On December 29, 2024, we saw a Jeju Air Boeing 737-800 crash land in Muan, South Korea, killing 179 of the 181 people onboard. This marked the deadliest crash ever on South Korean soil, and at the time, the deadliest crash globally since 2018 (in the meantime, the Air India Boeing 787-8 crash took over that title).
As you’d expect, aviation accident investigations take some time, and authorities are starting to reveal more findings from their investigation. I first covered this last week, but we now have some more conclusive details, as flagged by Reuters. However, it seems that the union representing pilots, as well as families of the victims, aren’t happy with what’s being shared…
In this post:
Jeju Air Boeing 737 pilots shut down wrong engine
As a reminder of the very basics of this accident, we know that the Jeju Air Boeing 737 suffered a bird strike while on approach to Muan, as that’s what pilots communicated to air traffic controllers. The plane seemed to completely lose power, as the gear couldn’t deploy, and the black box data is even missing for the last four minutes of the flight.
So in that sense, it’s impressive that the plane even managed to land on the runway. What made this so tragic and fatal is that there was a barrier at the end of the runway, which the plane crashed into, and then it caught fire, breaking the plane into two. That’s what contributed to the high fatality count, and the design of the barrier is now under serious scrutiny.
However, what actually happened here? Why did the plane seemingly lose power in both engines? Was this like US Airways flight 1549, which landed in the Hudson River, where the birds took out both engines? Not quite…
South Korea’s Aviation and Railway Accident Investigation Board has determined that there’s evidence that the pilots shut down the less damaged of the two engines 19 seconds after the bird strike. After the bird strike, the right engine had a surge and emitted flames and black smoke.
The cockpit voice recorder, computer data, and physical engine switch found in the wreckage, showed that pilots shut off the left engine instead of the right engine. Not only that, but investigators have determined that the left engine “was confirmed to be generating output sufficient for flight,” meaning that if the incorrect engine hadn’t been shut off, the plane could have maintained power, and likely landed safely.
During the investigation, no defects were found with the aircraft or its engines. Investigators don’t yet know why the pilots turned off the wrong engine.
This wouldn’t be the first time that a fatal accident happened because pilots turned off the wrong engine. In the 1989 Kengworth air disaster, a British Midland Boeing 737-400 crashed when the pilots turned off the wrong engine while on final approach to the airport.
Families & pilots aren’t happy with these findings
Investigators are expected to issue a final report in June 2026, so these findings are only part of a preliminary report. A little over a week ago, their plan was to hold a media briefing with updates about the investigation, but that ended up being canceled, after objections from families and representatives of the pilots union.
Families of the victims were reportedly briefed on the report ahead of its planned release, but objected to the publication, claiming that it appears to blame pilots, without exploring other contributing factors. The families claim the investigation needs to focus on the barrier, which may have contributed to the high death toll. Families also claim that the proposed report used some phrases that could be interpreted as a final conclusion having been reached.
The union representing pilots claims that investigators are “misleading the public” and “silent about organisational responsibility,” emphasizing that bird remains were found in both engines. The union states that investigators are trying to make the pilots the “scapegoats,” by not providing scientific or technological grounds to show that the plane could’ve landed with only the left engine turned on.
So this is a tricky situation, if you ask me:
- I appreciate if investigators want to release an interim report with more details about what they know happened
- That interim report isn’t a final report, so it also doesn’t preclude other factors, like the location of the barrier, which no doubt contributed to the death toll on this flight
- It sounds like investigators are confident that the left engine was working better than the right engine, and that it had enough thrust to allow the plane to continue to operate
One major challenge with aircraft accident investigations is that no matter what, some party (or parties) won’t be happy with the details provided. Sometimes it’s the union representing pilots, sometimes it’s the airline, sometimes it’s the aircraft manufacturer, sometimes it’s the pilots, sometimes it’s the government.
As much as technology has improved, it often feels like we’re regressing when it comes to learning from aircraft accidents. For example, China is refusing to reveal the cause of the deadly March 2022 Boeing 737 crash on “national security and social stability” grounds.
Furthermore, it also feels like the percentage of accidents where pilot error is a major contributing factor is increasing drastically over time. Perhaps that’s a testament to how well built planes are, and that aircraft issues as such are rarely the root cause of accidents. Ultimately aviation is (at least broadly) as safe as it has ever been, and humans can’t be programmed like computers can.
Bottom line
Investigators in South Korea have determined that the pilots of the Jeju Air Boeing 737 that crashed in late 2024 shut down the left engine following a bird strike, even though it was the engine that was working better. Investigators believe that the engine that was shut down would’ve had sufficient thrust to continue to power the aircraft, preventing this disaster.
While this definitely isn’t the only cause of the high death count, it certainly seems like a contributing factor, especially if the engine would’ve prevented the plane from losing power.
Both the union representing pilots and the families of victims are objecting to the release of these findings, believing that there were more structural issues that caused this. So it seems that for now, investigators won’t release their reports, at least officially. However, the report has been leaked to some media outlets.
What do you make of this Jeju Air Boeing 737 crash update?
All the more reason we need cockpit video recorders as part of the black box data recording
British placenames confuse again - it's Kegworth !
I am still mystified by why the aircraft was going so fast along the runway.
I get that they could not operate the flaps.
Was it not possible to cut off power from the one-still-on (damaged) engine,?
Or were they trying to do a go-around?
Airline pilot instructor here. First world aircraft, "third world" flight training. "CRM? We don't need no stinkin' CRM!" Korea is a great country with very smart and capable pilots. I heard that Korean Airlines was dropped from an US carrier alliance because of their overall poor training record for pilots and flight attendants. However, they got their act together and were warmly welcomed back into the fold. Subsequently, they are one of the finest airlines...
Airline pilot instructor here. First world aircraft, "third world" flight training. "CRM? We don't need no stinkin' CRM!" Korea is a great country with very smart and capable pilots. I heard that Korean Airlines was dropped from an US carrier alliance because of their overall poor training record for pilots and flight attendants. However, they got their act together and were warmly welcomed back into the fold. Subsequently, they are one of the finest airlines in the world. In an emergency, the FIRST THING is AVIATE, navigate, communicate. SLOW YOURSELF DOWN. The plane will fly just fine on one engine. Remember the old IBM saying, "THIMk"? Do the QRH memory items, transfer control as necessary, pull out the QRH and METHODICALLY go over each item. When you start "flippin' switches" without confirmation... "SOM TING WONG" "HO LEE FUKE" "BANG DING OUW"
Sadly the people are still dead, regardless the cause. The goal is for this not to happen again. Hence the investigation.
In my country the military tries to benefit from hard lessons learned. This typically translates into a "tick in the box" type of training session. Over time the number of these short training sessions that are based on tragic events in the past increases, and it sometimes feels tedious to spend weeks before...
Sadly the people are still dead, regardless the cause. The goal is for this not to happen again. Hence the investigation.
In my country the military tries to benefit from hard lessons learned. This typically translates into a "tick in the box" type of training session. Over time the number of these short training sessions that are based on tragic events in the past increases, and it sometimes feels tedious to spend weeks before going on a deployment learning how not to die and getting the "tick in the box" that proves you got the warning/training. One example is people got blown up wandering into minefields in Bosnia and Cambodia. The military developed a half day session where you went into a field with buried mines (dummies) and tried to extract yourself by crawling out inch by inch with a bayonet.
In aviation every crash provides some lessons/minefields to be learned. Imparting the hard earned knowledge will likely translate to more simulator time for pilots. This is the cost of doing business. Checking that the correct engine is shut off in an emergency if not already in the syllabus may become the next "tick in the box" item in the simulator. Or maybe it is something else. The investigation may lead to another conclusion.
It its what it its if you look decades back of planes crashes the majority are pilot error.
It stems from Korea's hierarchical culture where subordinates simply do not challenge someone more senior than they are. They fear dishonoring someone more senior than them than death itself.
Just remember the Asiana Boeing 777 that hit the seawall in SFO! Three pilots let that plane go into a wall because no one would speak up! The ONLY funny thing in that whole tragic event was a major new TV news channel announcing the names of the pilots without verification: Som Ting Wong, Ho Lee Fuke and Bang Ding Ouw
"Three pilots let that plane go into a wall because no one would speak up!"
Worse. The jr. pilot told the captain flying THREE TIMES to watch his sink rate, and asked TWICE if they should go around.... and was ignored on all 5 points.
Wasn't that jr. pilot named Wee Tu Low?
South Korea is just like China. Same attitude. Pretty much Korea has always been just a provence of China.
How many more lives need to be lost before we remove the single leading contribution to fatal accidents.
So you want to scrap all Boeing planes? ALL of them?! mmmkay....call us when you're done.
…. a good response John.
Eskimo has consistently failed to prove his case for such actions. He has been asked if his “machines” could have saved the Hudson River passengers and crew, however, no tangible evidence has been provided.
I read some info that below some certain altitude, there should be no turning an engine off quickly until the situation is totally clear. In fact, isn't the engine constantly trying to restart itself anyway; why would there be a need to turn it off unless fuel is streaming out and causing a fire hazard.
And on a different point, fed up with the "rights" of any pilot or other party to take precedence over accurately finding out and publishing what happened.
It's always baffled me as to why the US allows pilot union representatives to be part of these investigations. Even suck things like not publicly releasing CVR tapes is the result of these unions. They should be nowhere these investigations. They're welcome to refute the findings after the conclusion but should NOT have the ability to steer the course.
The 737-800NG does not have auto relight. AVIATE, navigate, communicate. You FOLLOW THE MEMORY ITEMS AND THE QRH.
Also in 2015, the pilot flying of an ATR72-600 turned off wrong engine when the other was autofethered soon after takeoff, the ATR crashed into a river next to an elevated expressway in Taipei, Taiwan.
So regardless of anything that happened why the South Koreans chose to put essentially a massive concrete wall at the end of the runway is insane. If water or something else is on the other side of that barrier whats better..hitting a barrier with all that mass or sliding into the water. If that barrier had not been present many lives that were lost would be around today.
"If that barrier had not been present many lives that were lost would be around today."
It never works that way with aviation accidents. Multiple factors in error have to align. Could just as easily say "if pilots hadn't shut down a functional engine, many lives that were lost would be around today."
Both had to be present, in order for this tragedy to play out.
Reuters says the damaged right engine still had enough thrust to keep the plane aloft. Read the article again.
I’m honestly not sure if that would’ve prevented the crash because they still would’ve had to land without landing gears and there’s a reasonable chance that they still would’ve crashed into the barrier. Perhaps marginally more lives could’ve been saved but this evidence is obviously not a smoking gun - notwithstanding that the interim report isn’t supposed to apportion blame on any party.
@ Orus -- If the plane had engine power, the landing could've presumably been planned out a bit more, and the plane could've even potentially landed at an airport more suitable for a belly landing. That's only one of the factors, as the plane could have also circled to burn more fuel, reducing the potential fire risk. Also, we don't know for sure what caused the hydraulics failure, right? One theory is that the bird...
@ Orus -- If the plane had engine power, the landing could've presumably been planned out a bit more, and the plane could've even potentially landed at an airport more suitable for a belly landing. That's only one of the factors, as the plane could have also circled to burn more fuel, reducing the potential fire risk. Also, we don't know for sure what caused the hydraulics failure, right? One theory is that the bird strike damaged systems, but it's also possible that no engine power caused it, no?
Ben: It will have to come out in the final investigation but if one ASSUMES that the pilots receive a fire warning, it is possible that he pulled the fire handle BEFORE verifying everything. When the fire handle is pulled it shuts off fuel, trips the generators offline and shuts off the hydraulic system...eliminate the "fuel" to the fire. Once pulled...that's it. If they then twist the fire handle, it will trigger ONE fire bottle....
Ben: It will have to come out in the final investigation but if one ASSUMES that the pilots receive a fire warning, it is possible that he pulled the fire handle BEFORE verifying everything. When the fire handle is pulled it shuts off fuel, trips the generators offline and shuts off the hydraulic system...eliminate the "fuel" to the fire. Once pulled...that's it. If they then twist the fire handle, it will trigger ONE fire bottle. Twist the other way, fires the second bottle. That engine is effectively "toast". Turning the fuel cutoff switch does basically the same thing in sequence but does not arm the fire bottles. The fuel cutoff switches are designed to be hard to pull (heavy spring) and is "notched" to fall into the RUN position. The 737 doesn't have main landing gear doors and thus the gear is held up by a "hook". The nose gear is also held up by a hook and has sufficient weight to push the nose gear doors open when the alternate gear extension handles are pulled. I haven't taught the NG, only the classic so I'm not sure of an alternate flap system like the 777 (which I have taught). The whole tragedy smacks of poor pilot training, recurrent training and lack of CRM!
737 Pilot here. I fly the -800 model. From what I've seen and read:
- The crew probably rushed and made a panicked reaction to shut off an engine. The engines and mounts are designed so they can vibrate and/or burn themselves off the wing if a pilot does nothing. And even if one is only producing 35% power - not enough to sustain flight alone - that's still providing some system redundancy and reducing...
737 Pilot here. I fly the -800 model. From what I've seen and read:
- The crew probably rushed and made a panicked reaction to shut off an engine. The engines and mounts are designed so they can vibrate and/or burn themselves off the wing if a pilot does nothing. And even if one is only producing 35% power - not enough to sustain flight alone - that's still providing some system redundancy and reducing the asymmetry that comes with single-engine flight. Often doing nothing - at least as the initial reaction to an emergency - is the best thing to do. Take a breath, slow down, stabilize the aircraft, assess what's going on, and take your time, before initiating any procedure - even the "memory items". Even if there was a severe engine failure right at rotation (takeoff), nothing is done until climbing through 800'. And that can take a full minute or more, at max takeoff weight, on a single engine.
- The backup procedure to lower the gear without hydraulic power takes some time to do, dropping one at a time via pull handles in the floor behind the center console. But if the crew had not shut off their best engine, they could have had plenty of time to circle, complete the first checklist (Severe Engine Damage) and set up for a reduced flaps landing - and the gear would have come down normally. Even if they had to lower it manually, they could have by following that checklist too. This bird strike should have resulted in a flaps 15, single engine landing you probably would have never heard about, instead of 179 fatalities.
- If the cement barrier (for the ILS mount) was not at the airport, I believe this would still have been a high-fatality accident the way the crew reacted to it. Look at a satellite view of the airport, or Street View the very end of Cheongun-Ro (road) on the south end of the airport. The aircraft was traveling at a very high rate of speed. The ILS antenna (if ground mounted) would have still torn through the aircraft and wings, likely initiating a fire. Then, the plane would bounce over uneven terrain before hitting the cinder block wall (appears to be 8 feet tall) at the airport perimeter at a very high rate of speed. MAYBE there would be a few more survivors in the tail, but not many, I believe.
The families may not like the report - "pilots' fault." If they can't point at the airport or Boeing, that takes two deep pockets off the table to seek compensation from, unless they can claim inadequate training and go after the airline (which I'll bet they do). But in this case, the facts are the facts.
YUP!!
The landing gear on a Boeing 737 will "free fall" when the QRH is followed and the emergency gear extension handles are pulled. They would not have full flap authority but..