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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.


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It is curious that the gear was retracted.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.


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.


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.


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.)

You have to reach all the way back to do it, difficult to do with all the other shit going on.


Yes.


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.


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.


8ish seconds into https://x.com/sentdefender/status/1873185457288429583 , it looks like the gear is already up.


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.


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).


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.


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.


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

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


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

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


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!


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.


> if you look on Google maps you can see the runway at Jeju

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.


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.


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.


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?


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...


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?


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.




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