OK, I think Iknowthe source of controversy now. A wing doesnot hunt for anangle of attack with noregard to the other forces acting on the body of the airplane. All the forces acting on the plane must be in equilibrium.I often draw asketch called a free body diagram which displays every force and acceleration acting on an object. That way nothing gets missplaced or forgotten.</p>

If we consider a typical airplane in profile view there would bea weight vector (mg), the lift vector (L), the engine thrust vector (T), a drag vector (D), and possibly a stabilizer negative lift vector (S). All these forces (actually it's their moments) will be in equilibrium when the plane is flying or an acceleration must occur (a pitch rotation).</p>

Rapid gain in altitude with throttle setting indicates that when all the other forces are in equilibrium the wing is at an AOA that generates lift in excess of mg. When incidence is reduced, the planes wing will fly at a slightly reduced AOA at the same speed as before. With less AOA there is less Cl and less lift.</p>

For a moment lets suspend the reality and assume a wing "decides" itsAOA. A trainer with 2 degrees downthrust and +2.5 wing incidence ballons in altitude with increase in airspeed.Now wereducewing incidence (<u>relative to our datum</u>) from +2.5 down to 0. The wing now "causes"the plane to fly at a +2.5 higher AOAat every speed. This implies that now the stab is flying 2" lowerbut not generating any positive liftfor some reason and the engine is higherwhich "somehow" appliesa +0.5 upthrust even though the thrust direction and moment arm have not changed with respect to the airplanes center of mass. If an airplane does that I'll eat my hat.

OK, back to reality.

The wing AOAis a committee decision between stab lift, engine thrust and to a small extent cg because its usually slightly ahead of the neutral point. All these players cause torque reactions that find equilibrium and determine the wing AOA. The wing has virtually no power in deciding it's own AOA because it's lift and drag vectors are so close to the cg that their moment arms are very short.

An example. To trim an airplane that gains altitude what do we do? Put in a click of down elevator right? This changes the camber of the stab creating slightly more lift, creating a slight pitch rotation to it's new equilibrium, which changes the AOAof the wing, which causes it to generate slightly less lift.

Buzzard, the reason it took me 4 tries reading your post is because it was soarticulate and confident and yet completely wrong I thought Ihad to bemissing something. Sorry to be harsh but it was you who "contradicted" me withthis same homespun mythology in another thread while I was in the middle of helping a guy correct an incidence problem. Your post threw the entire thread into confusion andkinda pulled the rug out from under my cred. Next time you do that make sure you're right first ok? There's a sticky at the top of this forum called "Good Reading". Check it out.</p>