A sonic boom is the audible component of a shock wave in air.
The term is commonly used to refer to the air shocks caused by the supersonic flight of military aircraft or passenger transports such as Concorde (Mach 2.03, no longer flying) and the Space Shuttle (up to Mach 27). Sonic booms generate enormous amounts of sound energy, sounding much like an explosion; typically the shock front may approach 167 megawatts per square meter, and may exceed 200 decibels.

When an aircraft is near the sound barrier, an unusual cloud sometimes forms in its wake. A Prandtl-Glauert Singularity results from a drop in pressure, because of shock wave formation. This pressure change causes a sharp drop in temperature, which in humid conditions leads the water vapor in the air to condense into droplets and form the cloud.