Expert: Jeff Davis - 7/26/2007

Question
my question is several times i seen passenger flights are still on the air...without moving i mean totally stop  moving... especially in the airport area its like waiting for something like signal... is it possible for a passenger flight can stop the moving on the air i am expecting a brief reply how it is?

Answer
What you have seen is an optical illusion; that is, what your eye perceives is different from what is actually happening.  An object as large as a passenger airplane sometimes appears to be moving very slowly, or even stopped, especially if its movement is directly toward you or away from you.  If the airflow over the wings is less than about 120 miles per hour, the wings won't generate enough lift to keep the airplane in the air.  The only way the airplane can actually stop in the air is if there is a headwind equal to the airspeed of the airplane; you can actually do this with a smaller, slower plane on a windy day, but it doesn't happen with faster airplanes such as the airlines use.  Thank you for the interesting question.