China Eastern 737-800 MU5735 accident March 2022
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My first thoughts on seeing the raw video. Some of the debris, not found in the hole, seem to be winglets and other wing or tail parts. Maybe nothing to do with the cause.
Right Wing tip.
Let see what the investigating team comes up with.
Last edited by Cool banana; 21st Mar 2022 at 18:22.
Ref the wing parts that appear to have separated, I suspect from their state and the descent profile, that the aircraft reached its divergence speed and the outboard wings came off. This would not be the root cause, but an indirect result of an earlier problem that produced the extreme dive angle. It has happened before - a B737-200 flown by Copa (Panama) sometime in the 90s.
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Looking at the last data points: GS 376kts VS 30976 ft/min = ~305 kts. Decent angle is arctan(305/376) = 39 degrees. <please check my maths!> Based on the video evidence, it suggests that AOD increased markedly in the very last phase of the decent. Maybe up until this point, the A/C was relatively intact but suffered some significant break up close to the ground.
Looking at the last data points: GS 376kts VS 30976 ft/min = ~305 kts. Decent angle is arctan(305/376) = 39 degrees. <please check my maths!> Based on the video evidence, it suggests that AOD increased markedly in the very last phase of the decent. Maybe up until this point, the A/C was relatively intact but suffered some significant break up close to the ground.
Somebody made a graphic here; you can see some attempt at recovery, maybe (at 06:22:16 UTC) - or, change of configuration of surfaces (non-pilot initiated, e,g; further structual failure) resulting in change of flight path. Or, again. this could be FR24's Algorithyms's interpolating unusual data and as a result plotting erroneous trajectory.
Obviously, the blue aircraft symbol is not representative of the aircraft's attitude but simply it's position in altitude and even then - only very approximately and exaggerated for illustration purposes.
So a pointless task of guessing. The only thing that will clarify what happened is the boxes.
Last edited by Auxtank; 21st Mar 2022 at 19:30.
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Weather at crash time, sat pic, lightning
Hello, since it was mentioned earlier in the thread:
Doesn't look like anything remarkable, you can click into the district or change time if needed.
Visible sat pic
IR Sat pic
Lightning detection
Doesn't look like anything remarkable, you can click into the district or change time if needed.
Visible sat pic
IR Sat pic
Lightning detection
Hello, since it was mentioned earlier in the thread:
Doesn't look like anything remarkable, you can click into the district or change time if needed.
Visible sat pic
IR Sat pic
Lightning detection
Doesn't look like anything remarkable, you can click into the district or change time if needed.
Visible sat pic
IR Sat pic
Lightning detection
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Dear Sir, please can you tell me if any airliner in modern commercial aviation history has been brought down by lightning or CAT?
Looking at FR24 data, did they overshoot their TOD? Did they try and rush the descent and something happened? The investigators will be checking out the maintenance history of this bird. It's a fairly new plane but has it had any repairs recently? What about tail strikes lately?
Looking at FR24 data, did they overshoot their TOD? Did they try and rush the descent and something happened? The investigators will be checking out the maintenance history of this bird. It's a fairly new plane but has it had any repairs recently? What about tail strikes lately?
Rudder or the whole vertical stabilizer sheering off wont create such a rapid fall. Remember there is airspeed and Ailerons and Elevators should still be effective, assuming symmetrical thrust. Only the directional control is lost.
Intentional dive or Runaway nose down stabilizer is what I can think off. The video seems too unrealistic.
Intentional dive or Runaway nose down stabilizer is what I can think off. The video seems too unrealistic.
https://www.pprune.org/archive/index.php/t-457960.html
What would it do to the integrity of the hydraulic lines running to the rudder? And thus the availability of hydraulic control pressure for elevator operation?
Dear Sir, please can you tell me if any airliner in modern commercial aviation history has been brought down by lightning or CAT?
BOAC 911
The investigation concluded that the vertical stabiliser came off first.
The Flightradar24 table presented earlier shows a speed of maximum speed of 590kts around the point of the vertical speed reversal. The airspeed was possibly faster. Very fast for an airliner at 8000'. As for the G loading at the point of the vertical speed reversal, my guess is it was probably very great in the positive or even negative direction.
Massive nose overs have occured in the past (in Military and General Aviation) as a consequence of losing Horizontal stabilizers. If the FR24 is valid this could potentially happen due to exceeding the structural limit in the first apparent recovery (if the FR24 traces are correct). That said in one of the videos the final trajectory rather looks like 50° ND and possibly with a slight recovery path. The other video on the other hand looks pretty vertical. Simply not possible to safely conclude from the few bits we have. First important information bit to obtain woould be the four corners. After that there is a first chance to get a somewhat clearer picture.
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[QUOTE=fdr;11203404]Last bits that looked like that I examined had a flutter-type event from going deep into the buffet boundary. Shredding laminate is not a very common failure mode.
more parts of the right wing tip mid leading edge and inboard right logo panel
That is part of the wingtip not the rudder
more parts of the right wing tip mid leading edge and inboard right logo panel
That is part of the wingtip not the rudder
Re a previous poster's comments about asymmetry, the track was remarkably constant until the 30000ft/min descent rate was well established. This implies the autopilot may have remained engaged for some time. Even an engine failure with autopilot engaged would show some track change.
Edited,
There was also clearly a recovery and even a brief climb so the initial upset event cannot have been totally catastrophic.
Edited,
There was also clearly a recovery and even a brief climb so the initial upset event cannot have been totally catastrophic.
Last edited by Consol; 21st Mar 2022 at 23:26.
Re a previous poster's comments about asymmetry, the track was remarkably constant until the 30000ft/min descent rate was well established. This implies the autopilot may have remained engaged for some time. Even an engine failure with autopilot engaged would show some track change.
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Unfortunately PILOT SUICIDE is the most likely reason for this crash.
Rudder hardover, Stab trim runaway, mishandling a depressurisation WILL NOT result in a descent profile like this. I’ve tried it in the sim and the descent profiles are NOT near vertical like this.
SILKAIR flight MI 185 is a very similar example to compare. Deliberate, sustained pilot input with stab trim at full manual nose down and a high thrust setting was determined as the cause of this crash by the NTSB as an addendum to the final report.
Rudder hardover, Stab trim runaway, mishandling a depressurisation WILL NOT result in a descent profile like this. I’ve tried it in the sim and the descent profiles are NOT near vertical like this.
SILKAIR flight MI 185 is a very similar example to compare. Deliberate, sustained pilot input with stab trim at full manual nose down and a high thrust setting was determined as the cause of this crash by the NTSB as an addendum to the final report.
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Let's let facts and Data rule - not idle speculation
- Profound sympathy to the crew, pax and their families.
- More data is needed to even start any credible assessment. Like the distribution of remaining identifiable parts, any ATS communication, preliminary failure mode of identifiable pieces, etc.
- an ultimate pitch tuck can have many many root causes
- much of the above speculation is both technically way off-base, and very unfair to the families of the lost flight crew, pax, ....and even to the airline at this point.
- let's hope a credible internationally staffed accident team can be fielded ASAP, and the results honestly, credibly, and quickly reported.
- There are just too many NGs we're flying out there, to not have credible bounds being placed on the inaccurate speculation now being distributed... ASAP.
- Let's hope for usable DFDR, QAR, and CVR data... but in accidents like this, that can be long shot.
- Profound sympathy to the crew, pax and their families.
- More data is needed to even start any credible assessment. Like the distribution of remaining identifiable parts, any ATS communication, preliminary failure mode of identifiable pieces, etc.
- an ultimate pitch tuck can have many many root causes
- much of the above speculation is both technically way off-base, and very unfair to the families of the lost flight crew, pax, ....and even to the airline at this point.
- let's hope a credible internationally staffed accident team can be fielded ASAP, and the results honestly, credibly, and quickly reported.
- There are just too many NGs we're flying out there, to not have credible bounds being placed on the inaccurate speculation now being distributed... ASAP.
- Let's hope for usable DFDR, QAR, and CVR data... but in accidents like this, that can be long shot.
- Profound sympathy to the crew, pax and their families.
I'm a tad suspicious of the video. It looks very much like one of a crashing Long March booster from a couple of years ago.
https://cdn.images.express.co.uk/img...=1599550692168
https://cdn.images.express.co.uk/img...=1599550692168
Paxing All Over The World
In trying to ascertain what speed it was falling at, does anyone know what ther terminal velocity would have been - and how long to reach that from the start of the fall? The media are putting all sorts of numbers on the vertical speed, doubtless some from here.