Even today there are lot of misconception about how and WHY static pressure reduce above wing. 1)Faster air velocity cause low static pressure One involves holding a piece of paper horizontally so that it droops downward and then blowing over the top of it. As the demonstrator blows over the paper, the paper rises. It is then asserted that this is because "faster moving air has lower pressure" One problem with this explanation can be seen by blowing along the bottom of the paper: were the deflection due simply to faster moving air one would expect the paper to deflect downward, but the paper deflects upward regardless of whether the faster moving air is on the top or the bottom.Another problem is that when the air leaves the demonstrator's mouth it has the same pressure as the surrounding air; the air does not have lower pressure just because it is moving; in the demonstration, the static pressure of the air leaving the demonstrator's mouth is equal to the pressure of the surrounding air.A third problem is that it is false to make a connection between the flow on the two sides of the paper using Bernoulli’s equation since the air above and below are different flow fields and Bernoulli's principle only applies within a flow field. 2) Curved airflow above wing cause low static pressure Why curved airflow cause low in pressure? Because of centrifugal force make air molecules far appart so pressure drop or? 3) Why air follow curved wing surface insted goes in straight line? Is reason for that visocsity which "stick" air to the surface or high ambinet pressure above wing push low pressure in to upper wing surface?