Few aircraft flying today have created as much controversy as the General Dynamics F-111 Aardvark. The product of a developmental project that attempted to provide an advanced common solution for both the US Navy and Air Force, the F-111 was grounded for several months even before its maiden flight which took place on the 21st of Dec 1964. Following its introduction into US service, it’s one and only export customer, the Royal Australian Air Force (RAAF), had to wait an entire 10 years before delivery of this advanced swing-wing fighter/bomber could commence. As such, the numerous technical problems encountered and continuously increasing costs resulted in an extremely difficult gestation for the new multi-mission fighter/bomber. On the positive side however, this incredible aircraft represented technical accomplishments that resulted in the F-111 becoming one of the most effective fighter/bombers of our times. This is highlighted by the fact that the RAAF will continue to operate its small fleet of F-111’s until 2010. Although many believe that the real reason why the RAAF is replacing it’s ‘Pigs’ (the unofficial Australian name for the F-111 – Afrikaans for Earth Pig) next year has more to do with political expedience than a true necessity to replace this highly capable and potent weapons platform. 

DEVELOPMENT & HISTORY

The original specification of the then Tactical Fighter Experimental (TFX), which was later to be renamed the F-111, was based on a US Air Force requirement dating back to the 14th of June 1964, which foresaw an aircraft incorporating variable geometry wings and the ability to deliver a nuclear weapon utilizing supersonic speed at very low level out to a range of at least 500 miles. utilizing internal fuel only. Another important part of the Specific Operational Requirement (SOR) 183 was the ability to take off and land from unpaved airfields (the latter was a mixed blessing). The solid landing gear as well as the huge low pressure tires allowed the F-111 to take of and land from unprepared runways, nevertheless there was an ever-present danger that Foreign Object and Debris (FOD) could be ingested into the air intakes due to the low design of the landing gear.

At the same time the latest development by the US Navy, the Douglas F-6D Missileer, was cancelled by the newly elected Kennedy administration because it was seen as a backward step, particularly when compared to aircraft it should be replacing such as the McDonnell Douglas F-4 Phantom II . To save costs, the former Secretary of Defense, Robert McNamarra favoured a joint development program for both the US Navy and Air Force. However, because of the many operational discrepancies between the two services and the very different operational concepts and mission requirements there was not one agreement between the two services. As such, the new jack of all trades was starting to become the master of none.

Altogether there were four different design competitions, all of which were won by the Boeing Corporation of Everett Washington. However, even with Boeing being declared the winner Robert McNamara selected Grumman and General Dynamics to compete for the lucrative contract to design the nation’s newest military aircraft, with the selection process eventually leading to a political dispute. Grumman was responsible for the Navy version, the so called F-111B, which made its maiden flight on the 18th of May 1965. Despite the fact that the F-111B was progressing well in the tests for a carrier born aircraft, it remained too heavy and too expensive which resulted in the program being cancelled in 1968. From this moment on the US Navy could now pursue its own ideas, and when US congress gave green light for the development of the new carrier fighter known as VFX, what transpired was the remarkable Grumman F-14 Tomcat. The TFX program was not in vain as many of the features from the former Missileer and F-111B programs were combined to strongly influence the development of the F-14, these features included the AWG-9/AIM-54 Phoenix weapon system, variable geometry wings and the TF-30 Turbofan engines.

In many aspects the F-111 was a quantum leap forward. For example, it was the very first operational fighter bomber which employed variable geometry wings while its powerful afterburning turbofan engines provided power, good range and low fuel consumption. Terrain Following Radar (TFR) was a key feature utilized for the first time and its high tech multi-mode radar system allowed the crew to track up to 24 targets simultaneously. One highly controversial feature of the F-111 was the crew`s escape module which possessed several advantages in comparison to conventional ejection seats. One example demonstrating the effectiveness of this concept was the ejection of an F-111D crew who lost control of their aircraft at Mach 2. Remarkable, both officers were back on flying duty the very next day, something which would have been absolutely impossible if they would have ejected utilizing the standard Martin-Baker ejection seat.

One particular disadvantage of the F-111 however was its complex weapon system and subsequently very high price, obviously one of the prime reasons why the F-111 was not a huge export success. Apart from service within the US Air Force, the Royal Australian Air Force (RAAF) was the only export customer for this highly sophisticated combat aircraft. The British government cancelled its order for the procurement of 46 F -111K fighter/bombers and four TF-111K trainer aircraft due to high costs (or at least that was the officially released statement). Initially the British Aardvarks were designated to replace the indigenous BAC TSR.2, which was also cancelled by short-sighted British politicians.

The Australian Governments decided to purchase the F-111 in October 1963 and of the original 24 aircraft ordered, four have been modified to become R/F-111C Reconnaissance platforms. Because of this, an additional four ex-USAF F-111A’s were purchased from the US government as replacements. These A models were upgraded to C standard and in 1985 the entire fleet were subject to a MLU (Mid-Life Upgrade) which included the installation of the Pave-Tack targeting system and the ability to carry sophisticated weapon systems, such as the AGM-84 Harpoon Anti-Ship Missile (ASM), AGM-88 High Speed Anti-Radiation (HARM) missile and the indigenous Karinga Cluster Bomb Unit (CBU) system. Following their retirement from US service a further 15 F-111G (ex FB-111A) were purchased by the Australian Government (14 for operational service and one aircraft to operate as a weapon test aircraft for Aircraft Research & Development Unit (ARDU), based at RAAF Edinburgh in South Australia. At the beginning of the 1990’s the entire RAAF F-111 fleet received a comprehensive avionics upgrade under the Avionic Update Program (AUP) which provided the F-111 with a state of the art avionics/navigation package.

By the mid 1990’s most US F-111’s were already out of service. Only a USAF Electronic Intelligence (ELLINT) gathering variant, the EF-111 RAVEN (sometimes also referred to and the Sparkvark), was still operational for a few further more years. The RAVEN replaced the venerable Douglas EB-66 within the USAF Electronic Warfare role. For this task, the F-111A was equipped with the powerful AN/ALQ-99E Jamming Radar, numerous Electronic Counter Measures (ECM) systems and a more capable electrical power plant rated at 90 kVA (the original generator was rated at only 60 kVA). Because of these comprehensive electronic modifications (for example installation of the ALQ-137 Jammer, ALR-62 radar warning receiver and ALR 23 radar countermeasure receiver) the take of weight of the EF-111 had increased to over 23 tons, five tones over the mean take-off weight of the standard Aardvark and it was because of this weight why EF-111 was never equipped with an offensive weapon system. The EF-111A prototype made its maiden flight on the 17th of May 1977 and in total some 42 EF-111A’s were converted from existing aircraft. The EF-111 RAVEN was the very last variant of the F-111 series to see operational service and was decommissioned in 1998 due to cost cutting measurments of the former US Government. Most of the RAVEN’s were put in mothballs at the Aerospace Maintenance and Regeneration Centre (AMARC) located at Davis-Monthan AFB, Arizona.

One weak point of the F-111 was its Pratt & Whitney TF30-P-3 engines that were often subject to compressor stalls. The manufactorer attempted to solve this problem by modifiying the air inlet ducts, which was only partly successful. Although the Aardvark was designed as an all-weather combat aircraft, the engines could occasionally stall due to water ingestion, particularly in heavy rain. Another problem, at least in the first couple of years of its service career, was that the technologically over-stressed radar system was problematic and at times failed to operate. Another problem was with the aforementioned landing gear. As sturdy and reliable as it was in order to absorb hard carrier landings, its low design also meant that Foreign Object and Debris (FOD) could easily be sucked into the air intakes. This is why the F-111 could only operate from very clean, paved runways. And last but certainly not least was the structural weak points within the box section of the wings joints, the cause of which led to a fatal crash of one aircraft on the 22nd December 1969.

Despite all of these problems the F-111 still had quite a successful career. The first missions were flown in 1967 over Vietnam, which was definitely far too early following development. This was highlighted by several aircraft being lost due to technical problems or pilot error and not due to enemy action. After identifying and rectifying the majority of the aforementioned problems several deployments in South-East Asia were extremly successful. In no less than 4,000 missions only 6 aircraft were lost, a loss ratio which was far below that of other combat aircraft. On April, the 14th 1986 24 F-111F operating from RAF Lakenheath (belonging to the 48th Tactical fighter wing) flew a precision raid against the Libyan capitol city of Tripoli. These aircraft were equipped with the brand new Ford AVQ-26 Pave-Tack electro-optical targeting system which was the very first time this system/platform combination was used in anger. More successful missions were flown in the first Gulfwar in 1991. Flying more than 2,500 missions (official statement of the US DoD) some 2,203 targets were destroyed, including 920 tanks, 245 aircraft shelters, 12 bridges as and 113 bunkers. Not a single F-111 was lost in action – a truly remarkable record.

Testimony to the longevity of the F-111 and professionalism of the crews that fly and maintain them is held every two years at Nellis AFB Nevada. Red Flag provides the opportunity for air forces from around the world to exercise within a disilar air combat environment involving a diverse range of combat mission scenarios. Since 1980 the RAAF has been represented at Red Flag by F-111 aircraft and crews of 82 Wing RAAF. In all missions the RAAF have acquitted them self well as a reliable and effective capability and to the amazement of the other participating air forces, and in particular the Americans, RAAF F-111’s have maintained a 100 per cent sortie success rate at the end of the exercise, not bad at all for a 40 year old platform.A very special feature of an F-111 display is the popular ‘dump and burn’, where fuel is released and then lit with the afterburners. This spectacular sight was a common sight on the Australian air show scene and provides a spectacular, although safe demonstration of speed and power. Interestingly, within the US the torching was strictly prohibited following an incident where a USAF Aardvark almost became a barbequed pig!

Sadly, the decommissioning of the F-111 in Australian service means the life of this extraordinary aircraft will soon come to an end. With its initial teething problems solved the F-111 later went on to become an extremely formidable platform that was at the forefront of Americas and Australia’s strike capability for many years. While it never was a perfect plane, it did however fulfill its niche role of strike/interdiction perfectly. As its excellent service demonstrates the RAAF exploited these capabilities which eventually led to the vindication of the General Dynamics F-111 Aardvark as a formidable weapon system. The F-111 was truly an aviation masterpiece, and will be dearly missed by all, not to mention many aviation enthusiasts world wide!

Robert Kysela / CHK6

Release 1.0/2010

languages

Imprint
Team CHK 6
Editorial

Release 1.0/2010

languages

Imprint
Team CHK 6
Editorial