The main function of the airport wind cone (also known as wind bag, wind bag) is to visually indicate the ground wind direction and wind speed, provide real-time meteorological information for pilots, ground crew and tower, and ensure the safety of aircraft take-off and landing and ground operations. The specific functions are discussed with you in the article.
The Functions of The Airport Wind Cone
- 1. Indicate wind direction
The open end of the airfield wind vanes points to the direction of the wind (that is, the direction from which the wind blows), and the tail flutters with the wind. For example, if the wind bag points to the north, it means that the current wind is north.
Pilots can adjust the take-off and landing direction according to the wind direction (take off and land against the wind to increase lift), and ground crew can also arrange the use of the runway accordingly.
- 2. Estimation of wind speed
By observing the fluttering angle and fullness of the wind vane, the wind speed can be roughly judged:
Horizontal fluttering: The wind speed is large (usually ≥15 knots, about 28 kilometers/hour).
Half-filled: Medium wind speed (about 515 knots).
Natural droop: The wind speed is low (<5 knots) or there is no wind.
Wind vane at some airports are marked with stripes or colors to help quantify wind speed (e.g., each stripe represents 5 knots).
- 3. Assisting low-visibility operations
At night or when visibility is poor, wind cones are usually equipped with lighting (such as white or orange lights) to help pilots identify wind direction.
- 4. Runway selection decisions
The tower and pilots will choose the runway closest to the headwind based on the real-time data of the wind cone (taking off and landing against the wind can shorten the aircraft’s taxiing distance and improve safety).
- 5. Simple tools for general aviation & small airports
Small airports or temporary runways may lack automatic weather stations. Wind cones are low-cost, reliable backup equipment that provides key meteorological information.
Standards for Wind Vane
According to the recommendations of the International Civil Aviation Organization (ICAO), the airport wind cone is usually 3.6 meters long and 0.9 meters in diameter. It needs to be installed in a conspicuous and unobstructed location near the runway.
Relationship with meteorological instruments: Although modern airports are equipped with electronic wind direction and anemometers, airport wind cones are still an important backup that is intuitive and does not require electricity. By using wind vanes, aviation personnel can quickly respond to weather changes, reduce the risk of crosswind takeoff and landing, and ensure flight safety.
