Chuks said:
Strange things do happen; there have been other crashes that require reading the final report to understand how they could have happened, when that was because of very strange control inputs on the part of the crew. (That Colgan crash near Buffalo is probably the worst example of that, when even the accident investigators had no real answer to why the crew flew the airplane as they did, when their strange control inputs caused the crash.) Here we have an equally strange scenario being presented in a veiled manner, out of fairness to the official inquiry (?). Okay, if you say so!
However, this I agree with 100% This is a concern of mine in this event.
Chukss also said:
It's completely unrealistic for OKC to tell us of a scenario where he is pulling with all his might against the trim without bothering to re-trim using switches that are right there on the yoke. Who would do that, especially given that they would have been using those same switches shortly before to re-trim the aircraft? It is not as if the PF is going to suddenly forget to use the same secondary flight control, pitch trim, that he already had been using, is it? This is not, at first glance, a realistic scenario, so that we need to be told more about how it's supposed to have come about.
If you look at my posts, I am with the notion that a crew who already performed a go-around and were expecting to make another go-around and then flew what appears to be a stable second go-around with all the available parameters consistent with such, then suddenly end up diving at 13,500 FPM in 7 seconds from a 1350 FPM climb cannot possibly be explained away with just crew error.
However, I can understand how, once trimmed fully nose down, if the speed is allowed to builds sufficiently, then even full aft elevator may be enough to recover the aircraft. With 4 units of trim, I could never have imagined it but I can accept it. With zero units and the flaps ripped of I can easily believe it.
But, what is most puzzling is why the half way down the descent, the flight path steepened still further. Any attempt to pull back on the stick would have resulted in, at worst, a pitch up, however slight and whatever the trim. Perhaps there is a point at which the elevator becomes stalled and looses all effectiveness?
But as Chuks ponders, if there was nothing wrong with the aircraft, why not simply trim nose up. It is inconceivable how this was not the first and initial reaction of even the most fatigued, surprised, shock, scared and startled crew member, never mind crew members!
BTW, any bank angle can easily be explained away. At high speed, even the slightest and gentlest input will result in an instant response and roll - even with no intention to bank the aircraft it would be unlikely that a crew trying to recover won't command some roll at such speeds. The aileron feel system uses only springs and does not replicate dynamic aerodynamic loads in the same way as the elevator system.