Results from a rapid decrease in lift caused by the separation of airflow from the wing's surface brought on by exceeding the critical angle of attack.

Results from a rapid decrease in lift caused by the separation of airflow from the wing's surface brought on by exceeding the critical angle of attack.

• A. Stall
• B. Flutter
• C. Buffet
• D. Mach tuck

Answer: (A)

Stall happens when the angle of attack goes beyond the critical value, so the airflow can no longer stay attached to the wing. The boundary layer separates, creating a large, turbulent wake and causing lift to drop rapidly while drag increases. This abrupt loss of lift is the defining feature of stall and occurs because the flow cannot follow the wing’s surface at high angles. Flutter, by contrast, is a structural–aerodynamic vibration that develops from aeroelastic interaction; buffet is the unsteady pressure fluctuations and vibrations caused by separated flow (often associated with stall but not the same instantaneous lift loss mechanism); Mach tuck is a transonic phenomenon where a shock-induced shift in the center of pressure produces a nose-down moment. So the described rapid lift decrease due to flow separation at a high angle of attack is stall.

Stall happens when the angle of attack goes beyond the critical value, so the airflow can no longer stay attached to the wing. The boundary layer separates, creating a large, turbulent wake and causing lift to drop rapidly while drag increases. This abrupt loss of lift is the defining feature of stall and occurs because the flow cannot follow the wing’s surface at high angles.

Flutter, by contrast, is a structural–aerodynamic vibration that develops from aeroelastic interaction; buffet is the unsteady pressure fluctuations and vibrations caused by separated flow (often associated with stall but not the same instantaneous lift loss mechanism); Mach tuck is a transonic phenomenon where a shock-induced shift in the center of pressure produces a nose-down moment. So the described rapid lift decrease due to flow separation at a high angle of attack is stall.