Originally Posted by
698jet
Would a wing with flaps extended stall at a lower or a higher angle of attack than the same wing with flaps retracted ?...
The lift versus AoA curve goes up and to the left. So, stalling AoA goes down by a few degrees with flaps. The additional lift we get is far stronger than a lowered critical AoA, which is why we use flaps.
Denker on flaps
Someone said AoA tends to remain constant when flaps are deployed: not correct. If this were true airplanes would be crashing practically every time someone deployed the flaps at too slow a speed. Many small airplanes employ the last ten to thirty degrees of flaps on short final. Typical trainers balloon a little from the extra lift when the flaps go out, then they quickly go nose down without any help from the pilot to reach a new equilibrium between lift and weight. Obviously, the weight of the airplane stays the same. The wing wants to go to a lower AoA which also helps to maintain a safe stall margin. The airplane also tends to trace a lower glide path because of extra drag which helps in short field performance and obstacle clearance.
...and if both wings were at the same angle of attack which would produce more lift ?...
Again, the curve goes left and up. You decide- draw it on paper if it helps.