China Eastern 737 down

[boeingboy]

I dont know where this info is coming from about a short climb - I find that impossible.

I had a look at the flight radar data and it shows no climb. Diving near vertical is going to very quickly exceed VNE and shortly thereafter the vertical and horizontal stabs are going to come off the airplane. Even if it managed to stay in one piece - in order to reverse a dive like that would take time and the G forces involved would itself tear the plane apart....nevermind it having to reverse again back into a dive, and then all that in under 2 min....not going to happen.

Silk air 185 was a 737-300 a number of years ago - it was ruled a suicide....but in testing you needed full forward control and full nose down trim and the airplane still wanted to recover itself. It was very difficult to hold a 60 degree nose down attitude. In that accident - the airplane ripped itself apart at about 10000 feet.

I saw a dash cam video of this latest one where it look 60 - 70 degrees nose down.
https://www.reddit.com/r/interestingasf ... _by_china/

[Tolip]

I would agree with you on that. But flight radar shows the plane leveled off and managed to climb about a thousand feet before continuing into another nose dive. I think just that there almost rules out critical aircraft failure

Not necessarily. The aircraft could have been overstressed pulling out of the initial upset resulting in structural failure resulting in the final uncontrolled dive.

All speculation at this point.

100 percent. All just speculation, you guys are right. You can never eliminate anything in these situations, but I do think that the level off and subsequent climb are good initial indication it was something outside of critical aircraft failure that caused the crash. But that does kinda get you thinking, what else could it be? It was an insane decent from what I saw in the video posted above

[boeingboy]

No dive recovery...the speed apparently decreased momentarily at 6500 feet and then climbed back - so maybe some reporter confused the 2 scales. It was probably a glitch in the data due to speed, decent, and terrain.


Absolutely no climb or recovery. From 9000 feet to the ground in just under 20 seconds.

Speed:
06:22:16 - 455kts......9000 feet
06:22:27 - 413 kts.....6500 feet
06:22:31 - 442 kts.....4000 feet
06:22:35 - 376kts......3200 feet - - - end of data.

https://www.flightradar24.com/data/flig ... 5#2b367bc1

[Tolip]

I dont know where this info is coming from about a short climb - I find that impossible.

I had a look at the flight radar data and it shows no climb. Diving near vertical is going to very quickly exceed VNE and shortly thereafter the vertical and horizontal stabs are going to come off the airplane. Even if it managed to stay in one piece - in order to reverse a dive like that would take time and the G forces involved would itself tear the plane apart....nevermind it having to reverse again back into a dive, and then all that in under 2 min....not going to happen.

Silk air 185 was a 737-300 a number of years ago - it was ruled a suicide....but in testing you needed full forward control and full nose down trim and the airplane still wanted to recover itself. It was very difficult to hold a 60 degree nose down attitude. In that accident - the airplane ripped itself apart at about 10000 feet.

I saw a dash cam video of this latest one where it look 60 - 70 degrees nose down.
https://www.reddit.com/r/interestingasf ... _by_china/

It's all spotty information that is comming out, probably none of it should be trusted yet at this point. Agreed there. But the bit about the level off and climb came from a Bloomberg article posted earlier today. I linked it above

[boeingboy]

It's all spotty information that is comming out, probably none of it should be trusted yet at this point. Agreed there. But the bit about the level off and climb came from a Bloomberg article posted earlier today. I linked it above

Look at my comments and data above yours.

[goldeneagle]

No dive recovery...the speed apparently decreased momentarily at 9000 feet and then climbed back - so maybe some reporter confused the 2 scales. It was probably a glitch in the data due to speed, decent, and terrain.

https://www.flightradar24.com/data/flig ... 5#2b367bc1

discussion of a climb comes from this plot of adsb data available at the dailymail.



29,000 to impact in 2 minutes is a significant vertical speed, have no idea how the overall airspeed looked.

[boeingboy]

No dive recovery...the speed apparently decreased momentarily at 9000 feet and then climbed back - so maybe some reporter confused the 2 scales. It was probably a glitch in the data due to speed, decent, and terrain.

https://www.flightradar24.com/data/flig ... 5#2b367bc1

discussion of a climb comes from this plot of adsb data available at the dailymail.



29,000 to impact in 2 minutes is a significant vertical speed, have no idea how the overall airspeed looked.

Weird - looks much different than the flight radar data I linked...and the time and speed dont match either.

[Tolip]

No dive recovery...the speed apparently decreased momentarily at 9000 feet and then climbed back - so maybe some reporter confused the 2 scales. It was probably a glitch in the data due to speed, decent, and terrain.

https://www.flightradar24.com/data/flig ... 5#2b367bc1

discussion of a climb comes from this plot of adsb data available at the dailymail.



29,000 to impact in 2 minutes is a significant vertical speed, have no idea how the overall airspeed looked.

Weird - looks much different than the flight radar data I linked...and the time and speed dont match either.

Like I said, all the data is a little spotty still. I believe that level off ( if true) more or less rules out aircraft structural failure as the initial cause
Itss reported as a -800 modle (which would rule out mcas issues)
the -800 has no history of any accident like this in it's almost 30 years of flying.
Also no reportable weather to speak of

So my mind now goes to intentional CFIT. Perhaps the brief level off was due to who ever was at the controls having a change of heart, but the subsequent level off lead to structural failure. Which, afterwards led to that crazy nose dive that was captured in the video above?

That's my best, any other crazy theories out there?

[boeingboy]

We will just have to wait for the recorder data....

Flightradar24 data below...

[Tolip]

We will just have to wait for the recorder data....

Flightradar24 data below...

I think your misreading the graph, I had to take a second look at it aswell. At about 6:21 and 40 seconds, it starts to level off, and at 6:22 and 40 seconds it disappears. So from the level off to crash 1 minute passes. About 2 minutes for the whole incident

[goldeneagle]

The Alaska Air crash stopped the dive momentarily as well before diving again.

My understanding of that one, pulling up wasn't working so they tried to push to inverted, that sort of worked, then they ended up back into the vertical dive.

The adsb plot from dailymail has a similar set pof data points.

Does the 737 use jackscrews to control the stab ?

[goldeneagle]

We will just have to wait for the recorder data....

Looking at the drone footage of the crash site, not sure there will be any recorder data.

Another clip from the dailymail

[AirFrame]

More graphs, and screenshots of the KML file in google earth showing the ADS-B tracking points:

https://twitter.com/AaronCh91089298/sta ... 7114792966

There's an initial "jump to the left" in the track, followed by a rough arc down and to the right. If the rudder had been kicked to one side, it could have rolled left and ended up in a counter-clockwise spiral dive that recovered down near 7000' and over Vne... The g-forces in the pull causing wing failure? Or maybe a rudder actuation caused the vertical stab to separate, and they lost it before they could get it stable with asymmetric thrust?

[fish4life]

We will just have to wait for the recorder data....

Looking at the drone footage of the crash site, not sure there will be any recorder data.

Another clip from the dailymail

That hole looks like one of the max crashes and they got that data recorder. Although this one was more extreme

[Maritimer]

More graphs, and screenshots of the KML file in google earth showing the ADS-B tracking points:

https://twitter.com/AaronCh91089298/sta ... 7114792966

There's an initial "jump to the left" in the track, followed by a rough arc down and to the right. If the rudder had been kicked to one side, it could have rolled left and ended up in a counter-clockwise spiral dive that recovered down near 7000' and over Vne... The g-forces in the pull causing wing failure? Or maybe a rudder actuation caused the vertical stab to separate, and they lost it before they could get it stable with asymmetric thrust?

Could this be another accidental rudder trim activation instead of flight deck door unlock? It has happened before

[boeingboy]

Looking at the drone footage of the crash site, not sure there will be any recorder data.

Both Silk air 185 and PSA 1771 were put into vertical dives and exceeded the speed of sound before disintegrating on impact with the ground. The recorders were recovered in both cases.

PSA 1771 (BAE 146)...

Shutterstock_6571944b.jpg (316.6 KiB) Viewed 3020 times

[Gear Jerker]

I've seen a few posts on PPrune that suggest there are always 3 pilots in the flight deck of Chinese majors; can anybody confirm or deny this? If so, the Silkair/Germanwings cause strikes me as more unlikely.

Fingers crossed for good news about CVR/FDR memory soon.

[co-joe]

Could this be another accidental rudder trim activation instead of flight deck door unlock? It has happened before

I'm assuming this is the case you are talking about.
https://aviation-safety.net/wikibase/138837

I had never read or heard about that case. I've also never seen a 737 with that layout for the location of the rudder trim and door lock switch, but I'll certainly be aware of it. The 737 has lots of switches and knobs that look nearly identical. I've heard first hand of people accidentally turning the electric hydraulic pumps off by mistake instead of the engine anti ice, as well as turning the ignition switches on by mistake instead of the wind shield wipers. Neither of those cause control problems though.

[Eric Janson]

I've heard first hand of people accidentally turning the electric hydraulic pumps off by mistake instead of the engine anti ice

I had a FO do exactly this on the climb out on a 737-300.

The moment he moved the electric pump switch to off he immediately moved it back on. The power spike tripped the left generator and caused a loss of all EFIS displays on my side and tripped off the autopilot.

I had to transfer control to the FO and he had to fly manually while I sorted things out.

The left generator could not be re-connected - I finally needed to start the APU and connect that to the left side of the electrical system. After 10 minutes I was able to replace the APU with the left generator.

As stated earlier - no issues with flight controls - but a potential high workload situation requiring manual flight.

No idea if the 737-800 electrical architecture is the same.


Back to China Eastern

https://www.youtube.com/watch?v=q4-Dj63 ... lancolirio

The data he shows also shows a slight climb before the final dive - similar to what has been posted on PPRuNe.

[boeingboy]

CVR has been found.

From Avherald...

The captain had accumulated 6,709 flight hours total, the first officer 31,769 flight hours, the second officer 556 hours, all of them in good family relations. The aircraft was in an airworthy condition, all maintenance had been done in strict compliance with regulations and requirements.

In a third press conference the CAAC reported although the black box is badly damaged, the storage unit looks intact and has been determined as the Cockpit Voice Recorder CVR. It has been sent to Beijing for download and decoding. The second officer was an observer to increase experience.