The nose of F-111B was 2.59m shorter than the first variant and featured 1.07m longer wingtips. "Two F-111 variants, F-111A and F-111B were initially developed for the USAF and US Navy respectively." General Dynamics collaborated with Northrop Grumman for designing the fuselage, landing gear and assembly and test of the aircraft. The F-111 variants include a terrain-following radar system. The F-111 is powered by two Pratt & Whitney TF30 afterburning turbofan engines. The fuselage is made of honeycomb sandwich and stiffened panels, making it a semi-monocoque structure.
The wing span in full forward and full sweep varies from 16° to 72.5°. The aircraft is capable of attacking in all-weather conditions and delivering ordnance through low-level penetration of enemy defences. It has an internal weapons bay and a cockpit with side-by-side seating in escape crew capsule. The F-111’s design features variable geometry wings and is mostly built with aluminium, titanium steel. The F-111 was given the name Aardvark due to its long and slightly overturned nose. The General Dynamics proposal had similar structural components for both the USAF and US Navy aircraft versions, while Boeing designs lacked this commonality. The General Dynamics designs were selected against the competitors, including Lockheed Martin and Boeing followed, by the TFX contract in December 1962. In 1961 a request for proposals (RFP) was called to develop the aircraft based on the TFX specifically designed for USAF.
"The internal bay could carry Mk 117 type (340kg) bombs and up to Mk 118 (1,400kg) was cleared." Both the USAF and US Navy aircraft versions were similar in design and could carry large warloads at high speeds. They were developed with two-seat and twin-engine features. The aircraft with large long-range designs were based on swing-wing platform. The programme was to develop, consolidate and meet the needs of a supersonic strike aircraft/ tactical fighter-bomber for the USAF and a long range interceptor for the US Navy. The F-111 was developed as part of the Tactical Fighter Experimental (TFX) programme during early 1960s. Tactical Fighter Experimental (TFX) programme In 2007, the Australian Government decided to replace the F-111 aircraft of RAAF with 24 F/A-18F Super Hornets. They will, however, be retired from service in December 2010. RAAF has been the sole operator of the F-111 with 21 aircraft. It was earlier delayed due to problems such as structural integrity and political issues.
The aircraft first entered into the Royal Australian Air Force (RAAF) service in 1973. The Australian F-111 variant was delivered in 1968.