America’s Jet Fighter Assassin – F-111 Aardvark
The General Dynamics F-111 Aardvark was developed by General Dynamics in the 1960s as a medium-range interdictor and tactical attack aircraft. The aircraft is also suitable for strategic nuclear ʙᴏᴍʙɪɴɢ , aerial reconnaissance, and as well as electronic ωɑɾʄɑɾε. In 1967, the F-111 Aardvark entered service with the United States Air Force. In 1973, it also entered service with the Royal Australian Air Force.
563 F-111s of all variants were built. After the F-111A, the F-111D and E models upgraded the Aardvark’s electronics and engine inlets, and increased the thrust of the engines. Another variant, the FB-111, was designed as a strategic ʙᴏᴍʙᴇʀ with improved engines, stretched two feet longer to accommodate additional fuel. Seventy-five of these served in Strategic Air Command units.
Design phase The F-111A and B variants used the same airframe structural components and Pratt & Whitney TF30-P-1 turbofan engines. They featured side-by-side crew seating in an escape capsule as required by the Navy. The F-111B’s nose was 8.5 feet (2.59 m) shorter so as to fit on existing carrier elevator decks, and had 3.5-foot-longer (1.07 m) wingtips to improve on-station endurance time. The Navy version would carry an AN/AWG-9 Pulse-Doppler radar and AIM-54 Phoenix missiles. The Air Force version would carry the AN/APQ-113 attack radar and the AN/APQ-110 terrain-following radar and air-to-ground armament. A team of engineers at General Dynamics was led by Robert H. Widmer.
Lacking experience with carrier-based fighters, General Dynamics teamed with Grumman for the assembly and testing of the F-111B aircraft. In addition, Grumman would also build the F-111A’s aft fuselage and the landing gear. The General Dynamics and Grumman team faced ambitious requirements for range, ωεɑρσռs load, and aircraft weight. The F-111 design also included new features on a production military aircraft, such as variable-geometry wings and afterburning turbofan engines.
The F-111A mockup was inspected in September 1963. The first test F-111A was rolled out of Plant 4 of General Dynamics’ Fort Worth, Texas, facility on 15 October 1964. It was powered by YTF30-P-1 turbofans and used a set of ejector seats as the escape capsule was not yet available. The F-111A first flew on 21 December 1964 from Carswell Air Force Base, Texas, U.S. The F-111B was also equipped with ejector seats and first flew on 18 May 1965. Initially there were compressor surge and stall issues in certain parts of the flight regime. NASA, the Air Force, and General Dynamics studies resulted in the engine inlet design being modified in 1965–66, culminating with the “Triple Plow I” and “Triple Plow II” designs. The F-111A achieved a speed of Mach 1.3 in February 1965 with an interim intake design. Cracks in the F-111’s wing attach points were first discovered in 1968 during ground fatigue testing; an F-111 crashed the following year due to this issue.
The attach structure required redesign and testing to ensure adequate design and workmanship. Flight testing of the F-111A ran through 1973.The F-111B was canceled by the Navy in 1968 due to weight and performance issues, along with the need for additional fighter requirements. The F-111C model was developed for Australia. Subsequently, the improved F-111E, F-111D, F-111F models were developed for the U.S. Air Force. The strategic ʙᴏᴍʙᴇʀ FB-111A and the EF-111 electronic ωɑɾʄɑɾε versions were later developed for the USAF. Production ended in 1976, after 563 F-111 aircraft were built.