Swift 737-400 crash on final to Vilnius (Lithuania)

[Gabriel]

https://avherald.com/h?article=520c0e2b&opt=0

RIP to one fatality. Hoping the best for 3 injured (apparently 2 of them very badly injured).

I am going to start the speculation with 2 hypothesis:
- Dual engine loss
- Inadvertent automation-related speed degradation (like in Turkish and Asiana)

[bstolle]

A much better view, but it still leaves a lot of question unanswered...
Both of your speculations fit this scenario.
Išskirtiniai kadrai: nuo Liepkalnio slidinėjimo trasos – lėktuvo katastrofos momentas

[Gabriel]

A much better view, but it still leaves a lot of question unanswered...
Both of your speculations fit this scenario.
Išskirtiniai kadrai: nuo Liepkalnio slidinėjimo trasos – lėktuvo katastrofos momentas

Stall and uncommand roll. When I said dual engine loss I was thinking of a controlled forced landing, but it could be a stall while trying to stretch the glide.
However, now I lean more towards the Turkish-like scenario. Engine left at idle due to automation failure (like in Turkish) or wrong mode selected (like in Asiana), speed deteriorating while AP keeps increasing the pitch to keep the glide slope at an ever-reducing speed, until it disconnects with stickshaker.

[Evan]

Maybe the video speed isn't in real time and who knows the configuration but it seems to me that they are moving at a healthy margin above stall speed for that flight path. I'm thinking it might be a good old fashioned 737 hard over. This is an antique -400 and that empennage design is a Rube Goldberg mechanical complication that needs disciplined maintenance. Most of these things come down to pilot error rather than airframe age, but this might be one of those exceptions. But as we don't really have enough to speculate with yet, so that's just a hunch.

The Turkish scenario requires a malfunctioning radio altimeter and a flawed autothrottle computer that wasn't introduced until the NG. But it appears to be moving too fast for that scenario.

Just read that more carefully and caught the loss of comms part. So perhaps incapacitation or a distracting emergency (fire?)...

How did ANYONE survive that?!

[Gabriel]

Maybe the video speed isn't in real time and who knows the configuration but it seems to me that they are moving at a healthy margin above stall speed

On one hand I have the same sensation (and many people mntioned the same in may internet comments).
On the other hand, after playing the video frame by frame, at a point before the roll the blinding lights are obscured by a truss structure and I think that I see the plane at a somehow high pitch, and during the roll the nose seems to go quite a bit up too (which is the opposite of what you would expect with a rudder hardcover since that creates a nose-down pitching moment once the airplane banks). Or I can be seeing things because in all honesty the video is not very clear at all.

I'm thinking it might be a good old fashioned 737 hard over.

I will not discard that

The Turkish scenario requires a malfunctioning radio altimeter and a flawed autothrottle computer that wasn't introduced until the NG.

I didn't say the specific Turkish scenario. I said engine left at idle due to automation failure or mismanagement.
This has happened several times in the 737 (not only, as Asiana can prove) due to different reasons. The only common factor is all them is that the engines are at or close to idle, the speed decays, the pilots don't realize until too late (well, I guess that more than one factor in common)

Just read that more carefully and caught the loss of comms part. So perhaps incapacitation or a distracting emergency (fire?)...

They red back the wrong tower freq and were not corrected by approach. This could have caused a distraction while trying to see why Tower was no answering their call and trying to figure out if the frequency was correct. That would also prevent any distress call to be heard by ATC even if one was transmitted (in a wrong frequency). CVR should tell.

How did ANYONE survive that?!

More speculation: They were very low then they rolled, probably the plane didn't have time to develop a high vertical speed. Wing (and trees) partially absorbed the energy. The fuselage still sled a few hundred feet or meters after impact leaving the fire behind. And an amount of luck comparable to winning $1 billion in the Powerball.

[Evan]

On one hand I have the same sensation (and many people mntioned the same in may internet comments).
On the other hand, after playing the video frame by frame, at a point before the roll the blinding lights are obscured by a truss structure and I think that I see the plane at a somehow high pitch, and during the roll the nose seems to go quite a bit up too (which is the opposite of what you would expect with a rudder hardcover since that creates a nose-down pitching moment once the airplane banks). Or I can be seeing things because in all honesty the video is not very clear at all.

There is another video angle where the pitch seems to go nose-high just prior to impact, perhaps prior to the roll. Again, it's based on lights, not a distinct fuselage. It sort of looks like a last ditch panic attempt to arrest the descent but too late to have much effect.

I didn't say the specific Turkish scenario. I said engine left at idle due to automation failure or mismanagement.
This has happened several times in the 737 (not only, as Asiana can prove) due to different reasons. The only common factor is all them is that the engines are at or close to idle, the speed decays, the pilots don't realize until too late (well, I guess that more than one factor in common)

If I recall correctly, there were 12 prior incidents before the Turkish crash, with the common factor being that lemon of an autothrottle computer.

[3WE]

One of my best MSFS learnings was half ass descending through a cloud deck.

I wasn’t paying attention, broke out, thought “oh shit the ground” while simultaneously pulling up.

BEFORE I COMPLETED “THE THOUGHT”, it was over.

One can dream up a lot of variants on suddenly getting too low when it’s too late to pull up, and some are present here.

[Evan]

We are dealing with some optical illusion in those videos. In one video, it appears to me like a sudden nose down, but that's probably a roll. In another, it appears to me as a sudden nose up, but no roll before it drops into the trees. I don't put any faith in any of these perceptions, except that it seems to be at a healthy airspeed for a proper configuration and go-around attitude.

[Snuggleposs]

The videos are so inconsistent we can only speculate what happened we aren’t the NTSB we don’t have access to all the info but we still can try to help.
Also on flightradar24 the flight seemed normal. I don’t know if this is right but the rate for decent seemed off it was going from -300 Fpm.

[xspeedy]

I think this cropped one may be best. Looks like the left wing dropped and struck terrain. But it may have suddenly yawed to the right at the same time?

https://apnews.com/video/lithuania-plane-crashes-c27eeace611d40189b707d4543f15569

[Evan]

It does appear that way. Pitch appears nose up but not relentlessly. Could be a stall. Especially if icing is involved.

[3WE]

It does appear that way. Pitch appears nose up but not relentlessly. Could be a stall. Especially if icing is involved.

Or you had a decent sink rate, or slow speed…

[FBI_Agent]

Looking at the footage, it might've been a malfunction somewhere in either the right wing or the cockpit. It looks like they slightly bank to the left but suddenly get forcefully thrown right into a roll.

[3WE]

Looking at the footage, it might've been a malfunction somewhere in either the right wing or the cockpit. It looks like they slightly bank to the left but suddenly get forcefully thrown right into a roll.

…Evanie mentioned the hard-over history.

[flashcrash]

The video that (apparently) shows the sudden turn and roll to the right has me worried. I do hope this isn't an example of the rudder-jam problem that the NTSB was clamoring about in September, and for which the FAA finally issued a Safety-Alert-To-Operators in October.