relatively small fraction of the total weight of the airplane in the
first place, less than 10% in at least some cases, perhaps most
cases)

Lift in a 10 degree climb should be reduced about 1.5%.

I'm not sure your theory holds up very well.

"His" theory is mentioned in a number of aerodynamics books.

Although I agree that a small increase in AOA would not contribute
enough vertical component of lift to overcome the initial increase in
induced drag, there are ways to get into this regime of flight. If
you had enough unused AOA left to generate a load factor, you could
change the flight path then return the AOA to its original value. The
aircraft may be able to stay on a steeper flight path due to the
reduced parasite drag and reduced effective weight. Don't forget that
thrust will increase slightly with a lower airspeed.

To have a vertical component high enough to support the airplane
will require a horizontal component so high that the airplane won't
slow.

Not really clear on what you mean by that. The only component of
thrust that accelerates the airplane is that parallel to the flight
path. If the angle of climb remains the same, then increasing thrust
will obviously accelerate the airplane. However, as thrust increases,
the angle of climb increases up to the point that the component of
aircraft weight along the flight path is equal to the increase in
thrust.


Of course, to me the biggest problem intuitively with your theory is
that I am sure that aerodynamics involves only continuous functions.
Given that, if you assume more than one steady state, you are claiming
that there are multiple local minima/maxima between which are
apparently "lower efficiency" areas. And of course, if there's more
than one, I see no reason to believe that there are only two. This
would then imply that the flight envelope has numerous of these local
minima/maxima points.

All of the above is very vague. What I hear you say is "I don't want
to believe you." ;-)

There are an infinite number of steady states; every time I move the
elevator, I create a new steady state.

Given that in more than 100 years of study, this concept has never
shown up

I doubt you're familiar with even 1% of the 100 years of aerodynamic
research and thought. I'm certainly not.

You should realize that "I've never heard of it so it must be false"
is a weak argument.

Lift is always generated perpendicular to the wing's chord.

No, for subsonic flight, it's perpendicular to the *local* relative
wind, the relative wind that is modified by wingtip vortices. If lift
were perpendicular to the chordline, you would have induced drag in a
wind tunnel, and you don't.

you cannot avoid the fact that when you change the angle of the lift
vector, the portion of the force created by the wing used to
counteract gravity is also changed.

This is based on your mistaken notion above.

Since the lift vector points slightly aft in level flight,

Only because of induced drag.

However, in gliding flight, the vector is pointed forward, helping
counteract the contribution drag makes to lift.

No, the lift vector is perpendicular to the local relative wind
causing it. There is a rearward component (called "induced drag"),
but there is no component forward along the flight path.