The General Dynamics F-111 "Aardvark" is a medium-range interdictor and tactical strike aircraft that also fills the roles of strategic bomber, reconnaissance, and electronic warfare in its various versions. Developed in the 1960s and first entering service in 1967, the United States Air Force (USAF) variants were officially retired by 1998. The Royal Australian Air Force (RAAF) is the sole remaining operator of the F-111.

The F-111 pioneered several technologies for production military aircraft including variable-sweep wings, afterburning turbofan engines, and automated terrain following radar for low-level, high-speed flight. Its design was influential, being reflected in later Soviet aircraft such as the Sukhoi Su-24, and some of its advanced features have since become commonplace.

The F-111 is an all-weather attack aircraft capable of low-level penetration of enemy defenses to deliver ordnance on the target.

The F-111 features variable geometry wings, an internal weapons bay and a cockpit with side by side seating. The cockpit is part of an escape crew capsule. The wing sweep varies between 16 degrees and 72.5 degrees (full forward to full sweep).

The aircraft is powered by two Pratt & Whitney TF30 afterburning turbofan engines. The F-111's variable geometry wings, escape capsule, terrain following radar, and afterburning turbofans were new technologies for production aircraft.

Although conceived as a multi-role fighter, the F-111 became a long-range attack aircraft primarily armed with air-to-surface ordnance.

Weapons bay

The F-111 has an internal weapons bay under the fuselage for various weapons.

• Cannon: All tactical combat versions (that is, not the EF-111A or FB-111A/F-111G) could carry a single M61 Vulcan 20 mm cannon with a very large (2,084 round) ammunition tank, covered by an eyelid shutter when not in use.
• Bombs: The bay can alternately hold two conventional bombs, usually the Mk 117 type of nominal 750 lb/340 kg weight, or the Mk 118 (3,000 lb/1,400 kg).
• Nuclear weapons: All F-111 models except the EF-111A and the Australian F-111C were equipped to carry various free-fall nuclear weapons: tactical models generally carried the B43, B57 or B61. The FB-111A was a dedicated nuclear bomber for most of its life, and carried all of those weapons just mentioned, as well as the B83 and the AGM-69 Short Range Attack Missile. The FB-111A could carry one or two AGM-69 SRAM nuclear missiles in its weapons bay and up to four SRAMs on external wing pylons.

Sensor pod: The F-111C and F-111F were equipped to carry the AN/AVQ-26 Pave Tack targeting system on a rotating carriage that kept the pod protected within the weapons bay when not in use. Pave Tack is a FLIR and laser rangefinder/designator that allows the F-111 to designate and drop laser-guided bombs.

· Missiles: The F-111B was intended to be capable of carrying two AIM-54 Phoenix air-to-air missiles in the bay. General Dynamics trialed an arrangement with two AIM-9 Sidewinders carried on rails in a trapeze arrangement from the bay.