Which term describes the tendency of the helicopter to drift laterally during hover?

Which term describes the tendency of the helicopter to drift laterally during hover?

• A. Translating Tendency
• B. Translational Drift
• C. Lateral Drift
• D. Yaw Tendency

Answer: (A)

Translating tendency is the natural lateral drift a helicopter experiences while hovering when the rotor wash and the wind interact with the airframe. Even with no intentional forward motion, the rotor downwash and the aircraft’s aerodynamics create a small horizontal force that pushes the helicopter to translate in the direction of the relative wind. Because of this, a pilot must use cyclic control to counteract the drift and hold a steady position. This term is the standard way pilots describe and think about that hovering behavior. The other terms describe different ideas. Lateral drift is a descriptive phrase but not the official term used in training. Translational drift (with an extra “al”) isn’t the recognized term in the manuals. Yaw tendency refers to rotation about the vertical axis, not the sideways movement across the hover area. So the best, specific term for this hovering phenomenon is translating tendency.

Translating tendency is the natural lateral drift a helicopter experiences while hovering when the rotor wash and the wind interact with the airframe. Even with no intentional forward motion, the rotor downwash and the aircraft’s aerodynamics create a small horizontal force that pushes the helicopter to translate in the direction of the relative wind. Because of this, a pilot must use cyclic control to counteract the drift and hold a steady position. This term is the standard way pilots describe and think about that hovering behavior.

The other terms describe different ideas. Lateral drift is a descriptive phrase but not the official term used in training. Translational drift (with an extra “al”) isn’t the recognized term in the manuals. Yaw tendency refers to rotation about the vertical axis, not the sideways movement across the hover area. So the best, specific term for this hovering phenomenon is translating tendency.