Obstacle generated ’Curl Over’

What happens to the smooth flowing air as it passes over obstacles on the ground. Hedges, buildings and woodland for example, can produce a turbulence at different heights above the ground. This is often felt by light aircraft particularly. It is common for example to feel an effect on the aeroplanes flight characteristics at heights of about 1000 feet. This is not a worry! In fact it demonstrates the density of the air around us and is why flight is possible at all. It is this dynamic quality dem