What Is the "Sound Barrier"?

The first airplanes to approach the speed of sound encountered a number of unexpected conditions: sharply increased drag, violent shaking of the airplane, and loss of lift and control. Airplanes that approached this threshold often broke apart and crashed, as though there existed a "sound barrier"--a speed limit that could not be broken.

The sound barrier proved to be a myth. Thanks to powerful engines and design features that minimize drag, airplanes now routinely fly faster than the speed of sound.

(Rev. 09/17/96)