My question is how can the angle of attack be changed when the wing is in the slipstream of a propeller, giving "enough air flow" to the wing. The propeller sends the flow of air in the same direction related to the wing no matter how the aeroplane is oriented in the space. So theoretically the angle of attack should never change.
UPD: The answer should not depend on how the plane is thrusted. Turbo engines are also pushing the plane in the same direction related to the fixed wing. ( I am not talking about engines that can change the vector of thrust).