USAF Lt. Colonel Brian Bishop (#1 Commander/Leader), Major Bradley Bartels (#2 Left Wing), Major Robert Givens (#3 Right Wing), and Major Paul Krause (#4 Slot) perform an Arrowhead Loop <=
The USAF Thunderbirds are flying the #1-4 F-16C 'Falcons'.
The Arrowhead involves maneuvers in tight formation with as little as 18 inches fuselage to canopy separation. They perform formation loops and rolls or transitions from one formation to another. All maneuvers are performed at speeds of 450 to 500 mph.
The #4 slot pilot flies as close as 18 inches to the commander, #1, during the arrowhead loop.

Photo by Bob Nelson on Sunday, August 30, 1998 at the Grand Forks Air Force Base.