Simple Flying - Daniel Wong
Due to the importance of Washington D.C. both symbolically and politically, there are many rules surrounding Washington National Airport.
The most famous rule of Washington National Airport is its perimeter rule. The rule was implemented in 1966 to keep long-haul traffic away from DCA. The original 1966 statute only permitted flights of less than 650 miles (1050 km) to operate. This maximum distance was increased by Congress in the 1980s to 1000 miles (1600 km) and then again to 1250 miles (2010 km). The FAA has, nevertheless, been granting exemptions to different airlines to operate services beyond the perimeter into Washington National.
Following the 9/11 attacks, many flight restrictions were put into effect at Washington National because of its proximity to the seat of American government.
...approach into DCA was limited to a path which follows the Potomac River. Lights have been placed on the bridges along the Potomac to assist pilots in their approach into the airport.