The F-111 remained in service with the Australian Air Force until 2010, where it was affectionately known as the ‘Pig.’ Starting with a batch of 24 F-111Cs received in 1973, the Australians acquired an additional 15 FB-111s and four F-111As. Though never used in combat, the F-111s gave Australia the ability to project military force across the vast distances of the Pacific Ocean, enhancing its diplomatic clout.
The General Dynamics F-111 Aardvark was a low-altitude strike plane born out of a shotgun wedding between competing Air Force and Navy requirements—with Defense Secretary McNamara as the minister. Despite its troubled adolescence, it grew into a capable high-tech night bomber that lasted decades in service, noted for its sleekly elegant profile.
In the early 1960s, the Air Force came to realize that new, radar-guided surface-to-air missiles such as the Soviet SA-2 could reach its slow, high-altitude bombers. In response, it devised a new concept: a smaller long-range supersonic bomber that could skim close to the ground, below radar systems. At the same time, the U.S. Navy was looking for a fast, long-range carrier-based interceptor armed with air-to-air missiles that could take out Soviet bombers from a distance.
Newly appointed Defense Secretary Robert McNamara was convinced that a single aircraft could satisfy both requirements, thereby saving on development costs. The Army and Navy were less keen on compromising their visions, but were forced to cooperate on the so-called TFX program. A contract was awarded to General Dynamics in 1962. Because the design was smaller than Air Force strategic bombers, and the service eschewed the “attack” designation used by the Navy, it was designated with an “F” for fighter.
The F-111 was built around two powerful yet fuel-efficient TF30 turbofan engines with new afterburner technology. A capacious fuselage could accommodate bomb loads of up to 31,000 pounds and fuel for missions up 2,500 miles long, with external tanks adding another 1,000 miles. The large plane weighed twenty tons empty—or more than twice that loaded.
The designers of the F-111 faced a challenge: they needed a plane that could fly at very high speeds, but still take off or land on a short runway. Using smaller wings would create less drag, allowing the aircraft to fly faster—but also create less lift, requiring the aircraft achieve higher speeds before it take off, in turn necessitating a longer runway. For example, the other supersonic fighter-bomber of the era, the F-105 Thunderchief, had very small wings—and required airstrips over a mile long for takeoff, limiting which airfields it could operate from.
The F-111’s designers adopted the new technology of variable-geometry, or “swing” wings. These permitted the wings to swing out during takeoff to generate maximum lift, and then would tuck inward midflight to achieve higher speeds. The F-111 was the first of several major designs that used the technology.
The two-man crew sat side by side in a cockpit pod. If they needed to escape, a rocket boosted the pod upward, which then floated to the ground on a parachute, just like a space capsule.
A key innovation was the F-111’s revolutionary new terrain-following radar, which mapped the ground directly in front of the plane and then automatically adjusted the flight path to avoid collision. This allowed F-111s to fly as low as two hundred feet above the surface and make precise adjustments at high speed without crashing—even when flying at night, or in bad weather conditions. The F-111’s talent for hunting in darkness, nose close to the ground, was what earned it the appellation “Aardvark.”
Early F-111s did show promise, capable of flying over the speed of sound at Mach 1.2 at low-altitude, or more than double that (Mach 2.5) at high altitude—all the while requiring only a 2,000 foot runway to land. It was the first tactical aircraft to cross from the United States to Europe without mid-air refueling.
However, the F-111’s design was biased in favor of the Air Force’s specifications. The carrier-based interceptor version, the F-111B, performed abominably in trials, struggling to exceed Mach 1. The expensive forced compromise that was the naval version was finally scrapped, leaving everyone millions of dollars poorer. Many of the more promising design elements of the F-111B made it over to the F-14 Tomcat, however.
Deployment in Asia
The Air Force F-111s didn’t have an auspicious debut in combat. After a detachment of six F-111As was deployed to Vietnam in 1968, three of them crashed in just fifty-five missions, all of them accidents linked to defective wing stabilizers. The Air Force was forced to withdraw the F-111 and correct the flaw at a cost of $100 million.