Posted on 01/27/2025 11:07:54 PM PST by nickcarraway
Both engines of the Jeju Air plane that crashed last month contained duck remains, according to a preliminary report on Monday (Jan 27), with authorities still trying to determine what caused the deadliest air disaster on South Korean soil.
The six-page report released by South Korean authorities a month after the crash said both engines of the Boeing 737-800 jet contained DNA from Baikal Teals, a type of migratory duck that flies to South Korea for winter in huge flocks. But the report provided no initial conclusions about what may have caused the plane to land without its landing gear deployed, and why flight data recorders stopped recording in the final four minutes of the flight.
The Jeju Air flight from Bangkok on Dec 29 overshot Muan Airport's runway as it made an emergency belly landing and crashed into an embankment containing navigation equipment, called localisers, killing all but two of the 181 people and crew members on board. "After the crash into the embankment, fire and a partial explosion occurred. Both engines were buried in the embankment's soil mound, and the fore fuselage scattered up to 30-200m from the embankment," the report said, providing some new pictures of the accident site.
(Excerpt) Read more at channelnewsasia.com ...
So, who’s the father?
Daffy or Donald?
Duck!
Seems like something could be designed that wouldn’t interfere with the air intake but would keep the birds out of the engines on these planes. Like the cow catchers on trains.
I have wondered about that for many years
Two problems with that. 1. What is strong enough to stop an impact at up to and over 250 mph? 2. What if that fails and gets sucked into the engine?
The question still need an answer: “Did the Jeju Airline goose the goose?”
What type of DNA was taken off the wall at the end of the runaway?
Musk
In the excitement, they forgot to lower the landing gear.
Questions remain!
https://www.youtube.com/watch?v=RtGreTnmSDk
Apparently the birds struck are not large, at around 15 oz. each, but since they do sometimes fly in large flocks, both engines being disabled becomes very plausible.
Bird blood and feathers were found in both engines.
Lack of backup for a both-engines-failure seems inexplicable to me.
Did the pilots panic, or was there just no time to get the gear and flaps down, manually?
There’s vid of the apparent bird strike, but, the birds can’t be seen. A big question is location and time of the bird strike as seen on the vid. Did the plane begin to go around and then it hit the birds?
Is it possible that if the pilots had realized that berm was at the end of the runway, they could have brought the plane down “harder” to counter the tendency of the plane to “skim” (ground effect cushion) just above the runway? An impact more like the plane headed to Grozny that the Russians shot down... might have been preferable.
Not possible. It would be like trying to block a cannonball, with a screen or similar device that was lightweight and not restrictive to the airflow. And that would be hard enough if the engine wasn’t turning and all we had to worry about was the ram air impact from the speed of the aircraft. But on top of that is the fact that the jet engine is sucking in an enormous volume of air, adding to the force.
“Lack of backup for a both-engines-failure seems inexplicable to me.
Did the pilots panic, or was there just no time to get the gear and flaps down, manually?”
The 737 has triple hydraulics, one each driven by the engines gear box ,plus a electric drive motors for system A & B, the stand by system is electric driven and can draw power from either engine or the APU in the tail. System A & B electric pumps can also tap power from the APU at 1/3 the capacity of the engine driven pumps. The 737 does not have a ram air turbine generator or hydraulic pump. The APU is the third redundancy.
Flaps can only be lowered by hydraulic power from either A or B the stand by only does the rudder and wheels. Landing gear has gravity drop manual emergency deploy but not retraction.
The fact of no flaps or gear and the cut out of the FDR and CVR means they not oonly lost hydraulics they lost electric power as well. This almost certainly means they had a double engine bird strike and when they deployed the fire suppression they lost not only electric power,hydraulics but also any relight capacity. Given the lack of apparent back up hydro or electric ppeer they didn’t get the APU up and running. It was reported Th st this aircraft was allowed to take off with it’s APU out of service and granted a flight waver for it until it coild be repaired. So with a double bird strike and two down engines they were dead stick on manual reversion flight controls to only the elevators and alierons the rudder cannot be moved by human forces in the pedals it’s like 500+ lbs each. It was bad luck to get both engines off line and a bunk APU they would have been in deep kimchi.
Its not uncommon for ILS antennas to be elevated on mounds to get the pattern of radiation right. They must also be in line with the centerline. It is expected that aircraft will not over run the over run zone at 150+ knots. It was not a design flaw of the airport many have the same setup due to soil conditions.
In short this flight was doomed as soon as it lost both engines and didn’t have a functional APU. The rules should be changed to no APU no fly or you have to upgrade to having a ram air turbine generator as a fourth level of back up. So at all times even with a bad APU you have triple redundancy.
Gear can be dropped manually with ZERO hydraulic pressure. The gear will fall and lock into place. Same with flaps, but those will take more time to deploy.
Would having the gear down have helped? Probably not.
It was not a wall at the end it was the antenna mound for the ILS localizer antennas. They must be exactly on the centerline of the runway , depending on soil conditions you have to elevate them to get the radiation pattern right. This is not an uncommon set up. Addison international has similar antennas and mounds on one side of it’s runway. It is expected that aircraft do not over run the run out area let alone at 150+ knots. That plane was doomed regardless of the mound they would have just hit the next off runway object at a suicidal 140+ knots that’s just not survivable regardless of what you hit head on that plane was coming apart as soon as it left the runway over run area.
On a 737 gear yes they have a manual emergency deploy but not retraction. Flaps no not on a 737-800 flaps can only be deployed by system A or B hydraulics. There is no manual reversion for flaps ,slats or rudder on the 737 those require hydraulic power from one of the three hydraulic systems. Which can be powered by three sources , either engine pump or electrically via either engines generator or via the APU generator. The electric pumps on the 737 are 400hz AC pumps they cannot tap the DC bus. That bus is for emergency flight instruments and to star
T the APU in the event of a dual engine out.
Given that there is bird strike evidence in both engines it is likely they had a dual flame out situation. There was at last one report that said this aircraft was allowed to take off with it’s APU in a non op condition. With a double engine bird strike and no APU they were dead stick , they could have dropped the gear but flaps without the APU is nit happening on a 737 of that vintage.
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