South Korean 737-800 Crash

That thing was pretty well packed with 176 passengers and 6 crew members. The 737-800 seats 162 passengers in a 2 class layout. Or 189 passengers in a high density, one class layout.
 
That thing was pretty well packed with 176 passengers and 6 crew members. The 737-800 seats 162 passengers in a 2 class layout. Or 189 passengers in a high density, one class layout.
I have flown Garuda like that - front bulkhead and rear bulkhead
 
I'm not an airliner mechanic. I do have some comments to delve into ...

- With the engine malfunction (explosion?) just before landing, would that not possibly cause the hydraulics to fail, and therefore be the reason the landing gear was not down?

- Assuming the aircraft was designed to have three functioning means of stopping upon landing (two engines for reverse thrust and functioning brakes on landing gear), then the plane in this situation only had 1/3 of it's normally available equipment to stop upon touchdown. I'm not staying there is an equal amount of force from brakes vs engines, but the reality is that with no brakes and only 1 engine potentially capable of reverse thrust, that plane had no hope of stopping in time to avoid the berm.

- I'm sure the large berm at the end of the runway did its job; presumably to stop aircraft from proceeding downrange and doing more damage. This seems like perhaps more run-off room should be allotted; that would depend upon displacement of whatever is downrange (homes; businesses; etc). I've always been concerned about this at most any airport ... seems like the run-off area is insufficient when bad things happen in combination.
 
Just plain sad, same with the e190 Russia shot down a few days ago. Can't imagine how their families feel especially when they were likely traveling to be together for new years. May god bless them all this is a terrible accident. Hope the investigation is quick and successful.
 
I can't help but wonder if it had ANY reverse thrust available? Considering how the bottom of both engines had become skid pads, supporting the weight of the entire aircraft as it skidded down the runway.... Until there was none left.
 
I'm not an airliner mechanic. I do have some comments to delve into ...

- With the engine malfunction (explosion?) just before landing, would that not possibly cause the hydraulics to fail, and therefore be the reason the landing gear was not down?

- Assuming the aircraft was designed to have three functioning means of stopping upon landing (two engines for reverse thrust and functioning brakes on landing gear), then the plane in this situation only had 1/3 of it's normally available equipment to stop upon touchdown. I'm not staying there is an equal amount of force from brakes vs engines, but the reality is that with no brakes and only 1 engine potentially capable of reverse thrust, that plane had no hope of stopping in time to avoid the berm.

- I'm sure the large berm at the end of the runway did its job; presumably to stop aircraft from proceeding downrange and doing more damage. This seems like perhaps more run-off room should be allotted; that would depend upon displacement of whatever is downrange (homes; businesses; etc). I've always been concerned about this at most any airport ... seems like the run-off area is insufficient when bad things happen in combination.
So for each of the three questions/comments:

First- the 737NG has 3 hydraulic systems: A, B, and standby. Both A and B have an engine driven pump (A driven by ENG 1 and B by ENG 2) and an electrical pump. Both A and B can provide power to all flight controls, however, only A powers the landing gear deployment. However, there is a mechanical release for the landing gear as well which uses gravity (or aerodynamic drag, for the front gear) to lock into place, and it's not known if this mechanical release was attempted.

Second- the checklist for the 737 is complex, depending on the issues being experienced. In short, in a belly landing, it would be expected to see Flaps 40, with no use of spoilers or thrust reversers unless stopping distance was critical.

Third, the concrete wall that housed that portion of the localizer array would not be acceptable many other places. ICAO standards dictate that NAVAID installations be frangible within the runway safety area. You want to slow the aircraft, not bring it to a screeching halt.

Still lots to discover from this accident. Hopefully the 2 flight attendants that survived can provide some insights.
 
And fourth, was the speed involved during landing, and the amount of runway not used. He came in fast and late. Belly landings should be as slow as possible and as soon as runway is available. He didn't drop until about 2/3 of the runway had went by. Yes, this is all preliminary, and armchair, but that's what I see coming out of it thus far.
 
Divert to another airport with much longer runway ?

Barrier at end of runway surprised me, I was thinking a field of sand would be there.
 
There are A LOT of questions here.
1. He touched down on 2/3 of the runway.
2. I cannot see flaps deployed in the video.
3. The barrier protects a residential area that is there. Why not go to an alternative airport? They had a bird strike in the final. They circled a bit, but apparently, the cabin started to fill with smoke.

To me, it seems that the airport was the only option due to the aircraft's conditions. The runway is 8,202ft long. There is the nearby airport, Gwangju, with two runways, each 9,301ft long.
 
That was a brilliant choice to put it there … 😵‍💫

Sounds like a lot of bad decisions, especially a belly landing going way too fast and touching down about 5500-6000 feet on a 9200 ft runway. Someone mentioned the localizer array in a reinforced mound at the end of the runway. I found a picture of this at Muan Airport.

beacon-lights-muan.jpg


Someone mentioned it, but yeah I think they're supposed to break up easily if a plane slides into the antennae, like this setup.

201_img1.gif
 
Sounds like a lot of bad decisions, especially a belly landing going way too fast and touching down about 5500-6000 feet on a 9200 ft runway. Someone mentioned the localizer array in a reinforced mound at the end of the runway. I found a picture of this at Muan Airport.

beacon-lights-muan.jpg


Someone mentioned it, but yeah I think they're supposed to break up easily if a plane slides into the antennae, like this setup.

201_img1.gif

According to FL24, 8,200ft:

IMG_4076.webp
 
There are A LOT of questions here.
1. He touched down on 2/3 of the runway.
2. I cannot see flaps deployed in the video.
3. The barrier protects a residential area that is there. Why not go to an alternative airport? They had a bird strike in the final. They circled a bit, but apparently, the cabin started to fill with smoke.

To me, it seems that the airport was the only option due to the aircraft's conditions. The runway is 8,202ft long. There is the nearby airport, Gwangju, with two runways, each 9,301ft long.

This was at Muan - 2800m or almost 9200ft. This image doesn't appreciate being linked inline. Or even linked at all.

https://cdn.falcon-bms.com/maps/01_KTO/charts/01 South Korea/Muan/Muan_Airport.png

I don't think it was a residential area. There seem to be a few hotels past that end of the runway, and at least a third of a mile away. And the end seemed to be really short and just concrete (then unpaved) rather than that engineered material that can help to stop an overshooting plane. Looks to be about 1000 ft from the nominal end of the runway to that mound with the antenna array.
 
I can't help but wonder if it had ANY reverse thrust available? Considering how the bottom of both engines had become skid pads, supporting the weight of the entire aircraft as it skidded down the runway.... Until there was none left.
The TR’s wouldn’t be able to deploy with the weight of the aircraft sitting on it.
 
Second- the checklist for the 737 is complex, depending on the issues being experienced. In short, in a belly landing, it would be expected to see Flaps 40, with no use of spoilers or thrust reversers unless stopping distance was critical.

I'm gonna go ahead and say that apparently stopping distance was certainly critical here. (my emphasis above)

I had to chuckle at your answer; my sarcastic and satirical mind works that way. I realize this is a serious topic and I'm not making light of the loss of life. But, I think stopping distance (the lack thereof) is one of several major factors here.
 
I'm gonna go ahead and say that apparently stopping distance was certainly critical here. (my emphasis above)

I had to chuckle at your answer; my sarcastic and satirical mind works that way. I realize this is a serious topic and I'm not making light of the loss of life. But, I think stopping distance (the lack thereof) is one of several major factors here.
You’re not wrong, I was just quoting the checklist.

It’s not desired to use spoilers or TR during belly landings because you essentially have no yaw control and the use of those items can impact the orientation of the aircraft, potentially leading it off the runway.

This accident is a weird one. I’m curious what the investigation uncovers. A lot of things seemed to have happened that don’t make sense.
 
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