Ok, I read it. The pitch moment/AoA factor is technically interesting but also momentary and I have to ask how significant a factor that is in contributing to a real-world fully developed stall. Is it really enough to silence stickshaker more than momentarilly or even at all?
Also, does "the pitching moment of the the thrust may overpower the elevator" apply to the Dash 8 or any t-prop where the tractor propulsion is practically in-line with the wing?
But mainly this:
Whaat? If pitch and power are not a direct means to control AoA, what is? In wings-level flight, what does elevator control if not pitch? Is elevator not the main means of controlling the pitch axis? Have I had that wrong all along?
Lets rewind. You wrote:
To which I contended that, while not the optimized modern procedure, at proximity to stall (onset of stickshaker) in this aircraft (a Dash 8 ), when not pitching up 10° or even 1°, it should be possible to recover with power alone. I also added that this procedure (power first, then manage pitch) would involve a forward pressure to prevent pitching up (NOT hands-off) and ideally reduce pitch slightly but not so much that results in a significant loss of altitude.
Since power=airspeed and airspeed lowers AoA if elevator (forward pressure) maintains current pitch, I can't find in your reply why this isn't true.
EX: a Dash 8 is flying at 6° ANU and speed gradually falls off, thus increasing AoA to stickshaker (approach-to-stall margin below critical angle). Pilot first firewalls throttle, then applies yoke pressure as needed to maintain 6° ANU. Not the safest course of action but shouldn't that work?
2ND EX: Same as the above but pilot applies forward yoke to maintain 4° pitch.
Both with no configuration changes.
In the end you are reaching the same conclusion I did when I read this, which is that the pilot probably overreacted in the full-stall recovery and put the aircraft much closer to terra firma than he should have. I agree that this is better than the opposite reaction (not enough) that would have put it squarely on terra firma.
But isn't the problem in both cases flawed procedure? Why must we choose between these extremes, between stall and CFIT?
And, of course, the real issue here is that the PF did not use any procedure to lower the AoA at stall warning, but rather let the airplane pitch up into a stall.
Also, does "the pitching moment of the the thrust may overpower the elevator" apply to the Dash 8 or any t-prop where the tractor propulsion is practically in-line with the wing?
But mainly this:
So, with this theoretical exception for which I have never seen a case, we must say that ELEVATOR CONTROLS AOA (again, including trim). Not pitch and power (which can affect AoA, but are not a direct means to control it).
Lets rewind. You wrote:
As soon as the stickshaker starts, the captain applies full power and pitches 10° nose-up. Wasn't that the standard stall recovery procedure "by the book" back then? The plane still stalls. Here we go with the "power (alone) to recover a proximity to stall"
Since power=airspeed and airspeed lowers AoA if elevator (forward pressure) maintains current pitch, I can't find in your reply why this isn't true.
EX: a Dash 8 is flying at 6° ANU and speed gradually falls off, thus increasing AoA to stickshaker (approach-to-stall margin below critical angle). Pilot first firewalls throttle, then applies yoke pressure as needed to maintain 6° ANU. Not the safest course of action but shouldn't that work?
2ND EX: Same as the above but pilot applies forward yoke to maintain 4° pitch.
Both with no configuration changes.
In the end you are reaching the same conclusion I did when I read this, which is that the pilot probably overreacted in the full-stall recovery and put the aircraft much closer to terra firma than he should have. I agree that this is better than the opposite reaction (not enough) that would have put it squarely on terra firma.
But isn't the problem in both cases flawed procedure? Why must we choose between these extremes, between stall and CFIT?
And, of course, the real issue here is that the PF did not use any procedure to lower the AoA at stall warning, but rather let the airplane pitch up into a stall.
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