I agree with Lynn. The chart you entered does not really deal with , It
just shows that for the same lift coeff thr lower aspect ratio wing has to operate at a
higher angle of attack (and with increased induced drag) Pitch sensitivity is a very
strong function of Cg, and can be some what mitigated by tail volume coeff. A higher
aspect ratio wing has a narrower allowable Cg range than a low aspect ratio wing, and thus
could be accused of greater pitch sensitivity. The lift slope data can be used in aircraft
design for stability enhancement, and is why most canards have a higher aspect ratio for
the canard than the main wing, and the obverse is true for most conventional planes (ie
the horizontal has a low aspect ratio.

I believe that the military is training stall avoidance, rather than recovery, and
demonstrating that the wing can lift at nearly zero airspeed if you unload it by
trajectory.
Vance

Come on Vance the term "pitch sensitivity" is not to be found anywhere in Von Doenhoff,
Perkins & Hage, Von Mises, Hoerner or any other book I have read on the subject for the
last 55 years. Look in the index. No such term. I have heard of stick force per G.
Are you talking about stick angle verses pitch angle or stick angle verses angle of attack?
We need to use standard nomenclature or we will not be able to communicate
on this subject.

Paul Lamar

The term pitch sensitivity may not be a true technical term, but I bet if you fly a plane with
that characteristic, you will assure us it is a real effect. As I mentioned, the condition that
you would describe by such a term  would generally be the result of an aft Cg, where the slope
of stick force per G ( or stick force versus speed) flattens out, or in worst case reverses to
the point of divergent pitch stability - ie, if the nose drops, and the speed builds up, the
nose down  pitch will increase unless you make a positive control input.  Or worse yet as the
nose rises and the plane slows, it will continue to rise, unless you make a conscious
correction.  As you approach that case the stick forces get lighter, and you are constantly
chasing the airplane in pitch - I think it would be fair to say such an airplane is sensitive in
pitch.

As for the canard stalling before the wing - if that is not a case of insufficient pitch
authority to stall the main wing, I do not know what would be. This is exactly the same as the
Aircoupe. The horizontal cannot make enough downward force to pick up the nose. The end result is
also the same, if you get below that speed while landing, you cannot flare, and a lot of tandem
(near equal area canards) aircraft with wheels at the end have broken the front wing in just
that sort of condition.

If you load the canard aircraft such that the canard does not stall first, you are in at least as
much trouble as an aft Cg conventional design, probably worse because of the "deep stall" non
recoverable modes which have been demonstrated, frequently with loss of life. (Some conventional
planforms have also encountered this situation - one time with the loss of an entire test flight
crew of an airliner prototype, tryiing to regain control for several minutes).
Vance

"if you get below that speed while landing, you cannot flare," 

The opposite of this is if you get beyond normal top speed before a climb 
entry you can stall.

Paul Lamar
 
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