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Old 10th Apr 2016, 03:34
  #1173 (permalink)  
chuks
 
Join Date: Apr 2003
Location: Germany
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Just questions, not necessarily misconceptions, because that narrative raises more question than it answers.

For me it starts with this "yolk/yoke" business, which I have encountered previously. It's a red flag, although it might also be something of no real significance. After all, "On the internet, nobody knows you are a dog."

I understand how the pitch trim works by moving the stabilizer, thank you. It was one of the first things they taught me, along with that that thing you yank on is called the "control yoke." In this scenario, though, the trim is grossly out, set for (full?) "nose-down," yet the PF is able to pull full "nose-up" against it, when the aircraft does not respond to that because of the trim being set nose-down. That implies that the trim had to be rapidly re-set, what, full nose-down during the go-around? Who does that, and why? Too, you are pulling with all your might against the pitch trim, without bothering to operate the pitch trim switch which is right there on the yoke? That should be reflex, I would think.

I guess we would need to be told how OKC "found it quite easy to produce a set of (seemingly innocuous) control, power, and trim inputs that would lead to the outcome that [he] experienced," such that "any sufficiently experienced B737 pilot could probably easily replicate the same, with a little imagination."

In other words, a go-around results in a fatal impact at a 40º nose-down angle with increasing airspeed at zero thrust because of control, power and trim inputs. That's a pretty alarming scenario because I can not imagine what those "inputs" from a "sufficiently experienced B737 pilot" might be. I think we need to be told a bit more about that, because this seems to be a very implausible narrative, just on the face of it.

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!

Another thing: I doubt that professional accident investigators pay very much attention to posts made here, but non-pilot members of the public, and some reporters too, probably do read these posts.

I just watched that clip from the sim reenactment, linked above and mentioned below, and found it completely uninformative. We need to be able to read the instruments, see the pitch trim settings, and see the PF control inputs in order to understand what we are being shown there, other than "a crash." What is the point of making such a video as that one?

Last edited by chuks; 10th Apr 2016 at 04:43.
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