FAA Private Pilot Helicopter (PRH)Performance and LimitationsMedium
During a hovering takeoff into a steady 15-knot headwind, compared to a no-wind hover at the same gross weight and density altitude, the power required to hover will
- Aremain exactly the same
- Bincrease, due to increased translational lift demand
- Cdecrease, because the headwind provides some translational lift
- Ddecrease only if the wind is gusty
Show answer & explanationAnswer & explanation
Correct answer: C. decrease, because the headwind provides some translational lift
A steady headwind during hover provides some of the benefits of translational lift by moving relatively undisturbed air across the rotor disk, which increases rotor efficiency and reduces the power required to maintain a hover compared to a calm-wind hover.
Why the other options are wrong
- A. Power required does change with wind; it is not unaffected.
- B. A headwind reduces power required, it does not increase it.
- D. Gusty wind can actually make hover control more difficult, not more efficient; steady wind provides the benefit.
Wind Effect on Hover Performance
A steady headwind during hover reduces power required by providing translational-lift-like airflow over the rotor disk, improving rotor efficiency.
- Headwind reduces power required to hover
- Effect is similar to effective translational lift
- Tailwinds and gusty/turbulent winds can degrade hover performance and control
Memory trick: A friendly headwind does some of the rotor's work for free.