How many blades does the tail rotor feature?

• A. 3 semi-rigid blades
• B. 2 semi-rigid blades
• C. 4 fully articulated blades
• D. 1 rigid blade

Answer: (B)

The tail rotor of the TH-73 features 2 semi-rigid blades. This design is an important aspect of the helicopter's overall performance and stability. The semi-rigid configuration allows the blades to flap and feather, which provides better control and reduces the risk of excessive vibration. The use of two blades strikes a balance between weight and performance, which is essential for training operations where maneuverability and responsiveness are key.

In other designs, such as fully articulated rotors or having more blades, you might see variations aimed at improving lift or handling characteristics, but in the case of the TH-73’s tail rotor, the choice of two semi-rigid blades effectively meets the necessary design requirements for stability and control in a training environment.