Gives me the shivers...

From the Chambers County Sheriff's Office Facebook page:

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Chambers County Sheriff Brian Hawthorne and Lt. Erik Kvarme had the honor this evening of transporting family members of the 3 pilots that were involved in the crash of flight 3591 to the crash site via the Sheriff’s Office airboats. Each family placed a wreath and flowers in the water in honor of their loved ones. Our thoughts and prayers are with families.

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https://cimg8.ibsrv.net/gimg/pprune....9fa8ee852a.jpg

Thank you for your post!

A sad day indeed

RIP

Correction:

Zlinguy, you are correct; I was wrong, the B767 has a single shaft with dual motors, controllers, and brakes. there is a single ballscrew actuator assembly, per Ch 27 IPC and AMM.

Maybe a sudden load shift forward changing the center of gravity but already too low to compensate or counteract. Maybe...:sad:

I wouldn't think that very likely unless it was carrying outsized cargo such as vehicles or engines. (Unlikely on 763 flying Amazon cargo).
In normal cargo operation there would be several pallets/containers and even severe turbulence should not be sufficient to rip out enough cargo locks to enable one of the pallets to move forward and affect the cg.
the w&b manual allows for operation with missing cargo locks and in such instances limitations on cargo loads will still ensure that pallets can not tear free under normal operating conditions.

The 747 crash a few years ago which was caused by military equipment moving used a layout where there were no pallets/containers in front or behind the vehicles to prevent then moving if they tore free.

@JH-CAMO - does atlas use pallets or containers on the 763?

While I agree in principle, the scenario would not be ripping out locks but rather not engaging locks to begin with. If there are a lot of empty positions the pallet can slide fairly easily It has occurred many times in the past.

In that case they would already have had a serious problem on take-off!

Not necessarily. Depends on where the cans are, etc. Seen that one too!

Not necessarily.

If, for example, the forwardmost ULD hadn't been securely locked down, but those behind had, then the problem wouldn't have been apparent on take-off, but on descent.

We're not talking about an accident like Bagram where the cargo moved aft.

Yep, fair enough. But in that case, wouldn't the problem manifest itself earlier in the descent?

Again, too many assumptions here. And again, the answer is "not necessarily". I should add that I view this as an EXTREMELY improbable factor in this accident!

Given the hull loss rate of the 767 (~1 in 10 million departures), pretty much any cause is going to be in the 'very' to 'extremely' improbable range. That's why we never rule anything out until it's shown to be not relevant.

Military Accident-Possibly Similar
 

There was an accident in 1981 involving a military EC-135 that bears some resemblance to this B763 accident.
EC-135 loss of control

Condolences to the families

He forgot Lauda Air Flight 004.

Indeed there are some similarities. Other flights reported IMC conditions, so the onset and what is going on exactly might not immediately have been transparent to the Crew and some ensuing confusion could have delayed possible corrective actions.
That would definitely be one of the somewhat less alien scenarios in this otherwise rather mysterious accident. Although there would still be the question why the Trim ran away. Let's hope they find the boxes soon. Something like this would be rather easy to determine from FDR data.

Impossible. Not enough moment arm for an attitude such as that.

From the NTSB Twitter feed:

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NTSB has recovered the cockpit voice recorder from the cargo jet that crashed in Trinity Bay in Anahuac, TX. CVR being transported to NTSB labs in DC and will be evaluated when it arrives.

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I tried to guesstimate the negative g forces, but that would require the exact time interval from the traces, which is not entirely clear:
1g would take the aircraft from 6000ft to ground in 19 seconds (sqrt(6000/16))
2g would take the aircraft from 6000ft to ground in 14 seconds (sqrt(6000/32))

This accident happened in the dark in the middle of the night, starting at about 33,000 feet. No moon either if I recall. The crew was preparing decent or some other task so they had some lights on in the cockpit. The result was that they had very little to no outside visuals.

When the erreonous high pitch attitude showed up on the fligth display of the PF he didnt cross check with the PM's display, instead he almost instantly pushed control column forward reaching negative G as high as -1G.
VMO at 315 knot was exceeded 17 sec after onset. At 30 sec after onset IA was passing 400 knots and altitude was 24,000 feet. Crashed at near supersonic speed at around -80 degrees pitch and got completely pulverized. It took about 120 sec from onset at 33,000 feet until crash.

On the captains ADI, yes. Not on the other two.

Correct. While you can plot a reasonably accurate profile (altitude vs horizontal position) from the FR24 data, you can't reliably derive anything that's time-dependent as the timestamps (added to the ADS-B data by FR24) are all over the place.

Anyone who doubts that is invited to try to calculate groundspeed by dividing the distance between two successive plots by the interval between the associated timestamps.

Salute!
Seems someone elsewhere mentioned that the two recorders were within 10-15 feet of each other vertically and maybe 20 feet horizontally.
So finding the FDR now seems imminent.
Gums.......

Here's some discussion of 767 stab trim from pprune 15 yrs ago - pprune.org/tech-log/145022-unschedule-stab-trim-b767.html (I can't post links)

at a previous employer we had the elevator feel system freeze due to leaking toilet moisture, and the crew were unable to move the elevators (both columns) during initial level off arriving at destination, they used the stabilizer, after a short while the system unfroze due to warmer air and the airplane returned to ops normal...happened to only one aircraft, twice..system was repaired, never happened again..

Frankly, I'm surprised the former is not a fundamental requirement of forum participation. I'm afraid the latter would exclude me!

I think KAL had two crashes that were caused by following bad attitude displays. B747 and an MD11.

KAL lost the B747-200F at EGSS on 22 Dec 1999 by memory. It had a Capt's ADI failure in roll axis only. The only person who knew what was happening was the Flt Eng, and he resigned to his fate on the way down. The CVR is sobering, as was how close it got to the village. The other ADI and standby were fine until they got mussed up by England's green and pleasant land.

The mega death 2.0 was not caused by any attitude indication failure. The accident report by the state of incident is nonsense, and did not make any sense to the CVR or the radar data which is all that survived. The DFDR was taken out by the APU... The FO was aware of the event as it developed. The underlying causal factor is common on many other aircraft, however, the 2.0 at modest weights can have a wild ride in certain circumstances. Paradoxically, having good performance can result in not having any performance... on 15 Apr 99, the crew got caught out by the interplay of the AP and ATS in high rate events. The logic of the system has been changed since then, but the same sort of interplay still occurs on Boeings to this day. Airbus, this is one event that would not occur in your airplanes, you have other matters to deal with, like full thrust TOGA which adds so much fun to the event. HL7373 was more or less wings level from the event to impact. It did stall twice in the event, once at TOC, and once in the recovery. The last high speed stall probably would have made no difference, the attitude required to meet the available data made a prompt recovery necessary before the pitch attitude had decreased to that in the mid stages of the descent. From approximately 4500' AGL, the aircraft hit the ground in just a little over 16 seconds, from a low speed as recorded by both the radar plot and by the spectral analysis of cockpit wind noise. The behaviour of the autothrottle was identifiable by spectral analysis of the CVR, which showed that where the engine signal was lost due to ambient noise, the 400Hz lines and their harmonics showed the response of the CSD which has a slight delay to the changes in engine RPM; increasing N2 gives an initial overspeed of the CSD which shows as a shift of the 400Hz line, and vice versa for the thrust reduction case. The cockpit broadband noise also provided an SPL solution for speed, which made the modelling of a reasonable flightpath possible in conjunction with the calls of speeds, and the radar data which was pretty sketchy itself. When you are flying your non Bus aircraft, pay some attention to high rate altitude captures with AP and ATR engaged, as during the altitude capture the aircraft is pitching to a rate to achieve the level, which may or may not be within the energy capability of the aircraft. Opposite occurs in a high rate descent capture of an altitude, if you have the boards out, then retracting them once the altitude has been captured will result in a speed excursion dependent on the sink rate and speed at the time of alt cap.

Capturing an altitude from a zoom climb, where you happen to have traded speed for increased vertical rate needs to be carefully monitored, as you may not have enough thrust left to fly the path that is now commanded by the APFD, and you could end up with a reducing airspeed if not intervened.

Filejw: I assure you from hundreds of hours of reviewing 16 seconds of audio, that the crew did not dive the aircraft into the ground, it stalled at TOC. The CAAC report was and is nonsense, and did not match the CVR or radar data. The FO was rather insistent in the last seconds of his life about raising the attitude that the aircraft had achieved in the post stall, and which had a hesitation mid way down from the secondary stall which was evident on the CVR. The hypothesis of a simple push forward from the speed of 240KIAS (by memory that was assumed) but did not match the radar data) was not borne out by kinematic reconstruction or by simulator trials; simply put, you cannot get the plane from Point A to the known Point B in the required attitude at impact, time or distance, which I was also involved in. FYI, the simulator was odd in its own right, we demonstrated 6000FPM + rate of climb in full stall conditions which didn't appear to match either the QTG or the plane itself. The MD11 was an acquired taste; it had more than it's share of issues on landing, from a high approach speed as a freighter, coupled with it's relaxed longitudinal stability which LSAS assisted to some extent. The 10 was a very nicely harmonised plane,

The EGSS aircraft was a -2B5F, (MSN448, HL7451 KAL8509) not a -400. Both of these were messes to clean up.