What is the critical angle of attack?

The critical angle of attack is specifically defined as the angle at which the airflow over the wing begins to separate, leading to a decrease in lift and the potential occurrence of a stall. As an aircraft approaches this angle, the lift generated by the wing begins to diminish because the smooth airflow over the wing is disrupted, resulting in a turbulent wake behind the wing. Once this separation occurs, the lift is significantly reduced, which can lead the aircraft to lose altitude or stall if corrective actions are not taken.

This concept is vital for pilots and aeronautical engineers because it plays a crucial role in flight safety and performance. Understanding the critical angle of attack helps pilots maintain control during flight maneuvers, ensuring that they operate within safe limits to avoid stalls.

Other options do not accurately define the critical angle of attack. For example, while the angle at which an aircraft begins to climb or the angle at which lift equals weight are important concepts in flight dynamics, they do not specifically relate to the phenomena of airflow separation and stall conditions. The angle at which a plane can no longer gain altitude, while relevant to overall flight performance, also does not capture the essence of the critical angle where stall occurs.