Headwind component

Headwind component is the portion of wind blowing opposite the aircraft's direction of travel or the runway heading. It is normally expressed in knots. A headwind component reduces groundspeed for a given airspeed and can change takeoff and landing performance compared with calm-wind conditions.

How it works

The component depends on wind speed and the angle between the wind direction and the aircraft or runway heading. Wind directly aligned with the nose produces a headwind component equal to the wind speed. Wind at 90 degrees produces no headwind component, although it produces a crosswind component.

Wind reports describe the direction the wind comes from. The crosswind calculator uses the runway heading and reported wind direction to separate the wind into headwind, tailwind, and crosswind components.

Example

A runway heading is 090° and the wind is from 120° at 20 knots. The wind is 30 degrees to the right of the runway, so the headwind component is about 17.3 knots. The remaining component is lateral rather than directly along the runway.

Why it matters

A headwind component can lower takeoff and landing groundspeed and affect runway distance. It also changes the relationship between true airspeed and groundspeed during cruise. The calculated component does not account for every performance factor, including gust spread, runway slope, surface condition, aircraft weight, and technique.

Compare the result with the aircraft's POH or AFM charts and current wind information. The result supports planning and training only.

Related terms and tools

• Crosswind component
• Tailwind component
• Crosswind calculator