Here's a page for you to explore the relative velocity between an aircraft in flight, the ground, and the air through which the airplane moves. In this animation, the white clouds move relative to the ground at the wind speed, the airplane moves relative to the ground at the ground speed, and the airplane moves relative to the air at the airspeed. Airspeed is the important velocity for the generation of lift and drag. Notice that both aircraft have the same wind speed (40 mph). The top aircraft flies with an airspeed of 160 mph , so its ground speed is 200 mph. (Airpseed = Ground Speed - Wind Speed; 160 = 200 - 40 ). The lower aircraft flies with an airspeed of 240 mph, so its ground speed is 280 mph. (240 = 280 - 40 ). More information about these velocities is given on the Relative Velocity Slide.
Last Updated Thu, Jun 12 04:47:01 PM EDT 2014
by Tom Benson