Which ULY factor is described as winds that increase induced airflow through the fenestron, reducing tail rotor blade angle of attack, and reducing tail rotor thrust?

Which ULY factor is described as winds that increase induced airflow through the fenestron, reducing tail rotor blade angle of attack, and reducing tail rotor thrust?

• A. LEFT CROSS WINDS
• B. WEATHERCOOK STABILITY
• C. COLLECTIVE INDUCED YAW
• D. LOSS OF TRANSLATIONAL LIFT

Answer: (A)

Crosswinds from the left change the airflow through the fenestron and directly affect tail-rotor effectiveness. Winds blowing from the left push more air through the fenestron, increasing the induced (downward) flow the tail rotor sees. That additional inflow lowers the tail rotor blades’ angle of attack for a given blade pitch, so the tail rotor produces less thrust. Since tail-rotor thrust is what provides anti-torque, its reduction alters yaw behavior. The scenario described matches left cross winds, while the other options describe separate aerodynamic or stability effects that don’t involve this increase in fenestron inflow.

Crosswinds from the left change the airflow through the fenestron and directly affect tail-rotor effectiveness. Winds blowing from the left push more air through the fenestron, increasing the induced (downward) flow the tail rotor sees. That additional inflow lowers the tail rotor blades’ angle of attack for a given blade pitch, so the tail rotor produces less thrust. Since tail-rotor thrust is what provides anti-torque, its reduction alters yaw behavior. The scenario described matches left cross winds, while the other options describe separate aerodynamic or stability effects that don’t involve this increase in fenestron inflow.