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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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