Which term describes the condition of the rotor blade when operating at an angle of attack greater than the maximum angle of lift?

Which term describes the condition of the rotor blade when operating at an angle of attack greater than the maximum angle of lift?

• A. Blade Stall
• B. Blade Track
• C. Blade Lead or Lag
• D. Blade Tip

Answer: (A)

Blade stall is the situation where a rotor blade’s angle of attack exceeds the maximum lift angle, causing the airflow to separate from the blade surface. When that happens, lift on the blade drops off sharply while drag increases, so the rotor loses some of its authority and the flight characteristics can become unstable. In practice, you’d reduce collective to lower the blade pitch and the angle of attack, allowing the airflow to reattach and the rotor to regain smooth, usable lift. The other terms refer to different aspects of blade motion or features and don’t describe this aerodynamic stall.

Blade stall is the situation where a rotor blade’s angle of attack exceeds the maximum lift angle, causing the airflow to separate from the blade surface. When that happens, lift on the blade drops off sharply while drag increases, so the rotor loses some of its authority and the flight characteristics can become unstable. In practice, you’d reduce collective to lower the blade pitch and the angle of attack, allowing the airflow to reattach and the rotor to regain smooth, usable lift. The other terms refer to different aspects of blade motion or features and don’t describe this aerodynamic stall.