The Air Force defines a flyover as "one straight and level pass of one to four aircraft of the same type from the same military service and not involving aerobatics or aircraft demonstrations" [source: U.S. Air Force]. Sometimes the aircraft may turn around and execute another pass. The planes maintain an altitude of at least 1,000 feet (305 meters), a rule instituted after Sept. 11. But there aren't tricks or other maneuvers performed, so don't expect to see the Thunderbirds or a stunt team as part of a flyover.
A flyover isn't necessarily made up of fighter jets. Helicopters may be used, such as the UH-60 Black Hawk, or a large cargo plane like a C-17 Globemaster III. In fact, someone requesting a flyover can ask for any plane within the military's inventory, though it's not a guarantee that it will be available.
Flyovers have to be carefully timed, usually so that the fighter jets appear just as the national anthem finishes (during the "home of the brave" line). The calculations are all performed on a computer, using GPS coordinates and a target speed. Meanwhile, the planes are in a holding pattern near the event site. When a spotter positioned on the ground gives the command, the planes are off and soar over the event right on cue. The pilots may later appear at the event to be honored in person.
After the planes or helicopters go by, other associated activities may occur, like a parachute drop by the Army Golden Knights Parachute Team.
On the next page, we'll learn what happens when a flyover goes bad, taking a look at a couple of notorious incidents.