The chart above is plotting the coefficient of lift of a particular wing as its angle of attack increases. Lift will continue to increase until a certain angle of attack called the critical angle of attack. After this point, the wings still create lift, but the amount of lift created is decreased. This is called a stall. When some people think of the word stall, they think about the engines stalling. However, we are talking about an aerodynamic stall which has nothing to do with the engine. Stalls happen when the normally smooth airflow over the wing separates from the wings upper surface, resulting in a turbulent airflow.
The parts of the wing that have turbulent airflow passing around them are not producing any lift. For a given airplane. A stall will always occur at the same angle of attack the critical angle of attack, regardless of its airspeed, attitude or weight. Heroes a wing at normal cruise angle of attack something small like four or five degrees increasing the angle of attack will progressively cause more and more disruption of the airflow on the upper surface of the wing. Early on, the airflow will separate at the trailing edge. As the angle of attack increases, the separation of the airflow moves from the trailing edge of the wing to the leading edge. As this separation occurs, the airflow will become more and more turbulent and less and less lift gets generated.
Different airplanes will exhibit different stall characteristics but generally coincide with mushy sluggish flight control responses, a STA warning horn, a buffeting or shaking feeling of the airplane and pilots controls, and once the stall occurs, the aircraft's nose will pitch down and the aircraft will begin losing altitude. Since the stall is a result of an excessive angle of attack, the only way to recover from a stall is to reduce the angle of attack below the critical angle. Power should be added to minimize the amount of altitude lost in the recovery and increase the airplanes speed as quickly as possible.
The parts of the wing that have turbulent airflow passing around them are not producing any lift. For a given airplane. A stall will always occur at the same angle of attack the critical angle of attack, regardless of its airspeed, attitude or weight. Heroes a wing at normal cruise angle of attack something small like four or five degrees increasing the angle of attack will progressively cause more and more disruption of the airflow on the upper surface of the wing. Early on, the airflow will separate at the trailing edge. As the angle of attack increases, the separation of the airflow moves from the trailing edge of the wing to the leading edge. As this separation occurs, the airflow will become more and more turbulent and less and less lift gets generated.
Different airplanes will exhibit different stall characteristics but generally coincide with mushy sluggish flight control responses, a STA warning horn, a buffeting or shaking feeling of the airplane and pilots controls, and once the stall occurs, the aircraft's nose will pitch down and the aircraft will begin losing altitude. Since the stall is a result of an excessive angle of attack, the only way to recover from a stall is to reduce the angle of attack below the critical angle. Power should be added to minimize the amount of altitude lost in the recovery and increase the airplanes speed as quickly as possible.