Windsock

A conical fabric tube mounted on a pole at an airport that visually indicates the wind direction and approximate speed. The windsock points in the direction the wind is blowing toward (downwind), so a pilot determines headwind direction by looking at where the sock is pointing from. A fully extended windsock indicates winds of approximately 15 knots or more. Windsocks are typically located near the runway and are visible from the traffic pattern.