to measure wind.
This is a windsock.
Windsock
A Windsock is a tube made of cloth usually hung close to runways in airports. It is used to indicate wind direction and speed.In addition to airports, windsocks are also used close to chemical plants, where there is risk of gas leaks. They are also sometimes used close to highways.Wind direction is the opposite direction to which the windsock is pointing. Windspeed is indicated by the windsock's angle to the pole. When the winds are strong, the windsock flies horizontally.It tells which way the wind is blowing. You will usually see them at Airports.
Windsocks can't determine chemical hazards. If your using a windsock at a chemical plant, it would be there to tell you which direction and how strong the wind is blowing. This information can be used to calculate how far and how fast the plume of contaminants will travel. The EPA has several modeling programs that assist in determining the necessary zone of evacuation. This distant varies based on a variety of inputs, as well as day or night. Windsock and generally calibrated to a MPH or KNOT reading. When the sock is full the wind is blowing at 15 MPH. A 27 " long windsock indicates 15 MPH when full extended. Other companies offer micro socks or flags that can detect winds of less then 3 MPH. These would be more useful for on-site use at a chemical plant, as they would give more detailed closer to the ground information. A large windsock would be helpful when the release of contaminants might threaten nearby 5 miles away communities. If the wind is blowing the contaminants at 15 MPH and the town was 10 miles away.....you get the idea.
a windsock from japan
Generally windsock do narrow towards the free end
So the wind passed through and moves the windsock in the direction the wind is blowing.
Wings for Roger Windsock - 1947 was released on: USA: 1947
a Chinese windsock
At airports.
it was invented in 1432
Windsocks are often used at airports to indicate the direction and strength of the wind.A standard windsock has white and orange stripes
It shows wind direction.
a windsleeve, a windcone
No
it shows how hard the wind is blowing