õhuavad

õhuavad refers to a type of observation system used for determining wind direction and speed. The system is of Estonian origin.

õhuavad relies on lamps that are mounted on a rotating column, with the lamps being adjusted to create shadows when viewed from a specific distance. By observing the direction of the shadows, one can infer the direction from which the wind is blowing.

As part of the system, users also maintain a log of the wind speed based on the rotation of the lamps at set intervals. The intervals are typically standardized to ensure consistent and accurate readings.

õhuavad was an essential tool for sailors and marine users, providing critical data about wind direction before the invention of modern anemometers. It allowed for in-situ wind measurements, ultimately aiding navigators in making informed decisions while at sea.