Originally Posted by
Flocks
You can try as much to understand what happened in their brain, you won t ... read the AAIB report (link at the beginning of the forum). In the world of Dash 8, I m sure it is not the first time pilot take off with wrong setting of FD, it is just probably the first time it went that far before reaction ... But they did appropriate reaction with the ground proximity warning and continued the flight safely.
we can all do mistake, we are all Human ... But we can all learn from mistake of other instead of saying : it won't happen to me, impossible, I can't do this kind of mistake ...
I read the AAIB bulletin which I had skipped over before, so thanks for pointing me to it. It explicitly answered one of my questions:
"During the next 15 seconds, whilst the crew were completing the ‘after takeoff’ checklist, the aircraft descended at an increasing rate with the pitch attitude reducing from about 10° nose-up, to 8° nose-down."
This aspect of the scenario is well-addressed at my airline, where the after takeoff checklist is done entirely by the PM, silently; and I'm glad for that.
Another interesting find from the bulletin is that it lists 3 similar incidents from the same operator. In 2 of them, they saw the pitch down after AP engagement right away, and stopped it after about 150 feet. In the third, they saw the misset modes and fixed them before AP engagement.
As far as being unable to understand what happened in their brain, I'm not sure whether you mean in general, or about this incident. But eiter way I disagree. Sometimes you're left with no answer, sometimes you end up with a fairly good guess, and sometimes it's obvious. But at any rate, from our perspective as pilots it's very important to try to learn that lesson so we don't repeat it ourselves, as it is a cause of the accident chain. It's just as important as the guys who piece together the aircraft to find out what broke before impact, or read the FDR to see the sequence of mechanical events, etc.
As far as the brain-sequence of this particular incident, it's becoming clearer and clearer to me, thanks to:
- the description in the AAIB bulletin
- info from you guys who have flown the type
- similar experiences of my own
Something not yet mentioned in the thread is that they were rushed to takeoff with a late second engine start, a quick flurry of accomplishing the remaining procedures, one of which was interrupted by the takeoff clearance. Introspection moment #1: This happens to us
all the time. Even though when I shake hands with the Captain after sitting down for leg #1 and he goes through the usual introductory spiel which most of the time includes something like "we won't ever let ourselves get rushed, that's when you miss stuff and mistakes happen. If we ever need more time, we own the parking brake and we'll make more time;" Yet it happens anyway.
So they do the last-second flurry of checklists, during which, by the way, they do catch that the modes are wrong! But unfortunately fix only part of the problem, leaving the modes still misset. Introspection moment #2: When rushed and you fix a problem, it's extremely easy to feel that mental reward of fixing it: "Aha! all good now" and don't necessarily take the step back and make sure the big picture is OK, which may include a still-unfixed second or third part of the problem. By getting that "aha!" you feel satisfied to continue on.
So they do that, continue with the takeoff, fail to notice that the pitch bar is "down there in the brown" as I noted in my previous post, and engage the AP at the routine time. Now that the AP is on, we can all rest easy right?
And this should be an introspection moment for all you guys where the SOP has both pilots involved in the after takeoff checklist.
For me introspection moment #3 comes where my type has a much simpler vertical mode scheme and it is literally impossible to make this particular mistake. If I ever move to a type like the one in this incident, can I bring some of my habits with me? Even if I fastidiously follow the new SOP, can my old habits rear up in a moment of hurry and/or high workload?