The General Dynamics F-111 Aardvark first entered service with the 428th Tactical Fighter Squadron (TFS) at Nellis Air Force Base (AFB) on April 28th 1968. When the 428th sent F-111As to Vietnam for the Combat Lancer program the squadron was still in training at Nellis. Three of those initial six F-111As were lost in Vietnam- all due to horizontal stabilizer malfunctions and not due to enemy action.
The F-111A was the first production aircraft to integrate variable sweep wings into its design. Many more similar designs would follow. The F-111 was powered by the first afterburning turbofan engines. Those engines, the Pratt & Whitney TF30 turbofans, would power only two other American aircraft: The Grumman F-14A Tomcat (with afterburner), and the Vought A-7A/B/C Corsair II (without afterburner).
Another ground-breaking feature of the F-111A crew escape module. Rather than traditional ejection seats, the F-111A was designed with a jettisonable cabin. The cabin was designed to be separated from the jet by rocket thrust. The cabin would then descend under a large parachute. Airbags were used to cushion the landing and would float the module if it came down in water.
The F-111A was designed with an internal weapons bay that could carry bombs, auxiliary fuel tanks, or an M61 Vulcan 20 millimeter rotary cannon. Though the gun was seldom mounted, it gave the F-111A a fearsome ground attack weapon. Much more commonly carried were the auxiliary fuel tanks. External ordnance was carried on four underwing pylons. The inside pylons were capable of swiveling to remain lined up with the fuselage when the wings sweep was changed. The outer pylons were fixed.
The F-111A’s ability to penetrate low and fast was provided by a new generation of avionics. The General Electric AN/APQ-113 attack radar was connected to a Texas Instruments AN/APQ-110 terrain following radar, both in that distinctive nose, and a Litton AJQ-20 inertial navigation and navigation attack system. These black boxes gave the F-111A its hands-free low-level flight capability.
The F-111B was to be the Navy’s fleet air defense fighter aircraft. General Dynamics teamed with Grumman to adapt the F-111A for the Navy’s needs. Sporting a shorter nose and an arresting hook, the B was plagued by development problems and was never going to be able to operate in the harsh world of carrier aviation. Then the Navy changed their requirements for the new fighter, particularly those governing maneuverability. In the end the Navy ended up with a TF30-powered, swing-wing fighter anyway…the F-14A Tomcat.
F-111 development continued. The next major variant of the design was the F-111C for the Royal Australian Air Force (RAAF). The F-111C was basically an A with longer B wings and strengthened landing gear. The Aussies flew 24 F-111Cs, calling them Pigs, between 1973 and 2010. They also operated an additional 15 F-111G models between 1993 and 2007. The RAAF replaced their F-111s with Boeing F/A-18F Super Hornets. When the Pigs were retired at the end of 2010 the RAAF simply buried them in a landfill.
Next up was the F-111D for the Air Force. This variant was essentially an F-111A equipped with Mark II avionics, uprated TF30 engines fed by improved air intakes, and some of the first “glass” display screen cockpits in the Air Force. Equipping only the 27th Tactical Fighter Wing (TFW) at Cannon AFB in New Mexico, the F-111Ds had some initial avionics reliability issues. Microprocessors were brand new back then and it took a while before the Air Force sort of pulled the plug on figuring out the D, retiring them somewhat prematurely in 1991-1992.
The F-111E was an interim variant that incorporated the improved Triple Plow II boundary layer control engine air intakes but retained the same TF30 power plants as the F-111A. There was an improved stores management system and a few other incremental upgrades, and some of the E variants ended up with uprated engines and some avionics upgrades, but the F-111E was a bridge to the next variant of the F-111.
The F-111F was the last variant of the F-111 built for Tactical Air Command (TAC). The Mark IIB avionics suite was more capable with fewer teething problems than the Mark II suite. The F had the improved engine air intakes feeding TF30-P-100 engines, providing a 35% increase in thrust. The F-111F also carried a Pave Tack forward looking infrared (FLIR) and laser target designator system in its weapons bay. The system rotated into a ventral position when in use. Later upgrades included even more powerful TF30 engines and multi-function cockpit displays.
The FB-111A was the first Strategic Air Command (SAC) version of the F-111A. Intended to replace both the Convair B-58 Hustler and the early Boeing B-52 Stratofortress variants, the FB-111A was equipped with yet another avionics suite, this one called the SAC Mark IIB. Also rolled into the FB-111A were strengthened landing gear allowing a heavier max takeoff weight, the popular longer B model wings, a redesigned rear fuselage, and other incremental improvements. A third pylon was added to each wing. FB-111As were retired when the Rockwell B-1B Lancer went into service. Many of the FB-111As were converted to F-111Gs for TAC to use primarily as trainers. Some of them were sold to the RAAF.
The Royal Air Force toyed with the notion of employing the F-111. Their version, dubbed the F-111K, would have been a replacement for the canceled BAC TSR-2 attack aircraft. Ordered in 1967, the F-111K was to be an F-111A with longer F-111B wings, upgraded avionics and British mission-specific systems, the FB-111A landing gear, a refueling probe, and the ability to carry a reconnaissance “pallet” in the weapons bay. The RAF canceled their order in January of 1968 before any F-111Ks were completed. Parts for the F-111K program were diverted to construction of the SAC FB-111As.
The final version of the F-111 was the EF-111A Raven. This tactical electronic warfare version, intended to replace the Douglas EB-66 Destroyer, was equipped with a mission avionics suite developed largely from the avionics found in the Navy’s Grumman EA-6B Prowler. Grumman again partnered with GD to build the EF-111A, which was in general terms a rebuilt F-111A stuffed with black boxes and adorned with a ventral avionics canoe and a dedicated electronic warfare operator position in the cockpit. The EF-111A Spark Varks were the last F-111 variants to be retired by the Air Force on May 2nd 1998 at Cannon AFB.
F-111s were used in combat during Operation El Dorado Canyon and of course during the Gulf War. Their record for going in fast and low and planting their bombs dead on target is the stuff of legends. Lots of times when the public was treated to bomb damage video, that video was captured by the Pave Tack pods on F-111Fs. The Air Force officially retired the last operational F-111Fs on July 27th 1996. It was not until that day that the Air Force officially recognized the nickname of Aardvark for the F-111. They were replaced by McDonnell Douglas (Boeing) F-15E Strike Eagles.