The General Dynamics F-111 Aardvark Build Data

General Dynamics F-111A

The General Dynamics F-111 is one of the most controversial aircraft that ever flew. Perhaps no other aircraft before or since has been so bitterly criticized in the media. It suffered a protracted development cycle in which numerous serious problems had to be identified and repaired, and cost overruns came to be a serious concern. Of the several thousand that had originally been planned, only 562 flightworthy examples of seven different variants were completed. The F-111 was the subject of protracted and bitter debates within the Congress, with opponents denouncing the aircraft as a "flying Edsel" that was more dangerous to the US than it was to any potential enemy.

However, after a prolonged gestation period in which many, many problems had to be identified and fixed, the F-111 turned out to be one of the most effective all-weather interdiction aircraft in the world. Although vilified by some as being an unsafe and dangerous plane, the F-111 series of combat aircraft established the best safety record of any of the aircraft in the Century Series of fighters--only 77 aircraft being lost in a million flying hours. There was no other aircraft in service with the USAF which can carry out the F-111's mission of precise air strikes over such long ranges in all-weather conditions. Although the aircraft has left USAF service, it still serves with distinction with the Royal Australian Air Force and may very well continue until 2020.

The history of the F-111 begins back in the late 1950s. At that time, the Tactical Air Command (TAC) of the USAF expressed a future need for a replacement for the F-100, F-101, and F-105 fighter-bombers which were currently in service. With this goal in mind, on March 27, 1958, the Air Force issued General Operational Requirement (GOR) Number 169, calling for Weapon System 649C, which was a Mach 2+, 60,000 foot altitude, all-weather fighter capable of vertical and short takeoff and landing. The Air Force wanted this aircraft to be ready for operational deployment by 1964.

This GOR lasted only a year, being cancelled on March 29, 1959, because the Air Force recognized that a V/STOL fighter capable of such performance was simply not feasible with the current technology. On February 5, 1960, the Air Force rewrote its requirements and issued System Development Requirement (SDR) No. 17, incorporating most of the provisions of GOR-169 but eliminating the VTOL requirement. It allowed the subsequent development of specific requirements for a new weapon system--WS-324A.

The general requirements of SDR-17 were brought together into Specific Operational Requirement number 183 (SOR-183), issued on June 14, 1960. It called for an attack aircraft capable of achieving a Mach 2.5 performance at high altitude and a low-level dash capability of Mach 1.2. It was to have a short and rough airfield performance, and was to be capable of operating out of airfields as short as 3000 feet in length. The low-level radius was to be 800 miles, including 400 miles right down on the deck at Mach 1.2 speeds. In addition, it was to have an unrefuelled ferry range capable of crossing the Atlantic Ocean. It was to have a 1000-pound internal payload plus a lifting payload between 15,000 and 30,000 pounds.The Air Force considered that a variable sweep wing and a turbofan engine would be needed to satisfy these requirements.

At the same time, the Navy had a requirement for a two-seat carrier-based fleet air defense (FAD) fighter that would replace the McDonnell F-4 Phantom and the Vought F-8 Crusader. This aircraft was to have the ability to loiter on patrol for much longer times with substantially larger and more capable air-to-air missiles, and was to be able to meet and counter threats to the carrier group at much larger ranges.

Originally, the Navy had planned to meet this FAD requirement with the Douglas F6D-1 Missileer. The F6D-1 was a subsonic aircraft that looked a lot like a scaled-up F3D Skyknight. It was to be powered by two 10,000 lb.s.t. Pratt & Whitney TF30-P-2 turbofans, and was to carry a three-man crew (pilot, co-pilot, and weapons system operator). The Missileer was to be capable of remaining on patrol for up to six hours, tracking targets at long range using its powerful Hughes pulsed-Doppler track-while-scan radar and attacking threats with its six long-range Bendix XAAM-10 Eagle air-to-air missiles. The Eagle was a massive long-range air-to-air missile with a maximum speed of Mach 4. It was equipped with an advanced pulse-Doppler active radar homer. The warhead of the Eagle could be either conventional or nuclear.

The F6D aircraft was considered by the Navy to be too costly and too specialized, and was thought to be too slow to be capable of defending itself once its missiles had been launched. Consequently, the F6D and its Eagle missiles were both cancelled in December of 1960 in the last waning days of the Eisenhower administration. This still left the FAD requirement unfulfilled.

The Air Force and Navy requirements were at first sight completely different. However, on February 16, 1961 the new Secretary of Defense, Robert McNamara, directed that the Services study the development of a single aircraft that would satisfy both the requirements of the Air Force's SOR 183 mission and the requirements of the Navy's FAD mission. In addition, McNamara wanted the aircraft to be capable of being used by the Army and the Marine Corps as a close-support aircraft. It was hoped that this strategy would reduce procurement costs substantially. The project came to be known as the Tactical Fighter Experimental, or TFX for short.

It did not take long for the services to convince Secretary McNamara that the close air support mission requirement could not be satisfied by the TFX, and the Marine Corps and the Army were dropped from the program at an early stage. However, Secretary McNamara stuck doggedly to his idea of maximum commonality between USAF and Navy versions of the TFX, and in June 1961, he instructed the Air Force and the Navy to work closely together to combine their requirements before issuing a joint RFP. Although both the USAF and the Navy thought that this idea was completely unrealistic, Secretary McNamara was the boss and they reluctantly followed orders.

Both the USAF and the Navy agreed that the use of variable-geometry wings would be a good idea. However, on just almost everything else, they differed substantially. The Navy favored side-by-side seating for its FAD fighter, whereas the Air Force preferred tandem seating. The Navy wanted an aircraft equipped with a long-range search and intercept radar having a dish 48 inches in diameter, whereas the Air Force needed an aircraft equipped with a terrain-following radar optimized for low-altitude operations. The Navy wanted an aircraft that was optimized for long loiter times at medium to high altitudes at subsonic speeds, whereas the Air Force insisted on an aircraft capable of low-altitude operations and supersonic dash performance. Undaunted, Secretary McNamara pressed forward with the project and directed that the Air Force would be the lead service for the development of a common TFX aircraft.

By August of 1961, the Secretary of the Navy reported to Secretary McNamara that the compromise TFX design could not meet the Navy requirements. The Air Force wanted an aircraft weighing 75,000 pounds gross, while the Navy wanted the gross weight to be kept below 50,000 pounds. In addition, carrier operational requirements necessitated that the overall length be kept below 56 feet so that it could fit aboard existing carrier elevators. McNamara ordered the Navy to accept a design sized to accommodate a 36 inch radar rather than the 48 inch radar it really wanted and to accept a gross takeoff weight of 55,000 pounds.

On September 29, 1961, a new Request For Proposals was issued to Boeing, General Dynamics, Lockheed, Northrop, Grumman, McDonnell, Douglas, North American, and Republic. The Air Force's version of the TFX was to be designated F-111A, with the Navy's version being designated F-111B. In the spirit of commonality, the Air Force and Navy versions did not carry separate designation schemes.

Nine responses were received in early December of 1961. Only Northrop turned down the invitation to submit a proposal. In their first evaluation of the proposals on January 19, 1962, the Air Force Selection Board and a Navy representative endorsed the Boeing proposal, but the Air Force Council rejected the Boeing bid as requiring much more work. In late January of 1962, both the Air Force and Navy agreed that none of the proposals were really acceptable, but that two of them--the Boeing and General Dynamics proposals--warranted further study. A letter contract was issued to each company requesting more design data.

In the spring of 1962, Boeing and General Dynamics submitted second proposals. In May of 1962, both the Air Force and Navy Secretaries rejected the two contractor's second proposals for lack of sufficient data. A third submission took place in late June. At this time, the Air Force endorsed the Boeing proposal, but the Navy was unhappy with their version and refused to commit themselves. A frustrated Secretary McNamara ordered a final competition for later that year on the basis of a point system for categories based on performance, cost, and commonality.

Boeing and General Dynamics resubmitted their final proposals in September of 1962. The Air Force Council, the Air Force Logistics Command, and the Bureau of Naval Weapons (the Navy organization which had replaced the Bureau of Aeronautics in 1959) all indicated that they preferred the Boeing design, but on November 24, 1962 the Defense Department announced that the General Dynamics design had been selected. The reason given for the selection of the General Dynamics proposal was its promised greater degree of commonality and its supposedly more realistic approach to the cost problem.

A political storm broke out, with Senator Henry Jackson leading the fray in Congress in loudly denouncing the choice in no uncertain terms. The Boeing company was located in Jackson's home state of Washington and would lose a lot of business if the decision were allowed to stand. A series of congressional investigations was initiated, and the TFX stayed in the headlines for many months. Nevertheless, the decision of the Secretary stood, and the contract remained with General Dynamics.

The F-111A and B aircraft shared the same primary structure, the same fuel system, the same pair of Pratt & Whitney TF30-P-1 turbofans, and the same two-seat cockpit in which the two crew members sat side-by-side. The side-by-side seating was a concession to Navy demands. The Navy also insisted that the cockpit be capable of doubling as an escape capsule for the crew which could blown free from the aircraft in the case of an emergency and would be able to parachute to the ground as a single unit. The F-111B's nose was 8 feet 6 inches shorter than the F-111A's because of the need of the aircraft to fit on existing carrier elevator decks, and had 3 feet 6 inch extended wingtips in order to increase the wing area so that the on-station endurance time would be improved. The Navy version would carry a Hughes AN/AWG-9 pulse-Doppler radar and an armament of six Hughes Phoenix missiles, which had both evolved from the F6D program. The Air Force version would carry the General Electric AN/APQ-113 attack radar and the Texas Instruments AN/APQ-110 terrain- following radar and would carry an armament of air-to-ground stores.

On December 21, 1962, the Air Force amended the Letter Contract that had initially covered General Dynamics' second competitive proposal and initiated procurement of 18 F-111As (serial numbers 63-9766/9782) and 5 F-111Bs (BuNos 151970/151924). These were to be exclusively research, development, test, and evaluation (RDT&A) aircraft.

Plans originally envisaged using titanium for almost all the airframe in order to save weight, but this proved to be too costly and more conventional materials had to be used.

Since General Dynamics lacked any experience with carrier-based fighters, it teamed with Grumman for the integration of the naval electronics package and Grumman was to assemble and test the entire F-111B aircraft. In addition, Grumman would build the aft fuselage and the landing gear of the F-111A aircraft.

The F-111A mockup was inspected in September of 1963.

By the spring of 1964, AiResearch, AVCO, Bendix, Collins Radio, Dalmo Victor, General Electric, Hamilton Standard, Litton Systems, McDonnell, Texas Instruments and seven other major subcontractors had become involved with the F-111 project. An associate prime contract for the F-111B's Phoenix missiles had been awarded to Hughes. These major subcontractors were doing business with no less than 6703 suppliers located in 44 states. The TFX project became a close approximation to the ideal weapons project--one with at least one contractor located in each Congressional district. :-)

The first test F-111A (serial number 63-9766) rolled out of the General Dynamics Fort Worth, Texas plant on October 15, 1964, 37 months after the OSD go-ahead decision, 22 months after the program's actual beginning, and two weeks ahead of schedule. It was powered by YTF30-P-1 turbofans. Pending the availability of the escape capsule, it was fitted with a pair of conventional ejector seats.

63-9766 took off on its maiden flight from Carswell AFB, Texas on December 21, 1964. Dick Johnson and Val Prahl were at the controls. Although the flight was shortened to 22 minutes because of a flap malfunction, the results were generally satisfactory. On its second flight, on January 6, 1965, the wings were swept from the minimum 16 degrees to the full aft 72.5-degree position. During early flight testing, the F-111A achieved a speed of Mach 1.3. A second F-111A took off on its maiden flight on February 25, 1965.

In 1965, a cost rise from an estimated 4.5 to 6.3 million dollars per aircraft caused the Defense Department to cut the F-111 program sharply. A contract for 431 production aircraft was placed on April 12, 1965. This was more than 50 percent less than the amount originally planned. Eleven production F-111As were added to the extensive test and engineering program.

The ninth aircraft (63-9775) crashed on approach to Edwards AFB on January 19, 1967. The aircraft landed short of the runway due to the wings being accidentally swept in the wrong direction.

The escape capsule was first fitted to F-111A number 11 (63-9777)

The Pratt & Whitney TF30-P-1 turbofan was first flown on an F-111A on July 20, 1965. The first 30 F-111As were equipped with this engine, but they experienced numerous engine compressor stalls, particularly at high speeds and at high angles of attack. These necessitated a change to the 18,500 lb.s.t. TF30-P-3 and to new "Triple Plow I" variable-geometry inlet ducts with larger areas. This engine was later retrofitted in several of the first 30 F-111As. These changes did not entirely cure the stall problems, but the did help somewhat. Many fixes and many years of hard work were necessary before the appropriate air intake geometry was finally found.

Movable underwing pylons were introduced from the fourth production aircraft onward, and from the eleventh production aircraft onward a 20mm M61A1 Vulcan cannon was installed in the internal weapons bay in place of two 750 lb. bombs. However, this cannon was rarely carried by actual operational aircraft, the space in the weapons bay being used for bombs, fuel, or electronics.

In the spring of 1967, a series of tests known as *Combat Bullseye I* were carried out with test F-111As. They confirmed the superior bombing accuracy of the aircraft's radar.

A total of 141 production F-111As were delivered from July 17, 1967. The electronics package was known as the Mk I avionics system. It included a Litton AJQ-20 inertial navigation and attack system, a General Electric AN/APQ-112 attack radar, a Honeywell APN-167 pulsed-type radar, a Texas Instruments AN/APQ-110 terrain-following radar, and Collins ARC-109 UHF and ARC-112 HF radio transceivers.

The underside of the central fuselage of the F-111A was occupied by a giant airbrake which was forced open by a large hydraulic jack. Together with the main landing gear, the presence of this airbrake precluded carrying any bombs or fuel tanks underneath the fuselage. The massive main landing gear had two huge low-pressure tires which, together with the long-stroke legs that are pivoted near the aircraft centerline, enabled no-flare landings to be made at high weights. The large airbrake helped to cover the main gear retraction bay, and wasactually partially extended when the main gear was down. The nose landing gear had twin wheels and was hydraulically steerable.

The Triple Plow I air intakes for the TF30 turbofans were mounted underneath the leading edge of the fixed wing glove. A triangular-shaped wedge was fitted to the upper, inner corner of each intake, and a large planar wedge was mounted ahead of each intake parallel to the sides of the fuselage . The entire intake cowls could be moved forwards or backwards as needed to optimize the air flow into the engines for the given speed or angle of attack. A set of vortex generators is fitted inside the intake ducts to provide a homogeneous flow of air to the engine. The primary disadvantage of the low-mounted air intakes was that they tended to suck up a lot of runway debris, dictating that the F-111A use only prepared runway surfaces that are kept thoroughly swept at all times.

The fixed inner wing has a set of pivoted surfaces that normally lay flush to the surface but at high angles of attack or in high-lift situations they could be extended to improve air flow over the glove-wing junction. >[? The variable-geometry wing outer panels were pivoted to the fixed inner wing gloves and could be driven symmetrically to any sweep angle from 16 degrees to 72.5 degrees. The upper surface of the wing had a set of spoilers which were used for roll control, no ailerons being provided. The main wing had a set of double-slotted flaps which occupied the entire trailing edge of the wing. The flaps were automatically disconnected when the wing was at maximum sweep so that they coule not be operated in such a configuration. A set of slats occupied the entire width of the wing leading edge. These slats could be extended by a rack and pinion system when the aircraft was flying at low speeds or at high angles of attack to increase lift and to prevent the aircraft from stalling.

In an emergency, the cockpit doubled as an escape capsule which separated completely from the aircraft and was blown free from the aircraft by a rocket motor. The pilot and systems officer sat side-by side in a shirt-sleeve environment, eg, wearing no pressure suits or oxygen masks. If they decided to eject, the first step in the sequence was to fire a bunch of explosive guillotines that severed all the hydraulic lines and cables. Then, a quite hefty rocket charge separated the entire cockpit from the plane. When it separated, the ejection capsule took with it a small portion of the fuselage above and to the rear of the cockpit which acted as a stabilizing airfoil. After the chutes opened, anti-radar chaff was dispersed, and a cushion/flotation bag was inflated to cushion the impact when the capsule landed. All of this could be accomplished from zero/zero airspeed/altitude (eg; from an F-111A parked at rest on a runway). In the case of an over-water ejection, the capsule was supposed to be completely submersible and was capable of floating for a considerable amount of time. While the capsule is floating in the water, the joy stick could double as a bilge pump by moving a pin in its base.

The escape capsule was used with success on several occasions. However, there was a problem with excessively hard landings which were so jolting that they injured the crew members. However, I suppose it's better to be injured than to end up as a smoking hole in the ground :-).

The horizontal tailplane was of the all-flying variety with no separate elevator.

At the rear of the tailcone, between the two engine exhausts, was a fuel vent for the dumping of fuel. This device was sometimes used for a rather spectacular airshow demonstration, in which the pilot vents fuel while in afterburner, producing a spectacular torch behind the aircraft.

The F-111A had six underwing pylons for carrying bombs, rockets, or fuel tanks. The outboard underwing pylon on each wing was fixed and could not pivot. Consequently, ordnance could be carried on them only when the wing was set at between 16 and 26 degrees of wing sweep. However the four inboard pylons did pivot and remained parallel to the aircraft centerline throughout the entire sweep range. There was a small internal weapons bay which could accommodate a pair of 750-pound bombs. Alternatively, the bombs in the internal weapons bay could be replaced by a 20-mm M61A1 rotary cannon with 2000 rounds of ammunition.

In an extreme situation, the F-111A could carry as many as 50 750-pound conventional bombs (two of them being carried internally, the rest on the six underwing hardpoints), or 26 1000-pound bombs. However, such loads could only be carried if the wing was swept no more than 26 degrees and would therefore be unlikely to be carried in actual combat. If the wing needed to be swept back at an angle of 54 degrees, the bomb load was limited to 26 750-pound bombs. In standard USAF form, the F-111A's useful payload varies from 8000 pounds to 20,000 pounds, according to range. For example, for a mission range of 1725 miles, the payload is of the order of 16,000 pounds.

The APQ-113 forward-looking attack radar was a large liquid-cooled set that operates in the J-band (16-16.4 GHz). It was used by the navigator sitting in the right hand seat for navigation, air/ground ranging and weapons delivery. It could also be used in the air-to-air mode in conjunction with the 20-mm M61A1 cannon or Sidewinder missiles, although the air-to-air role was not the primary mission of the F-111A.

The F-111A is equipped for midair refueling. A receptacle for a refuelling boom is fitted on the top of the fuselage behind the cockpit. The F-111A has no provision for refuelling by the probe/drogue method.
The first F-111A deliveries took place on July 18, 1967 to the 428th, 492nd and 430th Tactical Fighter Squadrons of the 474th Tactical Fighter Wing based at Cannon AFB in New Mexico. In early 1968, this outfit moved to Nellis AFB.

Based on the results of the Combat Bullseye I tests of the spring of 1967, the Air Force decided to rush a small detachment of F-111As to Southeast Asia under a program known as Combat Lancer. This program was preceded by the Harvest Reaper program of June 1967 which was intended to identify known F-111A shortcomings and to prepare the aircraft for combat. It was anticipated that the Harvest Reaper modifications would enter the F-111A production lines if they were successfully proven in combat.

Six 428th TFS F-111As were allocated to the Combat Lancer program, and departed Nellis AFB for Thailand on March 15, 1968. By the end of that month, 55 night missions had been flown against targets in North Vietnam, but two aircraft had been lost. 66-0022 had been lost on March 28, and 66-0017 on March 30. Replacement aircraft had left Nellis, but the loss of a third F-111A (66-0024) on April 22 halted F-111A combat operations. However, the aircraft remained poised for combat, but they saw little action before their return to the USA in November. It turned out that the three F-111A losses were not due to enemy action but were caused by wing and tail structural defects. One of the Combat Lancer crashes had been traced to a malfunction of the aircraft's tail servo actuator. The USAF later discovered (as a later returning prisoner of war would confirm) that a tailplane problem could cause a sudden and uncontrollable pitch-up and roll. This failure in the flying controls system caused the aircraft to break up in flight. The other two crashes in Vietnam were traced to poor mounting of the M61A1 cannon and to pilot error.

These losses caused a storm of controversy in the USA--Senator William Proxmire denouncing the F-111A as an unsafe and defective plane. The aircraft became known as "McNamara's Flying Edsel", and was accused of being a potential "technological gold mine for the Reds".

However, the Air Force and General Dynamics remained hard at work trying to fix the problems with the F-111A. The 428th TFS of the 474th TFW reached an initial operational capability in the spring of 1968. Harvest Reaper modifications validated by the Combat Lancer operations followed shortly thereafter. The Harvest Reaper modification took a lot longer than expected, and the Wing was not fully operational until July of 1971.

F-111 testing and training incidents (including two crashes in early 1968) had dictated a detailed and involved investigation. On August 27, 1969, a wing-carry-through-box failed during a ground fatigue test. This failure was traced to the manufacturers of the box, the Selb Manufacturing Corp, which had been paying off inspectors for approving unauthorized weldings. Extensive retrofits were required because most F-111As had already cleared the production lines.

The last of 158 F-111As was delivered on August 39, 1969. This total included 17 of the 18 RDT&E F-111As initially ordered in December 1962. The 18th test F-111A was used as a test prototype for the FB-111A bomber program.

The Air Force lost its 15th F-111A on December 22, 1969, the cause being due to failure of the forged wing pivot fitting. All F-111As were grounded the next day. The grounding was lifted on July 31, 1970. This accident cast doubt on the structural integrity of the aircraft and compounded the aircraft's modernization. Each F-111A had to be carefully checked and fixed as necessary.

The F-111A returned to Southeast Asia in September of 1972. They entered combat not long after yet another crash and yet another grounding. Two F-111A squadrons (the 429th and 430th) left Nellis AFB for Thailand. They participated in the Linebacker II aerial offensive against North Vietnam. They flew bombing missions against targets in North Vietnam and Laos in the midst of the monsoon season. They flew without electronic countermeasures escort aircraft or KC-135 tankers. On November 8, 1972, they flew 20 strikes over North Vietnam in weather that grounded other aircraft. Four F-111As could deliver the bomb loads of 20 F-4s.

Shortly after returning to SEA, an F-111A experienced double engine rollback after encountering heavy rain. There were continual problems with the terrain-following radar and the attack radar. Malfunctions of the internal navigation and weapons release system also cropped up on a regular basis. Nevertheless, the 429th and 430th TFS flew some 4000 combat missions with excellent success rates in hitting targets even when visibility was near zero. Only six aircraft were lost in action.

In 1977, surviving F-111As were transferred to the 366th TFW based at Mountain Home, Idaho, where they equipped the 389th and 391st Squadrons.

42 F-111As were converted into EF-111A Raven electronic warfare aircraft.

In 1982, four F-111As were transferred to the Royal Australian Air Force to cover attrition in their F-111C fleet.

Two of the pre-production F-111As (serial numbers 63-9771 and 63-9777) were used for tests by NASA at the Dryden Flight Research Facility between the years 1967 and 1971. Another pre-production F-111A (63-9778) became the Transonic Aircraft Technology demonstrator for NASA. It was fitted with a supercritical wing with a shorter span and blunt wingtips and reduced aspect ratio. It flew for the first time at Edwards AFB on November 1, 1974. During mid-1980, it was flown with laminar flow glove-sections on the wing then rebuilt with a Boeing variable-camber "mission adaptive" wing for Advanced Fighter Technology Integration tests. The F-111/AFTI continued further flight testing until early 1989 when it was retired to the USAF Museum at Wright Patterson AFB in Ohio. However, I don't remember seeing it there when I visited the museum in 1992.

In the early 1990s, surviving F-111As began to be transferred to AMARC at Davis Monthan AFB in Arizona for storage. The last F-111A which had not been converted into EF-111A electronic warfare format reached AMARC in 1997. Some of them are being stored there for possible eventual transfer to Australia to keep their F-111Cs operating for another 20 years. Others have been scrapped.

During its long service, the F-111A/F series never had an official Air Force popular name. However, because of its long, pointed nose, the F-111A came to be known unofficially as the "Aardvark", or just 'Vark for short. In October 1996, at the time of the official retirement of the F-111F from the USAF, the name Aardvark was officially assigned.

Serials of F-111A:
63-9766/9782 General Dynamics F-111A
9776 converted to RF-111A recon aircraft
65-5701/5710 General Dynamics F-111A
66-0011/0058 General Dynamics F-111A
66-9277 General Dynamics F-111A
67-0032/0114 General Dynamics F-111A

Specifications of the F-111A:
Engines: Two Pratt & Whitney TF30-P-3 turbofans, 12,000 lb.s.t. dry and 18,500 lb.s.t. with afterburning. Weights: 46,172 pounds empty, 63,051 pounds combat, 82,819 pounds gross, 98,850 pounds maximum takeoff. Performance: Maximum speed 1453 mph at 53,450 feet, 914 mph at sea level. Initial climb rate 25,550 feet per minute (clean). Service ceiling 58,000 feet, combat ceiling 56,650 feet, absolute ceiling 66,000 feet. Combat radius was 1330 miles, with ferry range being 3165 miles with maximum external fuel being carried. Internal fuel capacity was 5043 US gallons. With underwing fuel tanks, a maximum of 7443 US gallons of fuel could be carried. Dimensions: wingspan 63 feet 0 inches (maximum) and 31 feet 11 1/2 inches (minimum), length 73 feet 5 1/2 inches, height 17 feet 6 inches, wing area 525 square feet. Armament: Armed with one 20-mm M61A1 rotary cannon with 2000 rounds, which was only rarely actually fitted. Up to 30,000 pounds of bombs, missiles, or fuel tanks could be carried on six underwing hardpoints and in the internal weapons bay.

Sources:
1. Grumman Aircraft Since 1929, Rene J. Francillon, Naval Institute Press, 1989.
2. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
3. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
4. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
5. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
6. The World Guide to Combat Planes, William Green, Macdonald, 1966.
7. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
8. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
9. Flying the Frontiers--NACA and NASA Experimental Aircraft, Arthur Pearcy, Naval Institute Press, 1993.
10. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
11. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.

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General Dynamics RF-111A

The RF-111A was to have been a tactical reconnaissance version of the F-111A with additional avionics and camera installations in the weapons bay. It was authorized on December 3, 1965.

One pre-production F-111A (63-9776) was converted as a prototype for the RF-111A and first flew on December 17, 1967. Imagery testing of the converted F-111A took place between December 1967 and October 1968 achieved fairly good results, indicating that the RF-111A might make a good reconnaissance aircraft.

The Defense Department had hoped that the conversion from F-111A to RF-111A configuration could be done in the field in only a few hours, with the reverse conversion being just as simple and straightforward. However, the conversion turned out to be much more cumbersome than expected, taking several days to complete rather than just a few hours. These difficulties caused the Air Force to cancel the whole RF-111A program. The sole prototype is now on display at Mountain Home AFB in Idaho.

Sources:
1. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
2. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
3. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
4. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.

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Grumman EF-111A Raven

In the late 1960s and early 1970s, the Air Force was shopping around for possible replacements for its Douglas EB-66 electronic warfare aircraft. Although the EB-66 still continued to fly combat missions over North Vietnam, it was rapidly beginning to show signs of age.

The Air Force rejected the development of a completely new type of aircraft for this role as being economically impractical because of the small number of aircraft required. At one time, some thought had been given to acquiring the Grumman EA-6B Prowler carrier-based electronic warfare aircraft, but the Air Force was reluctant to acquire yet another aircraft originally developed for the Navy. After some thought, the Air Force concluded in 1972 that the modification of some existing F-111A strike fighters would be the most cost-effective solution.

However, the EA-6B was a four-seat aircraft, and it was concluded that it was impractical to adapt the F-111A to a four-seat configuration because it would reduce internal capacity too much. The only alternative was to develop equipment similar to the Tactical Jamming System of the EA-6B, but capable of being operated by a single electronics warfare officer.

In December 1974, the Grumman Aircraft Corporation of Calverton, Long Island was selected as the prime contractor for this conversion. On January 30, 1975, Grumman was awarded a contract for the modification of two F-111As (serials 66-0041 and 66-0049) as EF-111A prototypes, the E prefix standing for "Electronic".

The modifications included the installation of an AN/ALQ-99E jamming subsystem. Exciters, antennae, and other items were mounted on a pallet inside the internal weapons bay. Other components were mounted inside a 16-foot ventral "canoe"-shaped radome. A fin-tip pod accommodated the electronic countermeasures receivers. The self-protection subsystem consisted of a jamming system and a countermeasures dispensing set. A terminal threat warning subsystem was installed which consisted of infrared and electronic countermeasures receiver sets. The vertical fin had to be reinforced in order to support the fin-tip pod, new electrical wiring had to be installed, 60 kVA generators were replaced by 90 kVA units, and an improved environmental system for electronic equipment cooling was fitted. The cockpit had to be rearranged to accommodate the new electronic warfare officer position, with the flight controls being removed from the right-hand cockpit, the navigation equipment being relocated so that could be used by the pilot in the left-hand seat, and the controls and displays for the electronics warfare officer being installed in the right-hand cockpit.

These modifications resulted in an increase of empty weight from 46,172 pounds for the F-111A to 55,275 pounds for the EF-111A. However, since the EF-111A carried no weapons, its maximum takeoff weight was only 88,848 pounds as compared with 98,850 pounds for the F-111A. The Pratt & Whitney TF30-P-3 turbofans of the F-111A were retained.

Grumman first flew a partially-modified F-111A fitted with a mockup of the ventral canoe in December of 1975. The first EF-111A prototype (serial number 66-0049) flew at Calverton on March 10, 1977. It was complete with fin-tip pod and ventral fairing, but still lacked most of its electronic equipment.
The first flight of a fully-equipped EF-111A (serial number 66-0041) was made on May 17, 1977. This aircraft was delivered to the Air Force to be used by Detachment 3 of the Tactial Air Warfare Center at Mountain Home AFB in Idaho for operational test and evaluation.

Satisfactory results from these tests led to the issuance of a contract for the modification of six more aircraft. Later, 34 more conversions were ordered.

The name *Raven* was officially adopted for the EF-111A.

First deliveries of EF-111A Ravens were made to the 390th Electronic Combat Squadron of the 366th Tactical Fighter Wing at Mountain Home AFB in Idaho in November 1981 and to the 42nd ECS of the 20th TFW at RAF Upper Heyford in February 1984. 42 Ravens had been delivered to the 366th TFW and the 20th TFW by December of 1985. Mountain Home AFB received most of them.

The first operational mission for the Raven took place during Operation Eldorado Canyon, the retaliatory attack on Libya on the night of April 14-15, 1986. During that mission, the 42nd ECS provided three EF-111As plus two spare aircraft to jam the Libyan radar network.

In 1986, General Dynamics was given a contract to install more powerful TF30-P-9 turbofans in the EF-111A.

In May of 1988, a contract for the update of the AN/ALQ-99E by the AIL Division of the Eaton Corporation was cancelled due to cost overruns.

Under an Air Force contract awarded in January 1987, Grumman and TRW Inc. developed the Avionics Modernization Program (AMP) kit for the EF-111A. These kits provided the EF-111A with improved terrain following and navigational radars, a ring laser gyro inertial navigation system, the capability for using the global positioning system, two digital computers, improved cockpit displays, and upgraded communication systems. The first AMP kit was installed in EF-111A 66-0018 in January of 1989. Most existing EF-111As were later to receive this upgrade.

Eighteen EF-111A Ravens were deployed in support of Operation Desert Storm in 1991. They flew over 900 sorties. None were lost in combat, but one was lost in a non-combat related accident and both crew members were killed.

The EF-111A Raven was even credited with a "kill" during Desert Storm. On the night of January 17, 1991, an Iraqi Mirage F.1 flew into the ground while chasing EF-111A serial number 66-0016. Even though the Raven is unarmed and has no air-to-air capability, the Raven crew was given credit for the kill.

The last six EF-111As that had been deployed to Al Kharj Air Base in Saudi Arabia for Operation Southern Watch returned to the USA in April of 1998. This ended the deployment of the EF-111A to the Persian Gulf. The role of the EF-111A will be taken over by Al Kharj-based EA-6Bs flown by mixed Navy and Air Force crews.

In the late 1990s, the EF-111As were all retired from the USAF and sent to AMARC for storage. The USAF retired the final examples of the EF-111A Raven from service with the 429th ECS of the 27th FW at Cannon AFB, New Mexico on May 2, 1998. This marked the end of the line for service of the F-111 with the USAAF, all of the fighter-bomber and strategic bomber versions having been retired several years earlier.

Serials of the EF-111A Raven (all conversions from F-111A blocks):
66-0013/66-0016, 66-0018/66-0021, 66-0023, 66-0027, 66-0028, 66-0030, 66-0031, 66-0033, 66-0035/66-0039, 66-0041, 66-0044, 66-0046/66-0051, 66-0055/66-0057, 67-0032/67-0035, 67-0037/67-0039, 67-0041, 67-0042, 67-0044, 67-0048, 67-0052.

Specifications of the EF-111A Raven:
Engines: Two Pratt & Whitney TF30-P-3 turbofans, 10,750 lb.s.t. dry, 18,500 lb.s.t. with afterburning. Maximum speed: 1377 mph at 40,000 feet. Initial climb rate 11,000 feet per minute. Service ceiling 45,000 feet. Normal range 929 miles. Dimensions: wingspan 63 feet 0 inches (maximum), 31 feet 11 1/2 inches (minimum), length 76 feet 0 inches, height 20 feet 0 inches, wing area 525 square feet. Weights: 55,275 pounds empty, 70,000 pounds loaded, 88,948 pounds maximum takeoff.

Sources:
1. Grumman Aircraft Since 1929, Rene J. Francillon, Naval Institute Press, 1989.
2. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
3. The Fury of Desert Storm--The Air Campaign, Bret Kinzey, McGraw- Hill, 1991.
4. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
5. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
6. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
7. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
8. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
9. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
10. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.

___________________________________________________________________________

General Dynamics/Grumman F-111B

The F-111B was the naval version of the TFX fighter project, which had been decreed by Secretary of Defense McNamara to be designed in common with the Air Force version, even though the requirements were completely different. In retrospect, this turned out to be a serious mistake.

The Navy F-111B was intended as a fleet defense fighter, whereas the F-111A was intended as a long-range air-to-ground strike aircraft. The F-111A and B aircraft shared the same primary structure, the same fuel system, the same pair of Pratt & Whitney TF30-P-1 turbofans, and the same two-seat cockpit in which the two crew members sat side-by-side. In an emergency, the cockpit doubled as an escape capsule which was blown free from the aircraft to parachute to the ground. However, the F-111B's nose was 8 feet 6 inches shorter than the F-111A's because of the need of the aircraft to fit on existing carrier elevator decks, and had 3 feet 6 inch extended wingtips in order to increase the wing area so that the on-station endurance time would be improved. The Navy F-111B version would carry a Hughes AN/AWG-9 pulse-Doppler radar and an armament of six Hughes Phoenix missiles. The Air Force F-111A version would be provided with the General Electric AN/APQ-113 attack radar and the Texas Instruments AN/APQ-110 terrain-following radar and would carry an armament of air-to-ground stores.

Both the Phoenix missiles and the AN/AWG-9 radar had evolved from the earlier abortive Douglas F6D Missileer program. The Phoenix missile fire-control system owed much to the USAF's ASG-18 system which had originally been developed for the abortive F-108 Rapier project.

Since General Dynamics lacked any experience with carrier-based fighters, it teamed with Grumman (an experienced builder of naval fighters) for the development and subsequent manufacture of the F-111B. It was decided that Grumman would do the integration of the naval electronics package and would assemble and test the entire F-111B aircraft. In addition, Grumman was selected as a subcontractor to build the aft fuselage and landing gear of both Navy and Air Force F-111 aircraft.

The first F-111B (Bu No 151970) was assembled at Bethpage from components produced by both General Dynamics and Grumman. It was powered by the same pair of Pratt & Whitney TF30-P-1 turbofans that powered the F-111A. Pending the availability of the escape capsule, the first F-111B was equipped with a pair of conventional ejector seats. It was rolled out at Bethpage on May 11, 1965 and transported by land to Calverton. It made its first flight at Calverton on May 18, flown by Ralph "Dixie" Donnell and Ernie von der Heyden. Aside from a problem with compressor stall (as already experienced by the F-111A), the first flight was trouble-free.

The first Naval Preliminary Evaluation was held at NATC Patuxent River in October of 1965. The F-111B was already in trouble since it was seriously overweight. Takeoff weight for a fully-equipped aircraft was estimated at nearly 78,000 pounds, well over the upper limit of 55,000 pounds as required by the Navy.

The problems with the overweight F-111B were so severe that General Dynamics and Grumman were forced into a Super Weight Improvement Program (SWIP), most of the changes being incorporated into the fourth and subsequent F-111Bs. The fourth F-111B (BuNo 151973) was fitted with an escape capsule in place of the individual ejector seats that were fitted to the first three F-111Bs. However, the fitting of this capsule more than offset the weight reductions achieved by the SWIP, and the F-111B remained grossly underpowered. Range was also below specifications and could only be increased by adding more fuel, making the aircraft even heavier.

In order to correct the underpower problem and to eliminate compressor stalls (which were also problems for the land-based F-111As), the first of 32 production F-111Bs (BuNos. 152714/152717, 153623/153642, and 156971/156978) which had been ordered was powered by a pair of TF30-P-12 turbofans, each rated at 12,290 lb.s.t. dry and 20,250 lb.s.t. with afterburning.

The third F-111B (BuNo 151972) was allocated to trials with the Phoenix missile system. Four Phoenix missiles were to be carried on swiveling pylons underneath the wings, with two Phoenix missiles being housed inside the fuselage weapons bay. The first successful firing of a Phoenix missile took place in July of 1967.

By October 1967, the Navy was finally convinced that the F-111B was a lost cause and would never be developed into a useful carrier aircraft and recommended that the project be terminated. The axe finally fell in May of 1968 when both houses of Congress refused to fund F-111B production. On July 19, 1968, a stop-work order was issued and the terms of formal contract termination were agreed upon in December of that year. This included the cancellation of 28 production F-111Bs (BuNos 153623/153642 and 156971/156978). The seventh and last F-111B (152715) was delivered on February 28, 1969, after $377 million had spent on the program.

Tests continued at Point Mugu and China Lake even after the F-111B program had been terminated. BuNo 151974 was used for carrier trials aboard the USS *Coral Sea* (CVA-43) in July of 1968. The Hughes Aircraft Corporation flew BuNo 1542715 (the last F-111B completed before project termination) until the spring of 1971. By that time, a total of 1748 hours had been flown and two F-111Bs had been lost in crashes. 151973 crashed during takeoff at Grumman's Calverton, Long Island facility on April 21, 1967, and 151971 was lost off the coast of California on September 11, 1968. The surviving five aircraft were permanently grounded in 1971. I am uncertain if any F-111Bs still survive today.

Serials of the F-111B:
151970/151974 Grumman/General Dynamics F-111B
152714/152717 Grumman/General Dynamics F-111B
152716 and 152717 were not completed.
153623/153642 Grumman/General Dynamics F-111B - contract cancelled
156971/156978 Grumman/General Dynamics F-111B - contract cancelled

Specifications of the F-111B:
Engines: Two Pratt & Whitney TF30-P-1 turbofans, 12,000 lb.s.t. dry and 18,500 lb.s.t. with afterburning. Later, two TF30-P-12 turbofans, rated at 12,290 lb.s.t. dry and 20,250 lb.s.t. with afterburning were fitted. Performance: Maximum speed 1450 mph at 40,000 feet, 780 mph at sea level. Initial climb rate: 21,300 feet per minute. Service ceiling 44,900 feet. Normal range 1092 miles. Maximum range 3178 miles. Weights: 46,500 pounds empty, 72,421 pounds loaded, 86,563 pounds maximum takeoff. Dimensions: wingspan 70 feet 0 inches (maximum) and 33 feet 11 inches (minimum), length 68 feet 10 inches, height 16 feet 8 inches, wing area 550 square feet. Armament: Armed with six Hughes AIM-54A Phoenix air-to-air missiles, four underneath the wings and two inside the fuselage weapons bay. In addition, a 20-mm M61A1 cannon could be fitted.

Sources:
1. Grumman Aircraft Since 1929, Rene J. Francillon, Naval Institute Press, 1989.
2. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
3. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
4. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
5. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
6. The World Guide to Combat Planes, William Green, Macdonald, 1966.
7. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
8. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
9. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
10. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.
11. E-mail from Douglas Reynolds on crash of 151973.

___________________________________________________________________________

General Dynamics F-111C

On October 24, 1963, the government of Australia agreed to purchase 24 F-111As as a replacement for the English Electric Canberra.

Initially, the Australian F-111 was to be virtually identical to the USAF F-111A, but by April of 1966 the configuration had changed to that of a hybrid between the F-111A and the FB-111A, to be designated F-111C. The F-111C was equipped with eight underwing pylons mounted on an F-111B-type larger span wing (span of 70 feet when fully extended). It was equipped with with an FB-111 type of reinforced undercarriage. The twenty-four F-111Cs were given the USAF serial numbers 67-125/148. Their RAAF serials were A8-125/148.

The first F-111C was officially handed over on September 6, 1968. However, the problems with the F-111A's wing carry-through box slipped delivery of the remaining 23 F-111Cs to late 1969. To make matters worse, the whole F-111 fleet had to be grounded pending verification of their overall structural integrity. The remaining F-111Cs awaiting delivery to Australia were stored at Fort Worth until the structural integrity of the F-111 could be confirmed.

In April of 1970, a joint agreement between General Dynamics and Australia deferred the RAAF's acceptance of the F-111C pending the verification of their structural integrity. The RAAF was to lease F-4E Phantoms as an interim aircraft while new wing carry-through boxes were installed on all F-111Cs before being delivered to the RAAF. This refurbishment program began on April 1, 1972.

In 1973 the F-111C was finally ready for delivery to the RAAF. The first F-111C was formally accepted on March 15, 1973. Australian crews came to the USA, and, one-by-one, these crews flew their new mounts from Fort Worth to McClellan AFB. Once at McClellan, the Australian crews flew several training missions before leaving for Australia. The first F-111C reached Australia on June 1, 1973, followed shortly thereafter by the rest of the fleet. The last F-111C was delivered to Australia on December 4, 1973.

The F-111Cs were operated by Nos. 1 and 6 Squadrons based at Amberley, Queensland. The F-111Cs replaced the RAAF's fleet of English Electric Canberra bombers that has been in use since the 1950s.

The F-111C carries the APQ-113 forward-looking attack radar, which is used for navigation, for air-to-ground ranging and for weapons delivery. In theory, this radar can also be used in the air-to-air mode in conjunction with the internal 20-mm cannon or Sidewinder missiles carried underwing, although this is not the primary mission of the F-111C.

A8-133 was lost in 1977 when it struck three pelicans. This demonstrated the vulnerability of the aircraft to birdstrikes during low-altitude high-speed operations, and laminated ADBRIT windshields were fitted to the entire fleet.

The RAAF had originally also ordered six reconnaissance versions known as the RF-111C. However, the USAF cancelled the entire RF-111A/RF-111D program in 1968, leaving the RAAF without the reconnaissance version it had ordered. In order to meet this need, a contract was signed with General Dynamics on December 31, 1974 for four of the original F-111Cs to be converted to the RF-111C reconnaissance role and delivered to Australia. The first of these (A8-126) was flown on April 17, 1979 and was redelivered in August of 1979. The remaining three aircraft were converted at Amberley using General Dynamics-supplied kits during 1980. The reconnaissance suite is mounted on a pack that fits inside the weapons bay. The reconnaissance "kit" comprises two CAI KS-87C split vertical framing cameras, a Fairchild KA-56E low-altitude and KA-93A4 high altitude panoramic camera, and a Honeywell AN/AAD-5 Infrared Linescanner. There is a TV viewfinder which assists with line up for the photo run. The aircraft is also equipped to allow photography of the AN/APQ-113 attack radar display. The RF-111C retains full conventional attack capability. The four RF-111Cs bear the serials A8-126, -134, -143, and -146, and they serve with No. 6 Squadron.

The F-111C can also carry the AN/AVQ-16 Pave Tack laser designation pod, fitted inside the weapons bay. A rotating cradle allows the pod to be carried entirely internally, rotating down only when actually in use. The first Pave Tack-capable F-111C (A8-138) was modified at Fort Worth in December 1983, ith the rest of the surviving fleet being modified at Amberley beginning in 1985.

The F-111C can carry the AGM-084A Harpoon anti-ship missile. The AGM-88 HARM anti-radiation missile was also tested on the F-111C, but has not been procured.

In 1982, four F-111As surplus to USAF requirements were transferred to the RAAF as attrition replacements. Before being delivered, they were modified to F-111C standards with longer span wings and strengthened undercarriages. Their RAAF serial numbers were A8-109, -112, -113, and -114.

Under Project AIR 5225, the RAAF planned to carry out an Avionics Upgrade Program (AUP) of the F-111C's largely analog avionics suite to fully digital standards. In August of 1990, Rockwell was given a contract to update 18 F-111Cs and four RF-111Cs at its Palmdale plant. Fully 90 percent of the electronics in the F-111C were replaced by more capable units. The upgraded aircraft has an improved digital Stores Management System which provides compatibility with a wider ranging group of weapons. The avionics is based on the MIL_STD-1553B digital databus. There is a new digital computer complex with two IBM AP-102 mission computers. The computer has a pre-programmable data cartridge which allows a fully-planned mission to be loaded into the aircraft before flight. There is a new navigation system built up around the Honeywell 423 (AN/ASN-41) ring laser gyro, augmented by a Rockwell-Collins GPS. The analog flight control system is replaced by a digital fly-by-wire system. The terrain-following radar is replaced by a Texas Instruments AN/APQ-171 system, and the beam mapping attack radar is upgraded to AN/APQ-169 standards. The first upgraded F-111C was A8-132. The last AUP-modified F-111C was returned to the RAAF at Amberley in November 1999. This upgrade should keep the RAAF F-111Cs flying until the year 2020.

In October 1992 it was announced that Australia planned to buy 18 surplus F-111Gs from the USAF to augment the 22 surviving F-111Cs in the RAAF fleet. The price was described as "bargain basement", about $AUD60-80M; plus $AUD10-15M per plane for upgrades. ($AUD 1 =~ $USD 0.72). Delivery began in 1994. One aircraft (68-272) was taken from AMARC storage, but the remainder were taken directly from Cannon AFB when the 27th Fighter Wing exchanged them for F-111Es.

There were some differences between the F-111Gs and the existing F-111Cs. The F-111G had a longer range and better ECM capabilities than the original F-111C. The F-111Gs had the more powerful TF30-P-107 turbofan rather than the P-103 of the F-111C and had different (Triple Plow II) intakes. The F-111G was not compatible with the Pave Tack laser designation pod and had an AYK-18 mission computer. Before their retirement, the F-111Gs were fitted with the ASN-41 ring laser gyro inertial navigation system and were fitted with an APN-218 Doppler. After delivery to Australia, these planes were fitted with the same digital flight control system as was fitted to the F-111Cs under AUP.

There was some thought given to having the F-111Gs also go through the AUP upgrade
Initially, it was planned to use the F-111Gs primarily as spares, but also perhaps as a possible attrition reserve. However, by the time that the first two F-111Gs had arrived at Amberley on September 28, 1992, it had been decided that some of them would be used as an "in-use" reserve, and No 6 Squadron was given a flight of 6 F-111Gs.

Since 1994, the F-111Cs and RF-111Cs have been re-engined with TF30-P-109RA 20,840 lb.s.t. turbofans taken from retired F-111Ds and EF-111As.

There are plans to fit the F-111Cs with indigenous ALR-2002 radar warning receivers replacing the existing ALR-62. There are also plans to fit a radar jammer to replace the Sanders ALQ-91 and ALQ-137 defensive electronic countermeasures package. The ALR-2002 began flight trials during late 1999. AN/ALE-40 chaff/flare dispensers are replacing the AN/ALE-20. A request has been issued for a podded electronic countermeasures jammer, the AN/ALQ-131 and AN/ALQ-184 being possible contenders.

In 1998, the RAAF announced that it planned to keep its F-111 fleet flying until at least 2020. In order to support this plan, it was decided that the remaining F-111Gs would be reactivated and that ten redundant ex-USAF airframes would be acquired for cannibalization to form an attrition reserve. The RAAF will have the option to purchace the attrition reserve airframes directly at a later time should the need arise.

Serials of Australian F-111Cs
A8-125/A8-148 USAAF serials 67-125/148
A8-106 ex USAF F-111A 67-106 held in reserve in USA for RAAF spares
A8-109 Ex USAF F-111A 67-109 purchased by RAAF in 1982 and upgraded to F-111C
A8-112 Ex USAF F-111A 67-112 purchased by RAAF in 1982 and upgraded to F-111C
A8-113 Ex USAF F-111A 67-113 purchased by RAAF in 1982 and upgraded to F-111C
A8-114 Ex USAF F-111A 67-114 purchased by RAAF in 1982 and upgraded to F-111C

A8-259 Ex USAF F-111G 68-259
A8-264 Ex USAF F-111G 68-264
A8-265 Ex USAF F-111G 68-265
A8-270 EX USAF F-111G 68-270
A8-271 ex USAF F-111G 68-271
A8-272 ex USAF F-111G 68-272
A8-274 ex USAF F-111G 68-274
A8-277 ex USAF F-111G 68-277
A8-278 ex USAF F-111G 68-278
A8-281 ex USAF F-111G 68-281
A8-282 ex USAF F-111G 68-282
A8-291 ex USAF F-111G 68-291

Sources:
1. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
2. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
3. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
4. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
5. The World Guide to Combat Planes, William Green, Macdonald, 1966.
6. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
7. Flying the Frontiers--NACA and NASA Experimental Aircraft, Arthur Pearcy, Naval Institute Press, 1993.
8. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
9. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.
10. Aussie Aardvark: The General Dynamics F-111, Jon Lake, Air International, Vol. 56, No. 4, April 2000.

___________________________________________________________________________

General Dynamics F-111D

F-111D was the designation given to a more advanced version of the F-111. It was powered by a pair of Pratt & Whitney TF30-P-9 engines, each rated at 12,000 lb.s.t. dry and 18,500 lb.s.t. with afterburner. The aircraft were equipped with Mark II microprocessor avionics with improved air-to-air capability. This system was a first generation version of what later came to be known as a "glass" cockpit.

In addition, the F-111D was provided with Triple Plow 2 air intakes, which were intended to correct the F-111's seemingly chronic problems with compressor stall. The Triple Plow 2 intakes were mounted four inches farther from the airframe in order to improve the boundary layer "plow", and the translating cowl was replaced by a series of blow-in doors. These blow-in doors were a set of auxiliary inlets which enabled extra airflow to reach the inlet duct during takeoff or when the engine is at full power but the aircraft is moving slowly. They are normally sealed closed by spring-loaded doors which are pushed open by air pressure when additional air flow is needed.

The Mark II avionics system included 7 major components--an inertial navigation set and attack radar built by the Autonetics Division of North American Rockwell, an IBM computer system, converter and panels by the Kearfott Division of Singer-General Precision, Inc., an AN/AVA-9 integrated display set by the Norden Division of United Aircraft Corporation, a Doppler radar by the Canadian Marconi Company, a horizontal situation display by the Astronautics Corporation of America, and a stores management set by the Fairchild Hiller Corporation. The main forward-looking attack radar of the F-111D was the APQ-130, with MTI, Doppler beam sharpening, and illumination for radar-guided AAMs.

The F-111D was ordered on May 10, 1967. The first F-111D (68-0085) flew on May 15, 1970. It was equipped with the new P-9 engines but did not have a complete Mark II system. It was delivered to the Air Force on June 30, 1970, only one day after the lifting of the F-111 delivery hold order imposed after the F-111A crash of December 11, 1969.

The F-111D went through a rather protracted development cycle before it was deemed fit for service. There were difficulties in integrating the various complex electronic components with each other. The Autonetics attack radar needed several improvements in its initial design, and the Norden integrated display set required extensive changes. The radar problems required that the radar doppler unit be redesigned, which in turn caused interface problems with the Norden integrated display set. By late 1969, the Mark II system was still not ready. By mid-1970, the problemms with the Norden integrated display set were still not resolved. Several months of acrimonious arguments between Autonetics and Norden followed, Norden claiming that the IDS's original specification was beyond the state of the art.

Development problems with the F-111D's advanced avionics caused so many delays that the Air Force decided to acquire the simpler F-111E as an interim version.

It was not until November 1, 1971 that the first F-111D was delivered to the 27th TFW at Cannon AFB in New Mexico, the third TAC Wing to receive the F-111. This aircraft was the sixth F-111D produced (68-0090). It was equipped with a full Mark II avionics system, featuring one of Norden's early IDS productions. The initial operational capability with the 27th TFW was in September 1972. Eventually, the F-111D equipped the 522nd, 523rd, and 524th Squadrons of the 27th TFW.

Throughout the rest of 1972, TAC's few F-111Ds continued to be crippled by avionics problems. The horizontal situation display was prone to frequent failures, delivery of field ground equipment was late, and depot support was poor. There were excessive reliability and maintenance problems with the Mk II avionics, so severe that at times line mechanics were forced to resort to buying parts at Radio Shack. Operational readiness remained low all throughout 1973, and the abort rate of the F-111D was higher than that of other F-111s. It was not until January of 1974 that the F-111D was finally declared operationally ready.

96 F-111Ds were delivered between June 30, 1970 and February 20, 1973. The serials were 68-0085/0180. Beginning in 1991, surviving F-111Ds were retired to AMARC. The last F-111D went to AMARC in December of 1992. Substantial number of these machines remain there in storage.
The RF-111D was a proposed but unbuilt reconnaissance version of the F-111D with very sophisticated avionics. The program was abandoned in September of 1969 because of lack of funds. Cheaper RF-111As were to be acquired, which were in turn cancelled as well.

Sources:
1. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
2. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
3. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
4. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
5. The World Guide to Combat Planes, William Green, Macdonald, 1966.
6. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
7. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
8. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
9. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.
10. E-mail from Mike Walters on maintenance problems with Mk II electronics.

___________________________________________________________________________

General Dynamics F-111E

Because of late delivery and protracted development of the F-111D, 94 F-111Es were ordered with simplified avionics and the TF30-P-3 turbofan engine, but with the Triple Plow 2 air intakes of the F-111D. They were ordered in 1968. Even though the F-111E had a later series letter than the F-111D, the E preceded the D into service.

As compared to earlier F-111 variable-geometry air intake configurations, the Triple Plow 2 air intakes were four inches farther from the airframe in order to improve boundary layer "plow", and the translating cowl was replaced by a series of three blow-in doors. These blow-in doors are a set of auxiliary inlets placed on the sides of the main intakes which enable extra airflow to reach the engine inlet ducts during takeoff or when the engines are at full power but the aircraft is moving slowly. They are normally sealed closed by spring-loaded doors which are pushed open by air pressure when additional airflow to the engines is needed.

The F-111E carried the APQ-113 forward-looking attack radar which is used by the navigator for navigation, air-to-ground ranging and weapons delivery. It can also be used in the air-to-air mode, although this is not the primary mission of the F-111E.

The first flight of an F-111E took place on August 20, 1969, and deliveries to the Air Force took place from 1969 to May 28, 1971. A total of 94 were built, and serials were 67-115/124 and 68-001/084.
TAC's 27th Tactical Fighter Wing at Cannon AFB reached initial operational capability with the F-111E in the fall of 1969. The wing had 29 F-111Es by December, but these flew under restrictions until the Air Force was convinced that the wing longerons were safe.

The F-111E program slipped another six months following the December 1969 loss of the 15th F-111A. The Air Force grounded the entire fleet and refused to accept the delivery of any more F-111s until the problems were fixed. All F-111Es went through the Recovery Program and other structural inspections that stemmed from the December 1969 accident. The order that grounded the fleet was finally lifted in July of 1970.

The F-111E had integral radar homing and warning equipment and possessed electronic countermeasures capability. This made the aircraft needed in Europe right away. Despite the program's slippage, the first two of the 70 F-111Es slated for the 20th Tactical Fighter Wing in Europe were sent to the RAF Upper Heyford base in Oxfordshire, England on September 11, 1970. The wing became fully operational with the type in November of 1971. These F-111Es remained based at Upper Heyford up to 1993, when defense cutbacks and the overall decline in the threat from the East resulted in their withdrawal to stateside bases.

F-111Es of the 20th TFW were used in Operation *Desert Storm* in early 1991, flying out of bases at Incirlik, Turkey. They lacked the precision guided munitions capability of the later F-111F, and so they carried mainly Mk 82 or Mk 84 standard conventional bombs and other conventional ordnance against targets in the northern part of Iraq. None were lost in combat, which is a remarkable testament to the efficacy of the F-111E in combat.

The first prototype of the F-111E series (67-0115) was loaned to NASA for tests in support of the Integrated Propulsion Control System. This was a "fly-by-wire" system installed in the weapons bay which automatically controlled the variable-geometry inlet and the turbofans. The first IPCS flight was carried out on September 4, 1975. The last flight was on February 27, 1976. After the tests were completed, the F-111E was returned to the Air Force and restored to its original configuration. It later served as a chase plane for the Rockwell B-1 strategic bomber.

Surviving F-111Es were all transferred to AMARC in 1993/94. A few are on display in museums.

Sources:
1. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
2. The Fury of Desert Storm--The Air Campaign, Bret Kinzey, McGraw- Hill, 1991.
3. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
4. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
5. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
6. The World Guide to Combat Planes, William Green, Macdonald, 1966.
7. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
8. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
9. Flying the Frontiers--NACA and NASA Experimental Aircraft, Arthur Pearcy, Naval Institute Press, 1993.
10. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
11. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.

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General Dynamics F-111F

The F-111F was the final F-111 version produced for the Tactical Air Command (TAC). It was ordered on July 1, 1970. It differed from the F-111D in having more advanced electronics which were nevertheless simplified and more reliable. It carried the Mark IIB avionics suite which combined F-111D and FB-111A navigational and digital computer systems (but excluding the F-111D's AN/APN-189 Doppler radar navigation set) plus numerous other FB-111A components such as the AN/APQ-144 attack radar and some simpler, less costly avionics systems used by earlier F-111s. The APQ-144 attack radar of the F-111F has a new 2.5-mile display ring made possible by a 0.2 s pulse-width capability. The F-111F also featured an improved landing gear. It was powered by a pair of 25,100 lb.s.t. TF30-P-100 turbofans (although the first 30 had TF30-P-9s and were subsequently re-engined).

On October 13, 1971, a modified F-111A started the F-111F Category I flight test program. A problem with overheating of the aft centerbody fuselage was corrected by an engineering change. The first F-111F entered service with the 374th TFW based at Mountain Home AFB in Idaho in January 1972. The entire wing became operationally ready in October of 1972. There were some initial problems with the TF30-P-100 engine--difficulties were encountered with afterburner stalls in cold weather, with tail-feather seal leakage, and with inlet guide vane cracking.

The last F-111F was delivered to the USAF in September of 1976. 106 F-111Fs were built. Their serials were 70-2362/2419, 71-0883/0894, 72-1441/1452, 73-0707/0718, and 74-0177/0188. Another twenty-four were cancelled (serials were 71-0895/0906 and 75-0210/0221).

After serving with the 366th TFW, the F-111Fs were reassigned to the 48th TFW based at RAF Lakenheath in the United Kingdom. F-111Fs also serve with the 57th Fighter Weapons Wing based at McClellan AFB in California.

The F-111F had an internal weapons bay, but in most aircraft this bay was normally occupied by extra fuel or by other equipment. Many F-111Fs carry the Ford AVQ-26 Pave Tack pod semi-recessed in the weapons bay. The Pave Tack was equipped with a laser designator and forward-looking infrared (FLIR) which were used for the delivery of laser-guided bombs with pinpoint accuracy. The laser and FLIR were boresighted inside a powered turret giving magnified clear pictures of targets that were integrated with the cockpit avionics displays and weapons-aiming systems. Although all of the F-111 marks could drop laser-guided bombs, only the F version had the laser suite to designate targets.

24 F-111Fs from the 48th TFW based at Lakenheath spearheaded the US attack on Libya on the night of April 14, 1986, striking targets in Tripoli with laser-guided and retarded bombs. The lead ship during the Libya strike was 70-2390. One F-111F (serial number 70-2389) was lost to ground fire during the attack.

During *Desert Storm*, the 67 F-111Fs of the 48th TFW operated from air bases in Saudi Arabia. Because of their ability to deliver precision-guided ordinance in all-weather conditions, they played a key role in the destruction of the Iraqi command and control structure and in the elimination of key targets in the Kuwait theatre of operations. These aircraft flew 2500 sorties, destroyed 2203 targets, including direct hits on 920 tanks, 252 artillery pieces, 245 hardened aircraft shelters, 13 runways, 113 bunkers, and 12 bridges. A total of 5500 bombs were dropped. Almost 85 percent of these bombs were precision guided munitions. When Iraqi forces deliberately opened a oil pumping station manifold to allow oil to leak into the Persian Gulf, an F-111F was selected to deliver a GBU-15 electro-optically guided bomb against the manifolds to stop the flow.

On the last night of the war, two F-111Fs delivered the hastily-devised GBU-28 deep-penetrator bombs against Iraqi command and control bunkers. These bombs could penetrate over 100 feet of earth or 22 feet of concrete.

No F-111Fs were lost in combat during the Persian Gulf War, which was a remarkable testament to its combat effectiveness.

In 1995/96, the F-111Fs were all retired to AMARC and placed in storage. This ended the service of the F-111 series with the USAAF, with the exception of the EF-111A Raven electronic warfare aircraft, which soldiered on for a couple more years. Most of them still sit there today. During its long service, the F-111A/F series never had an official Air Force popular name. However, because of its long, pointed nose, the F-111A came to be known unofficially as the "Aardvark", or just 'Vark for short. In October 1996, at the time of the official retirement of the F-111F from the USAF, the name Aardvark was officially assigned.

Specification of F-111F:
Engines: Two Pratt & Whitney TF30-P-100 turbofans, 25,100 lb.s.t. with afterburning. Performance: Maximum speed: 1453 mph at 53,450 feet, 914 mph as sea level. Initial climb rate 25,550 feet per minute (clean). Service ceiling 56,650 feet. Combat radius 1330 miles. Maximum ferry range 3634 miles with external fuel. Dimensions: wingspan 63 feet 0 inches (maximum), 32 feet 0 inches (minimum), length 73 feet 6 inches, height 17 feet 0 inches, wing area 525 square feet. Weights: 46,172 pounds empty, 82,819 pounds gross, 98,950 pounds maximum takeoff. Internal fuel capacity was 5043 US gallons, with a total capacity of 7443 US gallons when maximum external fuel is carried.

Sources:
1. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
2. The Fury of Desert Storm--The Air Campaign, Bret Kinzey, McGraw- Hill, 1991.
3. General Dynamics Aircraft and their Predecessors, John Wegg, Naval Institute Press, 1990.
4. Post-World War II Fighters: 1945-1973, Marcelle Size Knaac, Office of Air Force History, 1986.
5. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
6. The World Guide to Combat Planes, William Green, Macdonald, 1966.
7. Modern Air Combat, Bill Gunston and Mike Spick, Crescent Books, 1983.
8. The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston, Orion, 1988.
9. F-111 Aardvark--USAF's Ultimate Strike Aircraft, Tony Thornborough, Osprey Aerospace, 1993.
10. F-111 Aardvark, Hans Halberstadt, Specialty Press, 1992.

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General Dynamics FB-111A

The FB-111A was the all-weather strategic bombing version of the F-111, intended as an interim successor to the B-52 and B-58 of the Strategic Air Command. It was initially developed as Weapon System 129A.

The FB-111A differed from the F-111A primarily in having a longer fuselage (75 feet 7 inches as compared to 73 feet 5 1/2 inches) to accommodate the additional fuel required for its strategic mission. In order to provide a longer range and greater load-lifting capability, the FB-111A had the extended wing of the F-111B (unfolded span of 70 feet as compared to 63 feet). It also had a stronger undercarriage and landing gear, and was powered by TF30-P-7 turbofan engines. It featured the Mark IIB avionic subsystem planned for the F-111E, which comprised an improved F-111A attack radar, an inertial navigation system, digital computers, plus some advanced displays of the later Mark II that equipped the delayed F-111D.

The FB-111A was actually the first F-111 version to fly with the new Triple Plow II air intakes, beginning with the third example (67-0161). The Triple Plow II intakes were mounted four inches farther from the airframe in order to improve the boundary layer "plow", and the translating cowl was replaced by a series of blow-in doors which fed additional air to the engines during takeoff or when the aircraft was moving slowly.

The development of the FB-111A was prompted by the slow progress of the Advanced Manned Strategic Aircraft (AMSA) program and by fears that fatigue failures in the B-52 fleet might come earlier than expected. A proposal to resume production of the Convair B-58 Hustler was rejected as being too costly. In the spring of 1963, the Air Force turned to General Dynamics for a solution to its problem. In November of 1963, General Dynamics responded with a suggestion for two strategic versions of the F-111A. In order to hasten availability, the Air Force decided on June 2, 1965 that the least modified version was the one that they would go with. The designation FB-111A was applied, which is sort of curious since the design was basically a modified F-111A, which would have suggested that the designation should have been BF-111A.

The Air Force initially planned to order 263 FB-111As (210 to equip 14 squadrons, plus 20 for combat crew training and the remaining 33 for support and testing). It wanted them in service quickly, the first FB-111As being expected to be operational as early as fiscal year 1969.

Secretary of Defense Robert McNamara publically announced plans to develop the FB-111A on December 10, 1965. However, the implementation of the program was postponed until February 1966, when the FB-111A had been added to the basic F-111A RDT&E contract and Congress had approved the funds. In January of 1966, Secretary McNamara asked the Air Force to begin contract definition on Mark II avionics systems for both the FB-111A and the delayed F-111D, with maximum commonality being a key requirement. The primary weapon of the FB-111A was to be the Boeing-designed AGM-69A Short-Range Attack Missile (SRAM).

A modified RDT&E F-111A (serial number 63-9783) was converted as the prototype of the FB-111A and flew for the first time on July 30, 1967. It achieved Mach 2 on its first test flight.

Pending the availability of the P-7 engine, it was decided that the first few FB-111As would receive P-12A engines (the USAF version of the Navy P-12 engine that was used in the F-111B) and these engines would subsequently be brought up to the P-7 configuration once the aircraft was in service.
The first production FB-111A aircraft flew on July 13, 1968. It was accepted by the Air Force on August 30, 1968. A second FB-111A was delivered on October 25. These two planes were powered by TF30-P-12A engines. Problems with the Mark IIB avionics slowed further deliveries, with the Air Force not accepting its next FB-111A until June 23, 1969. This aircraft featured a fully-developed Triple Plow II air diverter, a complete Mark IIB avionics system, and the new P-7 engines.

The first 6 FB-111A production aircraft were used for testing. Category III tests did not finish until July 31, 1972.

A total of 263 planes was projected when the FB-111A program began. This was reduced to 126 on November 28, 1968 because of rising costs and production delays with the basic F-111 program. The final cut took place on March 16, 1969, with the total FB-111A order being reduced to 76.

On October 8, 1969, the 7th FB-111A entered service with the 4007th Combat Crew Training Squadron of the 340th Bomb Group at Carswell AFB. Even though the FB-111A was officially declared operational, it had yet to reach the combat forces. After reaching operational capability, the 4007th CCTS relocated to Plattsburg and became part of the 380th Strategic Aerospace Wing.

The primary offensive armament of the FB-111A was the Boeing-designed AGM-69A SRAM, a missile designed primarily to neutralize enemy defense systems such as radars, SAMs, and other anti-aircraft systems. The launch weight of the SRAM was 2230 pounds, and it was powered by a two-pulse solid-fuel rocket motor. Maximum speed was Mach 2.8-3.2, and the range varied from 35 to 105 miles, depending on the mission. The guidance system consists of a Singer Kearfott inertial guidance operating in conjunction with a Delco on-board computer. Various attack trajectories could be chosen, ranging from semi-ballistic to terrain-following. During an actual operational mission, the bombardier would selects each missile in turn, update the inertial guidance system, then would let the missile drop. The rocket motor would then fire and accelerate the missile to Mach 3. fast enough to fly and steer with body lift and three tail fins. When the missile neared the target, the second propulsion stage would then ignite for the final run in to the target. The SRAM carried a W6 nuclear warhead with an explosive yield of 200 kilotons.

FB-111A testing of the SRAM began on March 27, 1970. Initial test started poorly--in almost a year, there were only seven successes out of 11 launches. However, by early 1961, the results began to get better, with the final score being 15 successes out 19 launches during the entire test series.

In January 1971, the FB-111A achieved initial operational capability with the 509th Bomb Wing (393 and 715 Squadrons) based at Pease AFB in New Hampshire. After many difficulties, the 509th was finally declared fully combat-ready in October of 1971. The 380th Strategic Aerospace Wing (528 and 529 Squadrons, plus the 4007th Combat Crew Training Squadron) at Plattsburg AFB in New York became combat ready in 1972. These were the only two SAC wings to receive the FB-111A.

The last production FB-111A (68-0291) was delivered to SAC on June 30, 1971.

The FB-111A could carry two AGM-69A SRAMs in the internal weapons bay along with two more on the inner underwing pylons. Typically, four 600-US gallon drop tanks were carried on the outermost underwing pylons, although the SRAMS carried underneath the innermost underwing pylons could be replaced by another pair of 600-gallon drop tanks, bringing the total number of drop tanks to six. The non-swiveling outer pylons are intended for subsonic flight only and are jettisoned when wing sweep exceeds 26 degrees. Alternatively, up to 24 750-pound conventional bombs could be carried externally. The FB-111A could also carry six gravity nuclear weapons or a B77 nuclear bomb. A total offensive load of 35,500 pounds could be carried.

The FB-111A carries the APQ-144 forward-looking attack radar, which was derived from the APQ-113 of the F-111A. It adds a beacon mode, a photo recording capability, and a north-oriented display.
Landing gear malfunctions persisted throughout mid-1971 and were finally solved by a simple field modification. In late 1971, weapons delivery was still marginal, reflecting failures in the inertial navigation system. There were some problems with engine flameouts following use of the afterburner, these being probably caused by moisture in the engine sensing line.

In April 1972, new SRAM-carrying equipment was installed on the FB-111A.

In November 1970, the FB-111A took top honors in bombing and navigation during SAC's competition at McCoy AFB in Florida. The first overseas deployment of the FB-111A was the entrance of two Pease FB-111As in a Royal Air Force bombing and navigation meet at RAF Marham.

As the Rockwell B-1B Lancer came into service, the FB-111A became redundant to SAC needs, and most surviving FB-111As were converted into ground attack configuration and assigned to training units operating out of Cannon AFB in New Mexico. During 1988, the designation F-111G was adopted for the FB-111As that were to be converted eventually to serve in the tactical role when displaced from SAC.

In June of 1990, the SRAM missiles were removed from the inventory because of safety concerns regarding the integrity of their W69 nuclear warheads in the event of a fire. After that, the FB-111As stood alert with only g