Minimum height for practice stall recovery in C172
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Wing at 16 deg AOA, stalled, wing at 15 deg AOA, unstalled. Height loss about 10ft at most, as you move the stick fwd a fraction to effect the 1 deg pitch change.
Now going from 16 deg AOA stalled to 0 deg AOA nose at 20 deg negative pitch dive while pushing full power, then you will lose far to much height than actually needed to recover..
What method is taught the most and why?
And which method of stall recovery would you prefer if you stall on mid or short final? (Yes, final, not finals, you can only fly 1 final at a time)
bury the nose into the ground recovering, or just releasing enough back pressure to get the wing from 16 to about 15 or 14 deg AOA, where it will still fly happily, unstalled. Even in a turn.... assuming you know how to use a rudder and the ball is centered.
Now going from 16 deg AOA stalled to 0 deg AOA nose at 20 deg negative pitch dive while pushing full power, then you will lose far to much height than actually needed to recover..
What method is taught the most and why?
And which method of stall recovery would you prefer if you stall on mid or short final? (Yes, final, not finals, you can only fly 1 final at a time)
bury the nose into the ground recovering, or just releasing enough back pressure to get the wing from 16 to about 15 or 14 deg AOA, where it will still fly happily, unstalled. Even in a turn.... assuming you know how to use a rudder and the ball is centered.
Based on the way I've seen stall recoveries taught in most flying schools I'd like to be above 3000 feet. Based on moving the stick just forward of the stalling position, I'd quite happily venture below it.
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While we are talking stalling, from discussion with some newbies it seems they recover at the point of stall.
Next time you are up in a suitable aircraft, above 3000' by a margin:
Try stalling and NOT recovering straight away!
Hold full back stick to keep the aircraft in the stall for as long as you like, keeping wings level with rudder ( or even aileron - give it a go!) until, when you wish to recover, simply move the stick/column forward to reduce the angle of attack and recover, power use once wing unstalled.
I believe there are even instructors out there who have never done this simple demonstration of how it is the angle of attack you need to reduce.
Next time you are up in a suitable aircraft, above 3000' by a margin:
Try stalling and NOT recovering straight away!
Hold full back stick to keep the aircraft in the stall for as long as you like, keeping wings level with rudder ( or even aileron - give it a go!) until, when you wish to recover, simply move the stick/column forward to reduce the angle of attack and recover, power use once wing unstalled.
I believe there are even instructors out there who have never done this simple demonstration of how it is the angle of attack you need to reduce.
Moderator
Following up on Centaurus's post to clarify a few points ...
(a) C172 TCDS
(b) a quick read through the TCDS, for the earlier models (the later examples are left for others to decipher), suggests that the certification basis was CAR 3
(c) the relevant flight test guidance material has been published in various documents over the years and I'll leave it to you to track them down .. for this discussion the regs give enough information
(d) certification stall recovery requirements haven't changed all that much over the years.
If we go back as far, say, as CAM3 (that's older than I am) the words are
During the recovery portion of the maneuver, it shall be possible to prevent more than 15 degrees roll or yaw by the normal use of controls, and any loss of altitude ill excess of 100 feet or any pitch in excess of 30 degrees below level shall be entered in the Airplane Flight Manual.
and, if we jump ahead, say, to the present FAR 23
During the entry into and the recovery from the maneuver, it must be possible to prevent more than 15 degrees of roll or yaw by the normal use of controls except as provided for in paragraph (e) of this section [para (e) is not relevant to this discussion]
(e) what that means is that the test program very likely used whatever aileron was needed to constrain roll to not more than the specified 15 degrees. Depending on which particular set of rules might be pertinent, this can be ruthlessly anticipated.
(f) if one uses the typical pilot training stall recovery (which has nothing to do with certification thinking and is of rather questionable parentage) one ought not to be surprised when/if one finds oneself on one's back with a good view of the heavens ...
Hold full back stick to keep the aircraft in the stall for as long as you like
Now, that's quite at variance with the certification requirements and expectations. Don't be surprised if you get bitten on the tail from time to time ...
keeping wings level with rudder
Potentially dangerous - rudder and spins tend to go together.
The certification expectation is that rudder is used to maintain heading, ie constrain yaw excursions
(a) C172 TCDS
(b) a quick read through the TCDS, for the earlier models (the later examples are left for others to decipher), suggests that the certification basis was CAR 3
(c) the relevant flight test guidance material has been published in various documents over the years and I'll leave it to you to track them down .. for this discussion the regs give enough information
(d) certification stall recovery requirements haven't changed all that much over the years.
If we go back as far, say, as CAM3 (that's older than I am) the words are
During the recovery portion of the maneuver, it shall be possible to prevent more than 15 degrees roll or yaw by the normal use of controls, and any loss of altitude ill excess of 100 feet or any pitch in excess of 30 degrees below level shall be entered in the Airplane Flight Manual.
and, if we jump ahead, say, to the present FAR 23
During the entry into and the recovery from the maneuver, it must be possible to prevent more than 15 degrees of roll or yaw by the normal use of controls except as provided for in paragraph (e) of this section [para (e) is not relevant to this discussion]
(e) what that means is that the test program very likely used whatever aileron was needed to constrain roll to not more than the specified 15 degrees. Depending on which particular set of rules might be pertinent, this can be ruthlessly anticipated.
(f) if one uses the typical pilot training stall recovery (which has nothing to do with certification thinking and is of rather questionable parentage) one ought not to be surprised when/if one finds oneself on one's back with a good view of the heavens ...
Hold full back stick to keep the aircraft in the stall for as long as you like
Now, that's quite at variance with the certification requirements and expectations. Don't be surprised if you get bitten on the tail from time to time ...
keeping wings level with rudder
Potentially dangerous - rudder and spins tend to go together.
The certification expectation is that rudder is used to maintain heading, ie constrain yaw excursions
