Animation comparing two aircraft at the same airspeed. One flies with
 the wind and has a higher ground speed. The other flies into the wind.


Button to Display Equal Airspeed Button to Display Equal Ground Speed Button to Display Equal Wind Speed Button to Display Take Off Button to Stop

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 airspeed (160 mph). The top aircraft flies with the 40 mph wind, so its ground speed is 200 mph. (Airpseed = Ground Speed - Wind Speed; 160 = 200 - 40 ). The lower aircraft flies into the 40 mph wind, so its ground speed is only 120 mph. (160 = 120 - (-40) ). More information about these velocities is given on the Relative Velocity Slide.

Button to Display Aerodynamics Index


Go to...

Beginner's Guide Home Page
Learning Technologies Home Page http://www.grc.nasa.gov/WWW/K-12
NASA Glenn Home Page http://www.grc.nasa.gov/
NASA Home Page http://www.nasa.gov/


by Tom Benson
Please send suggestions/corrections to: benson@grc.nasa.gov

Last Updated Thu, Jun 12 04:47:01 PM EDT 2014 by Tom Benson