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

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

#151
post #146
post #126

Earlier quoted context omitted.

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

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

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.

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

#152
post #60

Earlier quoted context omitted.

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 circ…

> 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.

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.

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

#153
post #128
post #81

Earlier quoted context omitted.

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.

Ok but this is a runway. It should be built to runway standards!

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

#154
post #46

Earlier quoted context omitted.

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

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

Aviate. Navigate. Communicate.

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

#155

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.

“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.

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

#156

Lots of airports have obstacles not far from the end of the runway. Burbank, Midway, Orange County are a few that come to mind. Why did they need to land when they did? Why did they need to land so soon after the mayday call? (only 8 minutes from mayday to crash, as I understand it) Why couldn't they land on a longer runway? Why did they land so far down the runway? What forced them to land in a clean configuration?…

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

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

#157

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.

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!

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

#158

Earlier quoted context omitted.

> 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

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.

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

#159
post #149

The wall is a red herring. The plane landed halfway down the runway at high speed. Something bad is going to happen if you do that at any runway on earth. In SFO you'll end up in the bay or hit the terminal depending on the orientation. In Toronto you'll crash into a highway. Stop looking at the wall and look at the minutes before the crash.

This exactly. The biggest problem was that it came down with no gear or flaps (as far as I'm aware at least).

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

#160
post #153
post #128

Earlier quoted context omitted.

> 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.

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
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