Murder Walls seems significant.
And for the details of the Muan Murder Wall itself.
Here's Google Maps view of the area south of Muan airport:
<https://www.google.com/maps/@34.9731352,126.3829389,1299m/da...>
From a road directly outside the airport, looking toward the ILS structure, we see that had the wall itself not been there the plane would have struck a cinderblock wall as it continued on. This would have damaged the aircraft, but less so than a solid concrete wall:
<https://maps.app.goo.gl/mMGqBC9PX6sEF85B9>
Switching directions we can look to the south along the path the aircraft would likely have followed. The terrain is flat and clear, save for further navigation light structures which would likely have given way readily to the aircraft:
<https://maps.app.goo.gl/Retvh9MH48ta5xPS8>
Note a hill in the distance. This could have helped slow the aircraft further, gently:
<https://maps.app.goo.gl/m1D3WrMG5QYz6cvE8> (above image zoomed in).
Vegetation is low trees and shrubs, which again could have provided a fairly gentle stopping force against the airframe:
<https://maps.app.goo.gl/aCBtY9at1Q1oCZXz6>
Approximately 300m or so from the end of the runway are a few rather unwisely-located pensions and hotels. Those would likely contribute to ground casualties if impacted.
Another few metres past those, mudlands and bay waters, which would be more emenable to a survivable overrun.
Here's Google Maps view of the area south of Muan airport:
<https://www.google.com/maps/@34.9731352,126.3829389,1299m/da...>
From a road directly outside the airport, looking toward the ILS structure, we see that had the wall itself not been there the plane would have struck a cinderblock wall as it continued on. This would have damaged the aircraft, but less so than a solid concrete wall:
<https://maps.app.goo.gl/mMGqBC9PX6sEF85B9>
Switching directions we can look to the south along the path the aircraft would likely have followed. The terrain is flat and clear, save for further navigation light structures which would likely have given way readily to the aircraft:
<https://maps.app.goo.gl/Retvh9MH48ta5xPS8>
Note a hill in the distance. This could have helped slow the aircraft further, gently:
<https://maps.app.goo.gl/m1D3WrMG5QYz6cvE8> (above image zoomed in).
Vegetation is low trees and shrubs, which again could have provided a fairly gentle stopping force against the airframe:
<https://maps.app.goo.gl/aCBtY9at1Q1oCZXz6>
Approximately 300m or so from the end of the runway are a few rather unwisely-located pensions and hotels. Those would likely contribute to ground casualties if impacted.
Another few metres past those, mudlands and bay waters, which would be more emenable to a survivable overrun.
I'm going through more of the Wikipedia category entries.
AA 1420 (1999) is notable for similarities with Jeju 2216:
The aircraft continued past the end of the runway, traveling another 800 feet (240 m; 270 yd), and striking a security fence and an ILS localizer array. The aircraft then collided with a structure built to support the approach lights for Runway 22L, which extended out into the Arkansas River. Such structures are usually frangible, designed to shear off on impact, but because the approach lights were located on the unstable river bank, they were firmly anchored. The collision with the sturdy structure crushed the airplane's nose, and destroyed the left side of the plane's fuselage, from the cockpit back to the first two rows of coach seating. The impact broke the aircraft apart into large sections, which came to a rest short of the river bank.
Captain Buschmann and 8 of the plane's 139 passengers were immediately killed in the crash; another two passengers died in the hospital in the weeks that followed.
145 souls, 139 pax, 6 crew, 11 fatalities, 110 injured, 134 survivors.
<https://en.wikipedia.org/wiki/American_Airlines_Flight_1420>
Even though this aircraft also hit an ILS structure, fatalities were far lower than those of Jeju 2216, likely as AA 1420 had decelerated significantly both on the runway (despite severely limited wheel and air brakes) and its subsequent 240 cross-terrain slide.
Atlantic Airways Flight 670 (2006) literally fell off a cliff. 4 fatalities of 16 souls. <https://en.wikipedia.org/wiki/Atlantic_Airways_Flight_670>
Bangkok Airways Flight 266 (2009) literally struck a (presumably nonfrangible) control tower. 1 fatality, 71 souls. <https://en.wikipedia.org/wiki/Bangkok_Airways_Flight_266>
AA 1420 (1999) is notable for similarities with Jeju 2216:
The aircraft continued past the end of the runway, traveling another 800 feet (240 m; 270 yd), and striking a security fence and an ILS localizer array. The aircraft then collided with a structure built to support the approach lights for Runway 22L, which extended out into the Arkansas River. Such structures are usually frangible, designed to shear off on impact, but because the approach lights were located on the unstable river bank, they were firmly anchored. The collision with the sturdy structure crushed the airplane's nose, and destroyed the left side of the plane's fuselage, from the cockpit back to the first two rows of coach seating. The impact broke the aircraft apart into large sections, which came to a rest short of the river bank.
Captain Buschmann and 8 of the plane's 139 passengers were immediately killed in the crash; another two passengers died in the hospital in the weeks that followed.
145 souls, 139 pax, 6 crew, 11 fatalities, 110 injured, 134 survivors.
<https://en.wikipedia.org/wiki/American_Airlines_Flight_1420>
Even though this aircraft also hit an ILS structure, fatalities were far lower than those of Jeju 2216, likely as AA 1420 had decelerated significantly both on the runway (despite severely limited wheel and air brakes) and its subsequent 240 cross-terrain slide.
Atlantic Airways Flight 670 (2006) literally fell off a cliff. 4 fatalities of 16 souls. <https://en.wikipedia.org/wiki/Atlantic_Airways_Flight_670>
Bangkok Airways Flight 266 (2009) literally struck a (presumably nonfrangible) control tower. 1 fatality, 71 souls. <https://en.wikipedia.org/wiki/Bangkok_Airways_Flight_266>
I looked up the AA 1420 crash report (linked from Wikipedia) and it says:
https://www.ntsb.gov/investigations/AccidentReports/Reports/...
> The calculated ground trajectory indicated that the flight 1420 airplane departed runway 4R at about 97 knots and impacted the runway 22L approach lighting system support structure at about 83 knots.
97 knots is 112 mph. Somewhere below another commenter said Jeju Air 2216 left the runway at about 160 knots (184 mph). It's a pretty big difference.
I'm no expert, but my guess is that the main distinguishing factor of all the accidents where most/all survived is not the lack of killer berms, but the speed of the plane when it left the runway.
https://www.ntsb.gov/investigations/AccidentReports/Reports/...
> The calculated ground trajectory indicated that the flight 1420 airplane departed runway 4R at about 97 knots and impacted the runway 22L approach lighting system support structure at about 83 knots.
97 knots is 112 mph. Somewhere below another commenter said Jeju Air 2216 left the runway at about 160 knots (184 mph). It's a pretty big difference.
I'm no expert, but my guess is that the main distinguishing factor of all the accidents where most/all survived is not the lack of killer berms, but the speed of the plane when it left the runway.
1420 airplane departed runway 4R at about 97 knots and impacted the runway 22L approach lighting system support structure at about 83 knots.
That's a more explicit restatement of my own "likely as AA 1420 had decelerated significantly both on the runway ... and its subsequent 240 cross-terrain slide."
Jeju 2216's lack of braking authority may have resulted from a dual engine outage, possibly a consequence of pilot error, noted here:
<https://news.ycombinator.com/item?id=42605837>
Absent the ILS structure, the aircraft would have had ~300-500m to decelerate across largely forgiving terrain before possibly encountering fairly light structures, and ultimately bay waters, detailed here:
<https://news.ycombinator.com/item?id=42607464>
As I've noted already, we're waiting on investigation conclusions to understand further, though it's entertaining to speculate, and IMO somewhat more productive to look at similar events and history.
That's a more explicit restatement of my own "likely as AA 1420 had decelerated significantly both on the runway ... and its subsequent 240 cross-terrain slide."
Jeju 2216's lack of braking authority may have resulted from a dual engine outage, possibly a consequence of pilot error, noted here:
<https://news.ycombinator.com/item?id=42605837>
Absent the ILS structure, the aircraft would have had ~300-500m to decelerate across largely forgiving terrain before possibly encountering fairly light structures, and ultimately bay waters, detailed here:
<https://news.ycombinator.com/item?id=42607464>
As I've noted already, we're waiting on investigation conclusions to understand further, though it's entertaining to speculate, and IMO somewhat more productive to look at similar events and history.
You are missing the point. Runways are supposed to provide some room for errors. It's part of the investigation. You can't simply blame a human. Everything needs to be designed just in case
Disagree from Hong Kong. You would probably land on sea but probably end up with single digit causalities
Most of the busiest airports in the world have some sort of dangerous obstacle roughly the same distance from many of their runways. Ravines, buildings, hills, water, trains/trams, etc, etc.
But not this one. Not this one. Without the wall, it's likely many more would be alive.
Yes, this one. Just like the others, this airport had a dangerous obstacle at a considerable distance from the runway. It's not a design goal of these runways to make such a landing survivable.
Except this dangerous obstacle did not need to be there. It could and should have been mounted on frangible posts, not on solid concrete.
Indeed, this one. But was it known to the pilots? The other dangerous obstacles you mention tend to be known and visible, not hidden and unexpected (against best practices).
The pilots didn't have to land there, they could have attempted a US Airways Flight 1549 rather than aiming at a piece of reinforced concrete.
The pilots didn't have to land there, they could have attempted a US Airways Flight 1549 rather than aiming at a piece of reinforced concrete.
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 been the treeline or something else. That plane was doomed, concrete construction or not.> 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.
(Assuming the math is correct:) That's the average speed over that distance. The plane would have been slowing down the whole time.
(Assuming the math is correct:) That's the average speed over that distance. The plane would have been slowing down the whole time.
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 is based on velocity squared, so every bit helps a lot.
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 is based on velocity squared, so every bit helps a lot.
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.
Or as an adult. I am on a diet though.
Set yourself a goal!
And good news! A fully-loaded 737-800 has a maximum takeoff weight of less than 80 tonnes, not thousands, so your challenge is much more attainable!
<https://en.wikipedia.org/wiki/Boeing_737_Next_Generation#Spe...>
And good news! A fully-loaded 737-800 has a maximum takeoff weight of less than 80 tonnes, not thousands, so your challenge is much more attainable!
<https://en.wikipedia.org/wiki/Boeing_737_Next_Generation#Spe...>
Yeah I always overestimate those things by far :)
[deleted]
[deleted]
It might not have been slowing down much in that time due to a thing called Ground Effect. Since the wheels weren't down, the flat body of the bottom of the aircraft + wings would have actually reduced drag and cushioned the plane for a bit, causing it to not slow down as much as you would assume.
I'm not a pilot.
In the video it looked like the plane was only running on the rear landing gears, I assume with no brakes applied, since that would've caused it to violently pitch down I assume. Only in the last bit did it pitch down and started scraping along the runway. It certainly doesn't look like it was efficiently shedding speed (but looks can be deceiving).
In the video it looked like the plane was only running on the rear landing gears, I assume with no brakes applied, since that would've caused it to violently pitch down I assume. Only in the last bit did it pitch down and started scraping along the runway. It certainly doesn't look like it was efficiently shedding speed (but looks can be deceiving).
> In the video it looked like the plane was only running on the rear landing gears,
Are we talking about the same crash? In the video I have seen[1] the plane appears to be on its belly dragging on the runway.
1: https://www.youtube.com/watch?v=qJY7oaZpxDU
Are we talking about the same crash? In the video I have seen[1] the plane appears to be on its belly dragging on the runway.
1: https://www.youtube.com/watch?v=qJY7oaZpxDU
True! I misremembered, in the longer video it's hard to see that the nacelles are dragging on the ground all the way. Still doesn't seem to slow down much.
It was in gound effect floating till very near the end, these two video show the story very well: https://x.com/vinfly4/status/1873285591900836307 https://www.reddit.com/r/aviation/comments/1hopl7d/longer_vi...
As you can see, it actually isn't touching the ground for quite some time, it looks like it because one of the engines is smoking and the plane is throwing up dust etc from the ground as it floats above. Pure guessing on my part as someone who isn't involved in aviation but spent a good 6 hours looking into this crash: Pilots tried to go around, put the plane in go around config, couldn't, didn't know what to do, and watched the berm come at them. Extremely sad.
How both engines failed? We won't know til blackbox I guess, either pilot error or the bird strike was nuts and took out both engines, also some speculation the go around thrust caused a compressor stall. It looks to my uneducated eyes, from the first video, the left engine is not in great shape. Either way, very awful situation.
As you can see, it actually isn't touching the ground for quite some time, it looks like it because one of the engines is smoking and the plane is throwing up dust etc from the ground as it floats above. Pure guessing on my part as someone who isn't involved in aviation but spent a good 6 hours looking into this crash: Pilots tried to go around, put the plane in go around config, couldn't, didn't know what to do, and watched the berm come at them. Extremely sad.
How both engines failed? We won't know til blackbox I guess, either pilot error or the bird strike was nuts and took out both engines, also some speculation the go around thrust caused a compressor stall. It looks to my uneducated eyes, from the first video, the left engine is not in great shape. Either way, very awful situation.
The reason he touched down halfway down the runway could have been because the gear was up. If the gear was down, he would have touched down much earlier. He may not have known the gear was up, or did not account for the gear being up in his approach.
They executed a pretty difficult turn, apparently it's called the impossible tear drop and you're trained specifically NOT to ever do it. I looked at the flight tracking, I suspect the maneuver they pulled just put them at that point in the runway[1]. If you read my reply to the comment above you, it has some additional context you might find interesting. They pilots I watched all mentioned really, it doesn't make sense they cut off the approach, they should have taken the bird strike and continued the landing. The probable reasons given was: took evasive maneuvers to avoid the brids so came off glide slope, not enough engine power for a full go around, then started to get way behind the plane.
[1]https://s.france24.com/media/display/579312a0-c8cb-11ef-81bd...
[1]https://s.france24.com/media/display/579312a0-c8cb-11ef-81bd...
> it's called the impossible tear drop
Minor nit, I believe it’s called the teardrop go around for such cases. You also have the impossible turn which is meant typically for engine/power failure during takeoff, and it actually is possible to be safely done - as demonstrated by the former ALPA Air Safety Institute Senior VP Richard McSpadden in one of his YouTube videos.
However, it can be deceptively difficult to have the right conditions to pull it off - as demonstrated by the ironically fatal crash that killed Commander (Ret) McSpadden (though iirc it was not clear if he was flying the craft at the time).
(Edits made for clarity/content.)
Minor nit, I believe it’s called the teardrop go around for such cases. You also have the impossible turn which is meant typically for engine/power failure during takeoff, and it actually is possible to be safely done - as demonstrated by the former ALPA Air Safety Institute Senior VP Richard McSpadden in one of his YouTube videos.
However, it can be deceptively difficult to have the right conditions to pull it off - as demonstrated by the ironically fatal crash that killed Commander (Ret) McSpadden (though iirc it was not clear if he was flying the craft at the time).
(Edits made for clarity/content.)
Thank you for the clarification, I hoped I couched everything enough people knew I'm just reading internet and not at all an expert, I appreciate the reply!
Assuming that's true, would earlier ground contact have saved lives by slowing the plane more before colliding with the barrier?
I don't know if we could expect the pilot to know about or expect the barrier there.
I don't know if we could expect the pilot to know about or expect the barrier there.
Obviously hard to answer your question but if you're curious, some other bits of info I've gleaned from my autistic research mode. Some context: Bird strike was believed to be on engine 2, hydraulics are powered by engine 1. Few things seem fine as ideas to me - gear down at the speed they were going with the flaps stuck and thrust reversers sketchy, would probably cause under carriage separation, they're apparently trained to do a belly landing if they think this would happen as it's safer. The plane is in a 10/10 perfect config for a belly landing. (note: the config for belly landing and go around and extremely similar) Separately: The manual release requires you to unscrew something that takes about 60 seconds, and then violently swing the plane back and forth, pilot would not want to come off glide slope and even if they did, rocking the plane around at that low low altitude, not good. Separately: apparently in the time they turned, and crashed, there is no way they had time to run checklists, so they where according to the pilots I watched, probably just flying.
If the birds either took out both engines or engine 1 stalled under the load of engine 2 surging and dying (apparently common) - it seems to me they had no good options but to execute that tear drop turn that is apparently VERY MUCH not recommended as it's very very hard (but they did it) and get the plane down asap asap. Provided it's not pilot error and they shut down engine 1 in a panic by mistake (has happened before, fatally) - it seems they could very well have just gotten a very very very very bad, unlikely but possible, series of events. Makes me sad.
If the birds either took out both engines or engine 1 stalled under the load of engine 2 surging and dying (apparently common) - it seems to me they had no good options but to execute that tear drop turn that is apparently VERY MUCH not recommended as it's very very hard (but they did it) and get the plane down asap asap. Provided it's not pilot error and they shut down engine 1 in a panic by mistake (has happened before, fatally) - it seems they could very well have just gotten a very very very very bad, unlikely but possible, series of events. Makes me sad.
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.
That's under normal operation. All planes are certified to stop without any air reverse thrust[0] given they land at the right sized runway, right conditions, right position, etc etc.
But it's definitely part of the program.
They must also sit on the tarmac post heavy braking and the brakes must not burst into flames.
[0] https://www.youtube.com/watch?v=evLpE8Us-j0
But it's definitely part of the program.
They must also sit on the tarmac post heavy braking and the brakes must not burst into flames.
[0] https://www.youtube.com/watch?v=evLpE8Us-j0
True, though I don't have a breakdown of net effects.
Commercial jet aircraft utilise thrust reversers, speed (or air) brakes (usually control surfaces which can extend out from the aircraft fuselage or wings), and landing gear brakes.
The latter are not insignificant, but thrust reversers and speed brakes are major contributors, especially immediately after touchdown.
There's also the effect of spoilers which increase the load over the gear and hence the braking capabilities of landing gear brakes.
Jeju 2216 failed to utilise nearly all of these mechanisms. It landed without flaps, spoilers, or gear, and possibly w/o thrust reversers.
Commercial jet aircraft utilise thrust reversers, speed (or air) brakes (usually control surfaces which can extend out from the aircraft fuselage or wings), and landing gear brakes.
The latter are not insignificant, but thrust reversers and speed brakes are major contributors, especially immediately after touchdown.
There's also the effect of spoilers which increase the load over the gear and hence the braking capabilities of landing gear brakes.
Jeju 2216 failed to utilise nearly all of these mechanisms. It landed without flaps, spoilers, or gear, and possibly w/o thrust reversers.
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 used like that, so that's what thrust reversers are for.
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 used like that, so that's what thrust reversers are for.
That mass has much more velocity than a truck.
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.
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.
Some of them even move around the recommended touchdown point depending on other factors, if the runway is extra long.
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?
Do you believe the plane would have stayed in one piece if it wasn't for obstacles?
> 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.
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.
[deleted]
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.
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
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
Gears also aerobrake.
There were no flaps deployed. Without flaps it's going to be a lot faster than a normal landing.
Yes, it was a very fast landing.
just because that aircraft was doomed (maybe?), that doesn't make it a good idea to have the concrete wall there
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?
As an airline pilot, these are some of the questions I have. The flight data and cockpit voice recorders should be able to answer these questions.
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?
As an airline pilot, these are some of the questions I have. The flight data and cockpit voice recorders should be able to answer these questions.
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 issue with their safety culture.
Though, I am a little sceptical of the claims that it would have hugely reduced fatalities either way. Runway excursions into unmanaged terrain at that speed don't usually work out well for the passengers, even when the terrain appears relatively flat.
I'm not an airline pilot, but I'm still curious to see what caused such an unusual crash, since there doesn't seem to be any single issue that could have caused what happened. So far, my best uninformed guess is a combination of pilot error and bad luck: the approach wasn't stabilised, so they started executing a go-around, and THEN a multiple bird strike caused catastrophic damage to the right engine. This may have led to smoke in the cabin/cockpit which they interpreted as a fire (or some other issue, vibrations etc.) that made them decide to shut down the engine, but they shut down the wrong (left) engine. So now they think they have a dual engine failure. At this stage they obviously don't have time to run through paper procedures, and they put the plane into clean configuration to maximise glide and attempt a 180 to try and land back on the runway. Then they either couldn't or forgot to deploy the gear, and floated down the runway partly due to ground effect from being at an unusually high speed, thus landing at high speed almost halfway down the runway. Thoughts?
Though, I am a little sceptical of the claims that it would have hugely reduced fatalities either way. Runway excursions into unmanaged terrain at that speed don't usually work out well for the passengers, even when the terrain appears relatively flat.
I'm not an airline pilot, but I'm still curious to see what caused such an unusual crash, since there doesn't seem to be any single issue that could have caused what happened. So far, my best uninformed guess is a combination of pilot error and bad luck: the approach wasn't stabilised, so they started executing a go-around, and THEN a multiple bird strike caused catastrophic damage to the right engine. This may have led to smoke in the cabin/cockpit which they interpreted as a fire (or some other issue, vibrations etc.) that made them decide to shut down the engine, but they shut down the wrong (left) engine. So now they think they have a dual engine failure. At this stage they obviously don't have time to run through paper procedures, and they put the plane into clean configuration to maximise glide and attempt a 180 to try and land back on the runway. Then they either couldn't or forgot to deploy the gear, and floated down the runway partly due to ground effect from being at an unusually high speed, thus landing at high speed almost halfway down the runway. Thoughts?
"Normal Accidents" is a term for when things, well, normally go sideways in complex systems, and there's a whole book on it. Otherwise, it's pretty typical in disasters for there to be a laundry list of root causes and contributing factors: the Titanic was going too fast, there was hubris, and icebergs, and it was sad when the great boat went down. Could the disaster have been missed or been less bad if one or several factors had rolled up some other result? Maybe! That's what a full investigation is for, to suss out what went wrong and what things are most fixable.
A favourite! By Charles Perrow (1925-2019).
<https://en.wikipedia.org/wiki/Normal_Accidents>
<https://en.wikipedia.org/wiki/Normal_Accidents>
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.
By structure I meant the dirt mound with a concrete wall inside it, not the localizer. Entirely normal to have a localizer, but usually on a frangible structure if it needs to be elevated.
These were my thoughts exactly. Even if they lost all engines/power/hydraulics they would have had 8 mins to start up the APU so gear and flaps wouldn't have been an issue and clearly they still had some control. Did they try to go around and lose all power on the go? Gear up landings do happen in GA but I can't think of the last commercial aviation gear up landing. There will probably be a lot of useful things coming out of this. Changing design and placement of structures at the end of runways probably isn't a big one though.
Were those obstacles installed by the airport though? I thought it was like stuff on land outside of the airport for those other examples.
Does it matter? Either it's safe to have obstacles within 300m of the end of the runway, and this was a reasonable location for the Korean airport to put their localizer in, or it's not, and the likes of Burbank should shorten their runway to ensure there's sufficient buffer space at the end of it.
I’m suspicious of decontextualization in the name of forming “either X or Y” absolutes.
Either 8 character passwords are fine and secure, or bad and should be banned? With no context between “€x8;,O{w” and “password”?
I suspect runway design has more variables than just distance to obstacles.
Either 8 character passwords are fine and secure, or bad and should be banned? With no context between “€x8;,O{w” and “password”?
I suspect runway design has more variables than just distance to obstacles.
>and the likes of Burbank should shorten their runway to ensure there's sufficient buffer space at the end of it.
... you can't be serious with this? 300 more feet of unused runway is equivalent to if not better than 300 feet of buffer. You're fixated on following the "rules" without any understanding as to why they exist.
... you can't be serious with this? 300 more feet of unused runway is equivalent to if not better than 300 feet of buffer. You're fixated on following the "rules" without any understanding as to why they exist.
Yes, I'm being a bit facetious. I agree with you: there shouldn't be a hard rule of "no obstacles within 300m of the runway, and the Muan airport authorities were negligent in having one".
If they'd shortened the "runway" by 300m (let's say the unused space was still tarmacked and empty, but not designated as a runway, although I understand there are better materials for arresting overruns) would all those people still have died and would people still be blaming the airport layout?
Perhaps the pilot would have made a different decision if the runway was advertised as 2500m instead of 2800m, but that also suggests people are looking at the wrong thing, and pilots looking for emergency landings should consider not only the runway length but also any buffer available.
If they'd shortened the "runway" by 300m (let's say the unused space was still tarmacked and empty, but not designated as a runway, although I understand there are better materials for arresting overruns) would all those people still have died and would people still be blaming the airport layout?
Perhaps the pilot would have made a different decision if the runway was advertised as 2500m instead of 2800m, but that also suggests people are looking at the wrong thing, and pilots looking for emergency landings should consider not only the runway length but also any buffer available.
The localizer antenna mount (the concrete) was inside the airport perimeter. See diagram:
https://multimedia.scmp.com/embeds/2024/world/skorea-crash/i...
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.
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.
And if an accident occurred because a typhoon washed out the antenna, people would argue a concrete foundation would have been safer.
As an aside, this reminds of the consideration highway bureaus in the US give to trees and poles.[1] Trees are removed and poles should break easily and fall after a vehicle impact. This comes to mind because I have given most thought to these considerations as a pedestrian, regretting tree removals and feeling exposed to passing cars in a system designed to accommodate them safely (for them) departing the roadway anywhere, anytime. Of course, sometimes broken poles fall on cars or people, power outages are more routine especially after vehicular accidents, and there are other tradeoffs too, some of which are safety-related.
[1] https://safety.fhwa.dot.gov/roadway_dept/countermeasures/saf...
As an aside, this reminds of the consideration highway bureaus in the US give to trees and poles.[1] Trees are removed and poles should break easily and fall after a vehicle impact. This comes to mind because I have given most thought to these considerations as a pedestrian, regretting tree removals and feeling exposed to passing cars in a system designed to accommodate them safely (for them) departing the roadway anywhere, anytime. Of course, sometimes broken poles fall on cars or people, power outages are more routine especially after vehicular accidents, and there are other tradeoffs too, some of which are safety-related.
[1] https://safety.fhwa.dot.gov/roadway_dept/countermeasures/saf...
Nice questions. But it doesn't give them right to build a concrete obstacle for lights, when it is possible to make it without hard obstacle.
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.
Compared to that mall collapse, a berm that far off the end of the runway won’t even be notable.
Oh I'm fully aware, I take no issue with her ire, just didn't expect that answer, tho I should have. To her point, the South of South Korea, especially in the country area, has loads of stuff like this, there are disasters waiting to happen everywhere, much of the infrastructure should be gone through with a fine tooth comb really, like this still both boggles my mind and boils my blood: https://www.reuters.com/world/asia-pacific/fire-south-korean...
They used a HIGHLY flammable material to completely cover a raised highway.
(All of that said, I read from so many people now that the plane would have disintegrated once it did finally start to drag given the speed, and there is another parameter wall shortly after the berm.)
They used a HIGHLY flammable material to completely cover a raised highway.
(All of that said, I read from so many people now that the plane would have disintegrated once it did finally start to drag given the speed, and there is another parameter wall shortly after the berm.)
Safety hazards and disregard for accesibility as well
[deleted]
carabiner(3)
iso8859-1(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.
They already botched a gear down landing, which is almost never mentioned. They retracted the gear and did a teardrop go around from a headwind into a tailwind belly flop.
Stinks of bad crew resource management and ATC which is why the ATC and airline for raided by SK officials.
Stinks of bad crew resource management and ATC which is why the ATC and airline for raided by SK officials.
We don’t know why the pilot elected to double back instead of go around. There may have been indications of a progressive failure that indicated that course of action, but it does seem hasty. That haste may have caused them to not be able to set up a stabilized, minimum speed approach, and may have contributed to the long touchdown, which certainly was a contributing factor.
If there were significant winds it would have compounded those factors.
It is curious that the gear was retracted. I can only think that this was due to some kind of system failure? Perhaps that same failure explains the decision to double back instead of going around?
Lots of questions, hopefully there will be answers.
Still, the structure does not seem to meet the standard for frangibility that is indicated for objects in the approach path within 300m, although it’s not like it was at the very end of the runway.
Runway over/undershoots are actually quite common, and the building of a nonfrangible structure on an otherwise safe skid zone is a significant error in design principles that is not common or conformal to industry standards.
If those antennas had been placed on property designed towers instead of a concrete bunker, the passengers and crew very well may have walked away without a scratch, despite any errors on the part of the crew or procedures of the airline.
If there were significant winds it would have compounded those factors.
It is curious that the gear was retracted. I can only think that this was due to some kind of system failure? Perhaps that same failure explains the decision to double back instead of going around?
Lots of questions, hopefully there will be answers.
Still, the structure does not seem to meet the standard for frangibility that is indicated for objects in the approach path within 300m, although it’s not like it was at the very end of the runway.
Runway over/undershoots are actually quite common, and the building of a nonfrangible structure on an otherwise safe skid zone is a significant error in design principles that is not common or conformal to industry standards.
If those antennas had been placed on property designed towers instead of a concrete bunker, the passengers and crew very well may have walked away without a scratch, despite any errors on the part of the crew or procedures of the airline.
They declared mayday and then were on the ground in like 3 minutes. I think they probably just forgot gear given how rushed the landing was. We'll find out from the investigation.
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/jasonwells/transasia-pi...>
I seem to recall a Mentour Pilot episode (YouTube channel) describing either that or a similar incident.
Point being that when things start going very wrong you've got to actively think to prevent making them worse.
"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/jasonwells/transasia-pi...>
I seem to recall a Mentour Pilot episode (YouTube channel) describing either that or a similar incident.
Point being that when things start going very wrong you've got to actively think to prevent making them worse.
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.
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.
So... the degree of control they have over the plane on landing suggests they have some degree of hydraulic control. It's possible they throttled down the wrong engine, but this is speculation at this time.
Landing gear has a manual gravity release by the first officer that doesn't require the hydraulics. (But does take some time.)
Ground effect was certainly involved (why they glided so far before touching down) but the bigger factor was their high speed, lack of flaps, and lack of gear.
Landing gear has a manual gravity release by the first officer that doesn't require the hydraulics. (But does take some time.)
Ground effect was certainly involved (why they glided so far before touching down) but the bigger factor was their high speed, lack of flaps, and lack of gear.
They retracted the gear after the first landing attempt. I suspect they either missed it on the teardrop or had secondary hydraulic failure and no time to do a gravity drop. I would err on the side of crew error because there were clear signs the hydraulic systems were functioning (thrust reverser and that they could retract the gear in the first place). Hydraulics don’t fail instantly and one engine was spooling still on landing.
That's why EASA says put the plane down if there’s a strike on approach. Ryanair 4102 is a good example of a close one there as a reference.
That's why EASA says put the plane down if there’s a strike on approach. Ryanair 4102 is a good example of a close one there as a reference.
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.
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.
[deleted]
What should ATC have done differently?
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 emergencies especially, pilots call the shots.
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 emergencies especially, pilots call the shots.
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).
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).
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/
Aviate. Navigate. Communicate.
Yeah, especially given the mayday call, ATC is trying to give pilots the information they need, prepare emergency services, and get the fuck out of the way.
Possible comms failure. ATC are responsible for reporting surface wind. It may have lead to a bad decision by the pilots. Go around versus teardrop etc.
Botched how?
Botched by not using the manual gravity gear drop. Maybe they didn't have enough time. But losing a single engine is not necessarily fatal at that flight phase. Most professionals are still questioning why the rush to get it down. If there is some valid reason, aside from accidentally shutting down the other engine, when we do find out the details, maybe the professionals won't call it botched.
Can’t really call it botched until we know the reason…
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.
> 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 on-heading vector component of wind velocity must be added to the airspeed to get the ground speed... whilst this was a contributing factor to the accident, it's not something to focus on.
There will be a thorough investigation but it will take some time to get answers.
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 on-heading vector component of wind velocity must be added to the airspeed to get the ground speed... whilst this was a contributing factor to the accident, it's not something to focus on.
There will be a thorough investigation but it will take some time to get answers.
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.
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.
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.
Ok but in an emergency all bets are off, the opposite direction is better than a crash landing. So you can't just assume 100% of landings are in one direction.
> Ok but in an emergency all bets are off, the opposite direction is better than a crash landing.
Sure, but so is a highway, or a river. Doesn't mean those should be built to runway standards.
Sure, but so is a highway, or a river. Doesn't mean those should be built to runway standards.
Ok but this is a runway. It should be built to runway standards!
Who doesn't love a good runway: https://youtu.be/1_MO5Wfomks?t=146
It's a runway in one direction only. It doesn't need to be built to the standards for a runway operating in the opposite direction, because it isn't.
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.
It should perhaps be pointed in news coverage since I equated "opposite direction" with "wrong direction" - hence my scepticisms about the wall.
> if you look on Google maps you can see the runway at Jeju
Do you mean at Muan?
Do you mean at Muan?
Idk about this particular airport but it is nearly universal that runways are used from both ends. The idea is to land into the wind.
We don’t know why the pilot elected to double back instead of go around. There may have been indications of a progressive failure that indicated that course of action, but it does seem hasty. That haste may have caused them to not be able to set up a stabilized, minimum speed approach, and may have contributed to the long touchdown, which certainly was a contributing factor.
Still, a 14 ft high concrete structure within 300M of a runway end is unusual, and does not fit the standard for frangable structures which is the guidance for runway aligned equipment.
We don’t know why the pilot elected to double back instead of go around. There may have been indications of a progressive failure that indicated that course of action, but it does seem hasty. That haste may have caused them to not be able to set up a stabilized, minimum speed approach, and may have contributed to the long touchdown, which certainly was a contributing factor.
Still, a 14 ft high concrete structure within 300M of a runway end is unusual, and does not fit the standard for frangable structures which is the guidance for runway aligned equipment.
[deleted]
Even if the runway was only used from one direction (not true), it would be dumb to build a big concrete structure near its beginning. It's not unheard of for planes to come in too low and touch down before start of the runway due to pilot error (or even double engine failure on rare occasions).
Was the runway designed to only be used one way or was this just the it opposite direction of how it was being used at that moment? I understand that at least some airports change the direction based on wind.
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 proximate downtowns with tall towers. Nominal approach glide paths cut below the rooflines of several structures, and make for some interesting experiences for arriving travellers.
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 proximate downtowns with tall towers. Nominal approach glide paths cut below the rooflines of several structures, and make for some interesting experiences for arriving travellers.
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.
What’s noteworthy, there’s a note to use extreme caution due to this wall if landing or taking off towards it.
Strangely, the only snapshots on the internet archive are on Dec 29 2024 (date of the accident) and the day after...
https://web.archive.org/web/20241215000000*/https://aim.koca...
Are we expected to believe these pages never got crawled before?
Can we learn a forensic lesson for this and automatically snapshot similar pages for all runways worldwide?
https://web.archive.org/web/20241215000000*/https://aim.koca...
Are we expected to believe these pages never got crawled before?
Can we learn a forensic lesson for this and automatically snapshot similar pages for all runways worldwide?
FYI, the 01 and 19 names are short for 10 and 190 degrees -- so it's always going to be the case that the opposite runway direction is 18 mod 36 from the other direction.
I don't see that note. There's one "extreme caution" note but it's about some other obstacle 2.1NM from the threshold of runway 1.
> 1.3 Pilot shall use extreme caution during carrying out final approach into RWY 01 or missed approach or departure for RWY 19 due to obstacle located east of extended RWY at approximately 2.1 NM from threshold of RWY 01.
it seems this is the same structure:
https://en.wikipedia.org/wiki/Jeju_Air_Flight_2216#Non-stand...
it seems this is the same structure:
https://en.wikipedia.org/wiki/Jeju_Air_Flight_2216#Non-stand...
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?
3800 - 2800 = 1km.
Did the plane skid for 1km before crashing into the obstacle?
Because the system is bureaucratic and stupid. Notices warning pilots about irrelevant obstacles are, literally, a meme. Example: https://www.reddit.com/r/flying/comments/wzsvru/the_notam_sy...
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.
> 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.
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.
[deleted]
[deleted]
[deleted]
Ate Chuet made a quick analysis about the crash: https://youtu.be/xUllPqirRTI. The wall is there because that area is regularly flooded, it serves for the ILS system, and it is unfortunately over the minimum legal distance for such an object.
It doesn't make sense, though, that it would have to be concrete-reinforced above ground, and non-frangible, just because the area floods.
Maybe it's the cheapest way to engineer the ILS localizer to be flood-resistant? I don't know.
Maybe it's the cheapest way to engineer the ILS localizer to be flood-resistant? I don't know.
Feels like a “pieces of flair” issue.
The runway should be as long as it’s required to be. If after (and before) the paved runway they need a length of open space, that should be however long it is required to be, too. Beyond that there could be a minefield, a pillow warehouse, an ocean, a mountain, etc. It shouldn’t matter.
The runway should be as long as it’s required to be. If after (and before) the paved runway they need a length of open space, that should be however long it is required to be, too. Beyond that there could be a minefield, a pillow warehouse, an ocean, a mountain, etc. It shouldn’t matter.
After the arrestorbed will be a massive magnetic sled that will accelerate to the speed of the plane and then decelerate the whole thing!
Only infinity billions of dollars for each airport and likely cause other issues, but, progress!
Only infinity billions of dollars for each airport and likely cause other issues, but, progress!
Just a message thinking for anyone reading who might have had some relative in this plane: sincere condolences.
A plane usually crashes because of multiple reasons. The fact that runway design was one of them is a big deal because it was a concern for all airplanes landing there not just one of them.
This is probably only the tenth or eleventh most-important question to answer about why this disaster happened, unfortunately.
The wall is a red herring 2. why was a commercial airliner attempting a no-gear belly landing with full fuel load on a runway that's only 2,800m, rather than divert to Incheon?
The title question is like the 20th in order of importance why this crash happened…
[deleted]
Cause of death was impacting a concrete barrier.
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 power that could have been used to stay aloft and sort out their problems.
Nothing about this crash was normal, and talking about a thing past the end of the runway is misdirection.
Nothing about this crash was normal, and talking about a thing past the end of the runway is misdirection.
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.
Engine losses due to bird strike are pretty common. Planes declare an emergency and are vectored to a holding pattern where they run though emergency checklists and verify that they are ok to land at the current airport with current capabilities, weight, weather, etc. This takes 10 to 20 minutes.
This did not happen on this flight
This did not happen on this flight
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.
I don't know what happened in this event, but the concrete box is painfully uninteresting compared to basically anything that happened before it.
They had gear down, got a bird strike, did a go around, and retracted gear. At that point everything is fine and by the book but what happened next is the question - and why.
Either they would have actually "gone around" and executed the original approach (which would have been aborted when the gear didn't lock), or they had had mechanical problems and wouldn't have been able to make this 180º turn if they wanted to. There was ocean on three sides of them that would have provided a rough but survivable landing, as demonstrated a decade ago in New York.
At no point was this landing fine or by the book, and talking about ground obstructions is just a way to distract you.
At no point was this landing fine or by the book, and talking about ground obstructions is just a way to distract you.
If we go back far enough the fatal error is the Wright brothers inventing the airplane.
It might be more useful to start with the solid concrete plane stopper and work backwards than work forwards from 1903.
It might be more useful to start with the solid concrete plane stopper and work backwards than work forwards from 1903.
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_.
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.
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.
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?
I've watched nearly all the "Aviation Disasters" episodes. I don't recall any footage other than incidental amateur footage. The investigators spend a lot of time even figuring out where on the runway the various planes were, implying there was no footage.
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.
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.
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.
> At a news conference on Tuesday, Jeju Air's chief executive Kim Yi-bae would not be drawn when asked about the concrete wall.
I don't understand what means "would not be drawn"?
> Asked by a reporter if he thought the wall was a factor in the disaster, he did not give a direct answer and instead said it was right to call the plane crash the Jeju Air disaster, rather than the Muan Air disaster.
If I get this right, I think this CEO deserves props for not trying to point blame away. Let's see what investigation shows.
I don't understand what means "would not be drawn"?
> Asked by a reporter if he thought the wall was a factor in the disaster, he did not give a direct answer and instead said it was right to call the plane crash the Jeju Air disaster, rather than the Muan Air disaster.
If I get this right, I think this CEO deserves props for not trying to point blame away. Let's see what investigation shows.
> Firefighters said some bodies were scattered 100 to 200 m (330 to 660 ft) from the crash site while others were found mutilated or burnt among the wreckage.[61] Police officials said it would require over a week to identify the more than 600 human remains recovered.[62] Some family members provided officials with DNA samples at the airport to help identify the dead.[4] (Wikipedia)
Does this mean the crash was so violent that the 179 bodies disintegrated into more than 600 parts?
Does this mean the crash was so violent that the 179 bodies disintegrated into more than 600 parts?
The plane hit a concrete wall at something like 150 knots, so it was pretty violent.
Korean police have raided the airport offices
https://youtu.be/3D9BDIH553U
https://youtu.be/3D9BDIH553U
I was wondering what if they tried to turn whether by rudder or thrust differential would the outcome have been different/worse. Maybe you can't do much at that speed and so little room.
I'm a pilot. The airplane was sliding on the ground and the landing gear was not deployed. Too fast to stop but not fast enough to use the rudder for directional control. There was no realistic chance to change direction.
If there had been enough engine power to control direction on the ground, there might also have been enough power to remain airborne, but based on limited information, that wasn't so. Under the circumstances the pilots would have wanted to stay airborne to buy time for a more controlled descent, were that possible.
All these speculations are preliminary and may completely change once the black box information is released.
If there had been enough engine power to control direction on the ground, there might also have been enough power to remain airborne, but based on limited information, that wasn't so. Under the circumstances the pilots would have wanted to stay airborne to buy time for a more controlled descent, were that possible.
All these speculations are preliminary and may completely change once the black box information is released.
> not fast enough to use the rudder for directional control.
Sure about that? 160kt (how fast someone calculated it went off the end of the runway) is way above Vs1 for a 737, there should be plenty of rudder authority. Heck, Vapp is usually in the 130-150kt range.
Sure about that? 160kt (how fast someone calculated it went off the end of the runway) is way above Vs1 for a 737, there should be plenty of rudder authority. Heck, Vapp is usually in the 130-150kt range.
Rudder authority in the air, but scraping on the ground you’re not going to change direction - or take-off, either.
If they were trying to take off again, there wasn’t any hope.
If they were trying to take off again, there wasn’t any hope.
[deleted]
I don’t know why people keep fixating on this. Airplanes can’t skid out of the airport into the surrounding city. Mistakes were made, but this isn’t one of them. I suspect it is people trying to deflect blame from pilot error, which seems by far the most likely issue. They did none of the things you should do to stop a plane.
There is nothing beyond the embankment. Airports are generally made in the middle of nowhere. And no, they are not "skidding" into the surrounding city, he probably needed a few hundred meters at most.
He’s going extremely fast, a few hundred meters would do nothing. I think the estimates I saw were over 150 knots. That’s about 77 meters per second.
I found this comment helpful from a Reddit thread.
>The embankment is there to protect the road from the jetblast of departing aircraft in oposite runway direction. Thats why it is allowed directly in the safety area.
I found this comment helpful from a Reddit thread.
>The embankment is there to protect the road from the jetblast of departing aircraft in oposite runway direction. Thats why it is allowed directly in the safety area.
> a few hundred meters would do nothing. I think the estimates I saw were over 150 knots
Show you working. Not feelings because people don't have intuition for such unusual motion. You could equally have said "a few hundred meters would be enough."
Show you working. Not feelings because people don't have intuition for such unusual motion. You could equally have said "a few hundred meters would be enough."
150 knots is like 77 meters a second, a 747 can do like 2m/s^2 braking giving 35 seconds to stop, 1500 meters required.
Stopping time: t=v/a, t=77/2. Stopping distance: d=v^2/2a, d=77^2/2*2
Stopping time: t=v/a, t=77/2. Stopping distance: d=v^2/2a, d=77^2/2*2
Now account for the fact that the plane had no brakes since the landing gear were not deployed ...
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!
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
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
Thanks for the link. Nowhere it seems to indicate that the friction of the breaking would be greater than the friction of the hull, since the pages related to non-destructive braking.
Airplanes use disc brakes. These can provide pretty much unlimited friction and are very destructive to the brake pads. They are effectively limited by the static friction of the tire and how much waste heat they can dissipate without blowing the tire.
Look it feels like you want to win an argument. You can only win it for people who do not understand the difference between static friction of a tire on tarmac and kinetic friction of a hull on tarmac. I couldn't tell you off-hand which has more friction, but I'm ready to believe by example that the hull has bad properties when it comes to braking. It's made for low friction after all.
Look it feels like you want to win an argument. You can only win it for people who do not understand the difference between static friction of a tire on tarmac and kinetic friction of a hull on tarmac. I couldn't tell you off-hand which has more friction, but I'm ready to believe by example that the hull has bad properties when it comes to braking. It's made for low friction after all.
(That's with brakes and flaps.)
Maybe not all completely aligned straight forward with the landing, but it looks like yes there are some inhabited zones over there surrounded by wooded parcels, well before the landscape change for some sea.
https://maps.app.goo.gl/BN15aSQ1pW6vJkzb7
https://maps.app.goo.gl/BN15aSQ1pW6vJkzb7
740m before hitting the next structure.
Like doing what things? What I read so far is that they suspect the pilot had control issues.
I don't think people who say that it's a bad idea to have a concrete wall at the end of the runway argue the plane should make its way to a nearby motorway. I think most refer to using EMAS, ie a crushable concrete floor in which the plane sinks and stops.
I don't think people who say that it's a bad idea to have a concrete wall at the end of the runway argue the plane should make its way to a nearby motorway. I think most refer to using EMAS, ie a crushable concrete floor in which the plane sinks and stops.
EMAS is designed to crush under the pressure of all of the aircraft's weight pushing down on the relatively narrow contact area of the tires. There were no tires in this case. I am unaware of an EMAS that has been designed or tested for the far more broadly distributed weight of a belly landing.
That’s a fair objection. Still you would expect the plane to sink into the grass after that.
> bad idea to have a concrete wall at the end of the runway
but was it the end of the runway? As I understand, the pilot came in from the opposite direction, i.e.
> The pilot then aborted the original landing and requested permission to land from the opposite direction.[1]
So that wall was located at the beginning of the runway if the runway was used correctly.
From the bottom image[2], it would appear the wall is located behind the point where planes begin their take-off (and I assume their landing) - but I'm no aviation expert.
[1]: https://www.bbc.com/news/articles/ckgzprprlyeo [2]: https://ichef.bbci.co.uk/news/1536/cpsprodpb/9090/live/ab9db...
but was it the end of the runway? As I understand, the pilot came in from the opposite direction, i.e.
> The pilot then aborted the original landing and requested permission to land from the opposite direction.[1]
So that wall was located at the beginning of the runway if the runway was used correctly.
From the bottom image[2], it would appear the wall is located behind the point where planes begin their take-off (and I assume their landing) - but I'm no aviation expert.
[1]: https://www.bbc.com/news/articles/ckgzprprlyeo [2]: https://ichef.bbci.co.uk/news/1536/cpsprodpb/9090/live/ab9db...
Looking at the map, there isn't much beyond the runway.
You are probably right on pilot error, dont forget Boeing probably want this to be the story as well!
The 737 is one of the most popular aircraft in the world. It's had hundreds of incidents. There is no reason to think that there is any conspiracy going on, and there is not sufficient information to even think that any Boeing specific details were a factor in the incident.
But it wasn't there for this reason, and if it was, I'm sure they would have had more than 250m of space to put it at the far ends of the airport.
“keep fixating” may just be what’s rising to the surface in your algorithm. My own sense has been that the questions are pretty spread out.
South Korean communities are fixated on this wall issue to an abnormal degree. Discussion of this wall has become a congregation of people who
1. See this tragedy as an opportunity to deride province the airport is located in.
2. Want to be contrarian to those who tell them to wait until official results are out.
3. Feel like the society is "forcing them to mourn" (whatever that means) and would like to look at the cold hard "FACTS".
It's a mess.
[deleted]
How much difference would an additional 50m have made?
50m of runway? Not much difference
50m of arrestor bed? Some difference, probably meaningful.
https://en.wikipedia.org/wiki/Arrestor_bed
50m of arrestor bed? Some difference, probably meaningful.
https://en.wikipedia.org/wiki/Arrestor_bed
Would an EMAS even work for a gear-up aircraft? EMAS is designed to crush under the pressure of the gear. With all of that load distributed the the engines and along the centerline of the fuselage, would the pressure breach the material?
To be brutally honest, the plane would crash about a second later, so approximately none whatsoever.
But this isn’t the right question to ask, as it isn’t the right question to ask why the wall was there. Why did the pilot and ATC decide it’s a good idea to attempt a gear up landing in the wrong direction is a good start.
But this isn’t the right question to ask, as it isn’t the right question to ask why the wall was there. Why did the pilot and ATC decide it’s a good idea to attempt a gear up landing in the wrong direction is a good start.
I recall back in 2020, when Pakistan International flight 8303 belly landed at Karachi, slid down the runway, and then took off again and had a go at going around, the investigation showed that between them, the pilots just screwed up on having the landing gear down and had a go at landing without it for no other reason than they fumbled it.
The PIA pilots totally fucked up the approach, missed that they were very high late in the approach, dive bombed down to the runway at the last minute instead of going around. CRM issues -- the senior pilot plausibly couldn't actually fly (he had a history of bad approaches with unsafe descents) and the first officer failed to raise major problems or push back at all on unsafe decisions. When they first touched down gear up, they had dual stick inputs (one pilot was pushing down, one was pulling up) -- this is a huge no no. Communication in the cockpit was awful. Just lots of awful.
After the incident, PIA pilots were audited and determined like 1/3 had fake or suspicious pilot licenses(!!!). Lots of paying other people to pass tests for you. Internationally, PIA has been banned from landing by like all first world countries.
After the incident, PIA pilots were audited and determined like 1/3 had fake or suspicious pilot licenses(!!!). Lots of paying other people to pass tests for you. Internationally, PIA has been banned from landing by like all first world countries.
Compared to running into a concrete wall probably a lot
They'd probably have another 1000m of relatively clear ground without the localizer mound. The brick fence probably wouldn't significantly slow the aircraft, then you have a relatively clear easement (with ILS approach towers, hopefully frangible) until a parking lot and trees on the south coast.
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.
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.
[deleted]
"... 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 of the runway."
I mean that was a pretty obvious design flaw that went against common standards. I agree it isn't cut and dry yet but an investigation isn't going to change the above info.
"...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 of the runway."
I mean that was a pretty obvious design flaw that went against common standards. I agree it isn't cut and dry yet but an investigation isn't going to change the above info.
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).
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).
I don’t disagree with that. It is a compounding issue but I am much more interested in what happened up to that point. Many many small things or one big thing went wrong for it to even get to that point.
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.
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.
Absolutely correct! Had the bird strike not occurred, there wouldn’t have been a crash. Had things with the go around been handled properly, there would have been no crash.
Etc etc. The fact that a wall was 50m out of compliance or whatever it ends up being will be a footnote at best in the review of this crash.
Etc etc. The fact that a wall was 50m out of compliance or whatever it ends up being will be a footnote at best in the review of this crash.
There's a few more you're missing there which is the point of the investigation.
Even with all of the compounded problems, the flight could have been non fatal in most world airports.
I wouldn’t state that with any certainty. They touched down 1500m down the runway with little to no braking or reverse thrust. The ending may have been less violent but the outcome may have been the same. I’d rather go from blunt force than being burned alive if a wing ditched and it rolled.
Let’s wait for the investigators. It’s not good to fixate on this outcome.
Let’s wait for the investigators. It’s not good to fixate on this outcome.
This is the landing of United Airlines Flight 232 in Sioux City, Iowa in 1989. It hit the runway very hard, tumbled, broke, left the runway, and burned, but encountered no significant non-frangible obstacle. Of 296 passengers and crew on board, 184 (62%) survived. It is reasonable to assume that given the absence of other significant non-frangible obstacles beyond the ILS mound that loss of life would have been low and potentially zero.
https://youtu.be/sWkU6HRcOY0
https://youtu.be/sWkU6HRcOY0
Your comments on this page offer many opinions sans investigation or facts.
Why is it always Boeing?
I have been to airports whose runway end in the ocean, a swamp, a mountain and a 5 lane highway.
I’m worried about the ocean all the time, so it’s weird to think that’s actually the best kind of scenario.
Well depends on the weather conditions. All the successful plane ditches happened when there weren't any waves.
It wouldn't be a ditch anymore. The plane won't be going perfectly straight and level while hitting the water, so there's a pretty good chance one wing/engine would hit the surface first and cause a cartwheel.
Runway’s gotta end somewhere
Technically it could loop around the earth.
You don’t even have to make it that long, you can just make a large circle of runway:
https://en.wikipedia.org/wiki/Endless_runway
https://en.wikipedia.org/wiki/Endless_runway
[deleted]
So many things went wrong, and yet the pilots brought the plane down safely – and then this!? Just infuriating.
Bringing a plane down safely involves doing it in a way that lets you come to a stop before you crash into something that’s going to kill everyone. You don’t get points for touching a runway at a point where there isn’t enough of it left for you.
No commentary on the pilots’ role here, we don’t know nearly enough to judge. Could be they did a great job and they were just doomed. But the end result is that they didn’t get it down safely.
No commentary on the pilots’ role here, we don’t know nearly enough to judge. Could be they did a great job and they were just doomed. But the end result is that they didn’t get it down safely.
Absolutely no. There is the suspicion that they even shut down the good engine after the bird strike.
> Absolutely
> suspicion
"suspicion" seems like fragile grounds for "Absolutely".
> suspicion
"suspicion" seems like fragile grounds for "Absolutely".
It objectively wasn't a safe landing. How that happened is anyone's guess, until the investigation comes out.
Those are 2 sentences.
Lately I’ve seen lots of people doing such snarky comments, without reading carefully, or just writing things that are absolutely illogical… what is going on?!
Lately I’ve seen lots of people doing such snarky comments, without reading carefully, or just writing things that are absolutely illogical… what is going on?!
> Those are 2 sentences.
Are you saying the two sentences, in sequence, are unrelated?
> snarky
I wasn't intending to be snarky. My point was serious: 'suspicion' is not grounds for 'absolutely'.
Are you saying the two sentences, in sequence, are unrelated?
> snarky
I wasn't intending to be snarky. My point was serious: 'suspicion' is not grounds for 'absolutely'.
[deleted]
They did not bring the plane down safely! The pilot failed to lower the landing gear, or extend the flaps, both of which, for all intensive purposes were technologically possible. Multiple redundant systems for these. I think they completely lost situational awareness, and panicked.
>for all intensive purposes
Always a funny one, it's for all intents and purposes
Always a funny one, it's for all intents and purposes
When an engine blows up, it’s hard to say what still worked and what didn’t. They aren’t supposed to, but when turbines come apart, there is often a lot of shrapnel that has a history of taking out multiple systems.
But, it is possible that it was a case of poor crew performance.
In any case, the concrete blockhouse at the end of the runway was unhelpful, and it is also outside of the standard guidance for runway aligned obstructions. In most cases, those antennas would have been on frangible towers, and the crew, at fault or not, as well as the passengers, would have had a decent chance of walking away unharmed.
But, it is possible that it was a case of poor crew performance.
In any case, the concrete blockhouse at the end of the runway was unhelpful, and it is also outside of the standard guidance for runway aligned obstructions. In most cases, those antennas would have been on frangible towers, and the crew, at fault or not, as well as the passengers, would have had a decent chance of walking away unharmed.
There are 3 different hydraulic system plus one electric that can be operated out of a battery… anything is possible, but it seems until now they failed to lower the gear.
Something else that may be a factor, a lot of Asian carriers teach their pilots to use auto pilot for landing. American pilots almost universally SOP do not use auto pilot when landing. It's possible the South Korean pilot was using auto pilot to land, forced to do a go around, but wasn't in the habit of manually configuring the plane for landing. That's how the flaps and the gear were both missed. He assumed autopilot etc was handling that.
I think in the cockpit voice recording we are going to be hearing the sirens going off about no landing gear and those guys were just not paying attention.
I think in the cockpit voice recording we are going to be hearing the sirens going off about no landing gear and those guys were just not paying attention.
That would be a tragic void in training and procedure. I hope for the sake of the families involved that it doesn’t turn out to be something so avoidable in practice and foreseeable in the carriers operating procedure.
There are numerous past examples of this sort of thing. Automation in aviation is really hard to get right. If the automation can fail then the pilots need to be able to perform whatever it was going to do. If the automation fails rarely then the pilots may not get enough practice. But if the automation normally does a better job than the pilots, there’s a tension with letting them get more practice on real flights.
A recent(ish) example is the Asiana crash in SF. They had pretty much perfect conditions for a hand-flown visual approach, but they were out of practice, got behind the airplane, and it snowballed.
There’s an excellent lecture about this called Children of the Magenta Line. The magenta line being the flight path or direction indicator on an autopilot, and the discussion is about pilots who constantly reconfigure the autopilot to direct the plane instead of just taking over. https://youtu.be/5ESJH1NLMLs
A recent(ish) example is the Asiana crash in SF. They had pretty much perfect conditions for a hand-flown visual approach, but they were out of practice, got behind the airplane, and it snowballed.
There’s an excellent lecture about this called Children of the Magenta Line. The magenta line being the flight path or direction indicator on an autopilot, and the discussion is about pilots who constantly reconfigure the autopilot to direct the plane instead of just taking over. https://youtu.be/5ESJH1NLMLs
I’m afraid it will be something like that…
Which aircraft have flaps or gear controlled by an autopilot? I'm just an armchair "Air Crash Investigations" fan, but I've never heard of any aircraft where either flaps and gear would be automatically controlled by their autopilot. Speedbreaks / spoilers are usually armed and moved automatically on landing.
There's also a backup manual gear release. But from the degree of control over the airplane demonstrated during landing, it seems likely they had hydraulics.
They were with gear down, the retracted it, as part of the go around…
We don't know that for sure yet. The gear being down is based on an eyewitness report, as far as I understand from Juan Browne. The readout from the flight data recorder will provide a more trustworthy account.
If I recall right the video that purportedly shows the bird strike shows the gear down.
The bird strike (well, compressor stall) video I saw appears to show gear up.
https://x.com/Global_Mil_Info/status/1873181671375421703
https://x.com/Global_Mil_Info/status/1873181671375421703