How far can mechanical turbulence extend downwind of an object?

Mechanical turbulence caused by an object in the wind, such as a building or mountain, can significantly affect the airflow in its vicinity. When wind encounters an obstacle, it generates turbulence that can extend downwind. The generally accepted range for this turbulence to persist is approximately 7 to 10 times the height of the object. This range takes into account the way winds interact with the object, causing changes in velocity and direction that result in a disturbed airflow pattern.

The turbulence will be most pronounced right at the object's height and gradually decrease as one moves further away. Understanding this principle is crucial for pilots to anticipate and respond to changes in flying conditions, particularly when flying near large obstacles where turbulence may lead to difficult handling characteristics. Thus, recognizing that turbulence can extend 7 to 10 times the height of an obstruction helps pilots in making safer flying decisions.