Air Defense Identification Zone (Washington DC)
An Air Defense Identification Zone (ADIZ) has existed since February 10, 2003, around the Baltimore-Washington Metropolitan Area to restrict air traffic near Washington, D.C.
The ADIZ was established as a precursor to the US invasion of Iraq in 2003. It has been erroneously connected to the September 11 attacks as a temporary measure to prevent further attacks. It was made permanent in 2008.
Despite efforts by the Federal Aviation Administration to inform pilots of the ADIZ, there are still many unauthorized incursions by unsuspecting pilots. A pilot who violates the boundaries may be intercepted by military aircraft and escorted to the nearest airport.
The ADIZ (now known collectively as a Flight Restricted Zone and Special Flight Rules Area) was created by the FAA in response to demands by a working group that became formalized as the National Capital Region Coordination Center. The U.S. Congress has never legitimized these restrictions, and any consideration of opposing the Executive Branch's actions became politically unpalatable in the wake of two mishaps that led to the evacuation of the Capitol. One involved a plane carrying Ernie Fletcher, the Governor of Kentucky, which led to an evacuation in 2004. The other, almost a year later, involved a Cessna 150 flown by a student pilot accompanied by a pilot who was not familiar with the ADIZ rules, using an outdated chart.
The original Washington ADIZ was roughly co-extensive with the Class B airspace around Washington. On August 30, 2007, the dimensions of the ADIZ were changed to a 30-nautical-mile-radius (35 mi; 56 km) circle centered on the Ronald Reagan Washington National Airport (DCA) VOR/DME (located at 38°51′34″N 77°2′11″W / 38.85944°N 77.03639°W), with a small triangular cutout for Leesburg Executive Airport (JYO). This change reduced the size of the ADIZ by 1,800 sq mi (4,700 km2) and removed 33 airports from its coverage.
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