The North American Aerospace Defense Command plans to conduct military training flights starting at midnight tonight over the D.C. area.
Aircraft participating in the flight exercise include Air Force F-16 fighter jets, a Coast Guard MH-65D Dolphin helicopter, an Army C12-V aircraft and Civil Air Patrol Cessna 182T general aviation aircraft.
Some portions of the exercise could involve flights at approximately 2,500 feet and may be visible from the ground.
NORAD routinely conducts exercises with a variety of scenarios, including airspace restriction violations, hijackings and responses to unknown aircraft. All NORAD exercises are carefully planned and closely controlled.
The training flights are being held in coordination with the Federal Aviation Administration.
The flights are expected to continue through about 2:30 a.m.