Duke Field (IATA: EGI, ICAO: KEGI, FAA LID: EGI), also known as Eglin AFB Auxiliary Field #3, is a military airport located three miles (5 km) south of the central business district of Crestview, in Okaloosa County, Florida, United States.

Shortly after the end of World War II, the field was one of several sites used in the production of the 1949 feature film Twelve O'Clock High.

In the 1950s, Duke Field became home to the 3205th Drone Group, which operated radio remote-controlled B-17s and F-80s that were used for gunnery and missile practice over the Gulf of Mexico.

They were also used in the nuclear test program by flying the unmanned aircraft through atomic detonation clouds to gather fallout information.

A large hump-backed steel hangar, the "Butler Hangar", 160 feet (49 m) X 130 feet, transported from Trinidad (probably from the former Waller Air Force Base, closed 28 May 1949 due to budget cuts), was erected at Auxiliary Field 3 between 1 April and ~10 July 1950, by personnel of Company 'C', 806th Aviation Engineering Battalion, under Captain Samuel M. Cable, and the men of the 550th Guided Missiles Wing.

Concurrently, the 8,000-foot (2,400 m) runway was widened to 100 feet (30 m) and additional parking ramps were constructed, with 117,327 cubic yards of dirt excavated.

"[7][8] The DPD operated independently of "the organizational structure of the project, in which it had a vital, central role, including air drops to the underground, training Cuban pilots, operation of air bases, the immense logistical problems of transporting the Cuban volunteers from Florida to Guatemala, and the procuring and servicing of the military planes.

"[9] Between August and October 1970, during the Vietnam War, the Joint Contingency Task Group used AFROTC facilities at Duke Field to house US Army Special Forces troops involved in Operation Ivory Coast, a mission to rescue prisoners of war at Sơn Tây, North Vietnam.

Three civilian B-25s in warbird markings re-enacted the training take-off sessions, with personnel from NAS Pensacola as flight deck crew representing that service's contribution to the Tokyo raid.

The installation is named for 1st Lt Robert L. Duke, who died in the crash of a Curtiss A-25A-20-CS Shrike, AAF Ser.

The Duke Field installation is about 12 miles (19 km) north of the Eglin AFB East Gate on State Road 85.

The airfield has its own air traffic control tower, security forces building, Air Force Fire Protection facilities (Fire Station #8), instrument landing system (ILS), TACAN and support infrastructure such as a large flight line/ramp area, hangars, shoppette, self service gas station, hotel service, fitness track, recreational areas, maintenance facilities and other operational and administrative support buildings.