Picture of the Day: The Vapor Cone
THE VAPOR CONE
An F-16 Fighting Falcon pilot with the Viper East Demonstration Team from Shaw Air Force Base, S.C., creates a ‘cone’ of condensation on Aug. 21, 2010, as he nears Mach 1 during a flyby at an open house at Volk Field Air National Guard Base.
The ‘cone’ of condensation is known as a vapor cone, or shock collar or shock egg. The phenomenon is frequently encountered at high-subsonic Mach numbers, but can also occur in lower-speed conditions, such as high-g maneuvers by fighter aircraft. The cloud is caused by extremely low pressure in an ‘expansion region’ of the airflow around the aircraft, usually in relatively humid atmospheric conditions. A common misconception is that this effect is the aircraft ‘breaking the sound barrier’. [Source: Wikipedia]
The Sifter has previously done a feature post on airplanes photographed at supersonic speed. If you enjoyed this photo be sure to check out 40 Pictures of Airplanes Breaking the Sound Barrier