Special Flight Rules Area

In United States aviation, a special flight rules area (SFRA) is a region in which the normal regulations of flight do not apply in whole or in part, especially regulations concerning airspace classification, altitude, course, and speed restrictions, and the like.

Following the terrorist attacks of September 11, 2001, the airspace around Washington DC underwent a number of changes designed to restrict flying around the city. In 2003, a temporary flight rules area was created and was named the Washington DC Air Defense Identification Zone. In 2008 the temporary status of the ADIZ was removed and the rule was made permanent.

In order to fly within the DC SFRA, pilots of general aviation aircraft are required to file a special fight rules flight plan, obtain a discrete transponder code, and remain in contact with air traffic control at all times. Special training is required in order to fly within 30 nm of the Washington DC (KDCA) VOR.

Long established in the Los Angeles basin is the Los Angeles SFRA. Los Angeles International Airport is surrounded by extensive Class B airspace, which is difficult for VFR traffic to navigate. In particular, the airport has four large runways running east/west that have airspace protection from 10,000 feet down to the surface that is 25 statute miles wide. This large swath of Class B airspace bisects Los Angeles and makes flights between the airports north of LAX and south of LAX require air traffic control to route these flights. To alleviate this load on ATC, the SFRA over LAX defines two exceptions to the Class B airspace to allow VFR aircraft to transit without control from ATC.

There are two routes, one for southeast-bound traffic and one for northwest-bound traffic. Both follow the 132° radial of the Santa Monica VOR between the Santa Monica Airport and the intersection of Interstate 405 and Imperial Highway. Southeast-bound traffic flies at 3,500 feet. Northwest-bound traffic flies at 4,500 feet. Despite being in the Class B airspace, aircraft following the rules of this corridor need not communicate with ATC.

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