air sleeve
/ˈɛrˌsliv/
noun
- A fabric tube, open at both ends, mounted on a pole to show the direction and strength of the wind, typically at an airport; a windsock.
- At the small airfield, a bright orange air-sleeve flapped in the breeze.
- The pilot checked the air-sleeve before landing to see which way the wind was blowing.
- The air-sleeve was fully extended, indicating strong winds from the north.