In aerodynamics, interference drag is a component of parasitic drag which is caused by vortices. Whenever two surfaces meet at a sharp angle on an airplane, the airflow has a tendancy to form a vortex. Accelerating the air into this vortex causes drag on the plane, and the resulting low pressure area behind the plane also contributes. Thus, the primary method of reducing interference drag is eliminating sharp angles by adding fairings which smooth out any sharp angles on the aircraft. As with other components of parasitic drag, interference drag follows the drag equation and rises with the square of the velocity.
Example Usage of Interference
DashTreyhorn: I got hit with a pass Interference call on the way into the office this morning. Those MNF officials aren't playing around, son.
cfiltz: The Packers had to have paid off the refs last night. They did all but shoot those guys on pass Interference and were never called on it.
SouthCentralpar: True/love needs Interference,/a certain blizzard distance,/for the words to worm through. http://tiny.cc/1sg6D RT @poetrymagazine
