50 F-111B | STORY: STEWART WILSON

The one that got away

The General Dynamics F-111 overcame masses of ‘bad press’ in its early days and many technical difficulties to be recognised as arguably the best strike bomber of its era. But there was one version which failed due to the flawed philosophy behind its development: the F-111B carrier-based fleet defence fighter for the US Navy. GENERAL DYNAMICS F-111B 51

Above: The first F-111B (Bu151970) fleet defence fighter first flew on 18 May 1965 but three years later the programme was cancelled after just seven had been built. The main external difference to the land- based F-111 models is the shortened nose. US Navy

THE F-111 QUALIFIES as a remarkable aircraft on all counts. It incorporated a high level of new and advanced technology, overcame its problems and went on to perform superbly as a strike and later electronics warfare platform. In retrospect it can be seen that the US Navy’s F-111B was never going to work. It was a victim of its political architect’s vision for an aircraft that could be both a large land-based strike bomber and a naval fighter. That architect was US Secretary of Defense Robert Strange McNamara, whose ‘procedural commonality’ philosophy was intended to create industrial, technical and financial efficiencies. It had the opposite effect. was given prime responsibility for the F-111B programme due to General Dynamics’ lack of experience with naval aircraft. Grumman, on the other Rollout of the first F-111B from Grumman’s hand, had a long and illustrious history in that field. >>> Long Island, New York facility. Note the Gulfstream I and C-2A Greyhound in the background. Grumman 52 GENERAL DYNAMICS F-111B

Above: The first F-111B in flight in 1965 with its underfuselage airbrake extended. As on all F-111s, this also served as the door for the main undercarriage. US Navy Below: US Secretary of Defense Robert McNamara (centre), author of the ‘procedural commonality’ concept which resulted in the F-111. He is photographed here in Vietnam with General William Westmoreland.

To quote another writer: “This was the perceived role by the press, most politicians version which would have proven McNamara's and of course the public. ‘commonality’ concept.... had it worked.” It To them a fighter was an aircraft which didn't, and the F-111B never served with its shot down other aircraft, something which intended customer. This was neither General despite its ability to carry air-to-air missiles for Dynamics’ nor Grumman’s fault, rather the self-defence, the F-111 never was. flawed philosophy under which it was Its ultimate success resulted from not only developed. sorting out the technical problems, but also recognising that McNamara’s ‘Jack Of All SHAKY START Trades’ philosophy was impossible to achieve First flown in , the F-111 and accepting that the F-111 was – despite its suffered serious issues during its development designation prefix – a strike bomber. and early service career: an advanced powerplant that wasn't properly matched to PROCEDURAL COMMONALITY its inlets; excessive weight; excessive drag; first production aircraft to use turbofan engines In 1960, the USAF and US Navy issued massive cost increases; and structural with afterburners, the Pratt & Whitney TF30. separate requirements for a new Tactical problems in the variable-geometry wings' Considering how effective the mature F-111 Fighter Experimental (TFX) and Fleet Air carry-through box, the structural heart of the turned out to be in the strike role, it's worth Defence Fighter (FADF), respectively. That all wings and the point from which they pivot. recounting the aircraft's intended roles as seen changed in with the arrival of The variable sweep wings (or `swing wings' by those who wrote its original requirements. the John F Kennedy presidency and a new as the media dubbed them) were only one of It was to be a tactical bomber, strategic bomber, Secretary of Defense, Robert McNamara. the several ‘firsts’ incorporated within the tactical fighter, reconnaissance platform and a McNamara was a man on a mission. F-111. Although the wing geometry was the naval heavy fleet defence fighter all in one. As a former Vice President of the Ford Motor area which generated the most interest in the It proved to be impossible to reconcile all Company, he was a successful businessman popular press and the F-111 was the first these requirements satisfactorily despite the and economist who, as a senior executive of aircraft with variable sweep to enter service, F-111's advanced design features. The carrier- a large corporation, was an advocate and a couple of its operational characteristics borne fleet defence fighter version – the F-111B practitioner of efficiency in business. His indicated its true importance. – was the main bugbear and was abandoned attitude to the business of defence spending In its land-based production form, the after seven prototypes had been flown. differed little from the financial management F-111 was the first aircraft able of making An unfortunate part of the whole exercise he employed at Ford. Where possible, wasteful blind, first pass attacks on precision targets was the designation of the aircraft as a duplication had to be got rid of. and the first capable of penetrating hostile air ‘fighter’, the result of the programme being The term ‘procedural commonality’ was space at extremely low altitudes in automatic called the Tactical Fighter Experimental used to describe what McNamara was trying terrain following (TF) mode with the Terrain (TFX) in its early days, the omission of the to achieve, and among his first targets were Following Radar (TFR) telling the autopilot key word ‘strike’ from this abbreviation the TFX and FADF projects which were where to point the aeroplane. It was also the causing a misconception of the F-111's combined into one as the TFX. GENERAL DYNAMICS F-111B 53

F-111 DESIGN COMMONALITY

AIR FORCE COMMON • Basic Stucture • Propulsion System • Primary Flight Controls Crew Station Tyres • Secondary Power 85% COMMONALITY • Refrigeration Package • Crew Escape Capsule • Reconnaissance • Penetration Aids Nose Gear Fire Power Fixed Wing Control System Pylon

Radome & Electronics Bay

Wing Extension

AMCS

Tyres MLG Radome Arrester Hooks Nose Gear • M & TC Crew Station • Fuel System A General Dynamics diagram illustrating the areas of commonality and difference between the Air Force and Navy versions of the F-111. The ‘procedural commonality’ theory was intended to SIMILAR produce significant development, acquisition and operating cost savings. NAVY

In February 1961 it was announced that the requirements of the US Air Force taking for the naval version), , Lockheed, one aircraft type with the maximum possible precedence over those of the US Navy. From McDonnell, North American and Republic. commonality between the various sub-types that point the Navy's version was effectively Initial evaluations revealed that none of the would be developed to meet the requirements doomed. submissions met the difficult requirements of both. Six companies responded to the Requests (sustained Mach 1.2 at low altitude was a Combining multiple roles within the same for Proposal at the end of 1961: General huge problem in itself) but that the Boeing basic design would save resources, time and Dynamics () and Grumman teamed and GD/Grumman designs were the best, in money, so the theory went. Despite warnings together (with the latter primarily responsible that order. >>> from just about everyone that such a project was simply not possible, McNamara pushed ahead. The Air Force/Navy antagonism began immediately the TFX programme began to be defined during the course of 1961. Not unnaturally, each service wanted its own specific requirements to be given priority and there were many clashes as to what form the aircraft should take. Fundamental things like how the two man crew should be seated. The USAF wanted a tandem arrangement because of lower drag and better visibility, while the Navy, although it preferred tandem seating for the same reasons, had to settle for a side-by-side design to ensure this large aeroplane's fuselage was not too long to be compatible with the aircraft carriers which would be its base. Progress was slow, causing McNamara to The first and second F-111Bs (Bu151970/71) intervene in October 1961 and announce that together over Long Island in 1965 with wings the TFX would be a fighter/strike type with swept fully forward and fully aft. US Navy 54 GENERAL DYNAMICS F-111B

Another competition in April 1962 once The hearing took testimony from the landing field requirements) and high titanium again resulted in all the designs falling short companies involved, the USAF and Navy and content would also have probably caused of the mark but with the Boeing and GD several other interested government agencies. delays. submissions getting closer to it. As before, the Its conclusion supported McNamara’s decision The clincher – at least in McNamara’s eyes Boeing design was adjudged the most suitable. and also found that no improprieties had been and in view of his ‘procedural commonality’ In June 1962 the third and final competition committed, accusations of which had been philosophies – was the fact that the Boeing was opened. Both the Boeing and General freely bandied about. design had only 50 per cent commonality Dynamics designs were now acceptable in terms McNamara presented his case in favour of between the Air Force and Navy versions of performance and general specification with the General Dynamics/Grumman proposal whereas GD’s had 80 per cent. the Boeing project yet again on the top of the and won his adversaries over, citing better On 21 December 1962 General Dynamics list. Like the Boeing submission and several of fatigue life, higher maximum speed, lower and Grumman signed the TFX/F-111 contract the other earlier contenders, General Dynamics’ radar signature and superior electronic with the US Government, covering an initial design featured variable geometry wings. countermeasures capability. 23 development aircraft – 18 F-111As for the McNamara conceded that the Boeing USAF and five F-111Bs for the Navy. The CONTROVERSY proposal appeared to have superior ferry world's most sophisticated strike aircraft was That Boeing would win the TFX contract range, loiter capability and low speed formally underway but the controversies and seemed to be a foregone conclusion. The handling – at least on paper – but he was able problems had only just begun. trouble was, nobody told that to Robert to convince the hearing that Boeing's costings McNamara, who, on 24 November 1962 were unrealistically optimistic. That turned PROBLEMS, PROBLEMS announced the General Dynamics/Grumman the tide in favour of his original selection. As the programme developed and even before proposal to be the winner of the Hindsight tends to confirm McNamara's the first F-111A had flown on 21 December competition... and all hell broke loose! opinion. Boeing's proposed powerplant, the 1964, the aircraft was beset with problems Representatives of the two states most General Electric MF-295 turbofan, existed concerning rapidly increasing weight and price. effected by the decision (Texas for General only as a set of specifications at the time and The original USAF estimates called for a Dynamics and Washington for Boeing) argued would not have been ready to fly before 1967, maximum takeoff weight of no more than the relative merits of the two aircraft, the press while General Dynamics' Pratt & Whitney 45,000lb (20,412kg), an admittedly totally got involved, there was a public and TF30 was at an advanced stage of design. unrealistic figure. By preliminary mockup government outcry and a Congressional In addition, Boeing's top-mounted engine stage this had increased to 70,000lb Hearing was called when legal action was intakes, its use of thrust reversers (something (31,752kg) and by the time of the prototype’s threatened. the GD design did not need to make the first flight to 92,000lb (41,731lb). Production F-111As finally settled on a MTOW of 91,300lb (41,413kg). While this degree of weight growth was not an insurmountable or crippling problem for the USAF versions of the F-111, it proved to be fatal for the Navy's F-111B, which finally weighed in at 79,212lb (35,930kg) gross, a massive 26 per cent above guarantees and nearly half as much again as the original estimates. Costs, too, seemed to have no limit to their upward spiral, a factor which played a great part in the public debate which later surrounded Australia’s purchase of the aircraft. Unit cost increased by 50 per cent to $US6.05 million by the time the first aircraft were delivered to the USAF in 1967, a very substantial amount nearly five decades ago. While all this and the problems which emerged once the F-111 was flying and in service make the aircraft sound like a complete lemon, the facts are that despite

Three shots showing the fifth F-111B (Bu151974) operating from the USS Coral Sea during trials in July 1968, the only time the aircraft went to sea. By then, the F-111B programme had already been axed. US Navy GENERAL DYNAMICS F-111B 55

At the end of the day, the F-111B proved to be too heavy for its intended role despite attempts to reduce it. Costs also escalated alarmingly, these and the technical problems the F-111 was generally suffering at the time combining to result in the cancellation of the ‘B’ and the end of Robert McNamara’s ‘procedural commonality’ dream. US Navy everything, General Dynamics’ revolutionary six targets simultaneously at maximum range ers, the TF30 is a high compression, two-spool design was – and remained – the most and in any weather conditions. Flight testing turbofan, the world’s first with thrust augmenta- effective strike aircraft of its type in the world. began in 1965 from a Douglas DA-3B tion (afterburner) which was fully modulated, It was simply a matter of realising that Skywarrior and in March 1969 during testing allowing any setting between maximum dry and Robert McNamara's ‘procedural commonality’ an F-111B successfully engaged a pair of maximum augmented thrust. concept was impossible to achieve, instead drones. This was eight months after the F-111B Pratt & Whitney began development of concentrating on successfully fixing the F-111's programme had been axed. the new turbofan as a private venture in 1958 problems and recognising its considerable Phoenix deliveries began in 1973 for the under the company designation JTF10A, later virtues as a low level under the radar strike Tomcat. Between then and 1980 when the TF30. Early development was in aircraft utilising advanced avionics and production ended, Hughes delivered 2,566 of conjunction with France’s Snecma, which used aerodynamics. them, each one costing more than a million US derivatives of the engine to power its experi- dollars. mental Mirage IIIV vertical takeoff and landing F-111B FOR THE NAVY (VTOL) aircraft and Mirage G variable sweep Externally, the F-111B differed from its land- PRATT & WHITNEY POWER two-seater in 1965 and 1967, respectively. based brethren by virtue of its shorter, upward The F-111A’s Pratt & Whitney TF30-P-3 The French connection did not progress folding nose radome, this to reduce the space turbofan giving 18,500lb (82.3kW) of thrust beyond that, but in 1961 the JTF10A/TF30 required to house the aircraft on US Navy with afterburner was installed in the five F-111B was selected to power the General Dynamics carriers. It also featured strengthened development aircraft. The more powerful TFX/F-111 entry. undercarriage, the equipment specific for 20,250lb (90.0kN) thrust with afterburner There were some development problems carrier operations and the longer-span wings TF30-P-12 was planned for production models associated with the design of the TF30’s which would also appear on Strategic Air and fitted to F-111Bs numbers six and seven, advanced compressor and the inlets also Command’s nuclear-capable FB-111As and the pre-production test aircraft. caused problems for the F-111 programme Australia’s F-111Cs. Intended from the start for supersonic fight- generally. The engine itself broke new >>> Initial orders covered five development F-111Bs and 24 production aircraft against a planned total procurement of 705. GENERAL DYNAMICS F-111B For its primary role as a fleet air superiority fighter, the F-111B featured the highly advanced Hughes AN/AWG-9 Pulse-Doppler fire control radar housed in the shortened nose in combination with up to six equally advanced Hughes AIM-54 Phoenix radar guided air-to-air missiles, two in the internal weapons bay and four under the wings. Hughes began development of the Phoenix in 1960, the missile becoming the most sophisticated (and expensive) AAM in the world and only able to fired from the F-14 Tomcat once the F-111B had been cancelled. A single missile was capable of covering an area of over 31,000 square kilometres thanks to its range of 200 kilometres, speed of more than Mach 5 and advanced fire control system. As intended for the F-111B, the six missiles planned to be carried could engage and attack 56 GENERAL DYNAMICS F-111B

What the US Navy wanted all along. The Grumman F-14 Tomcat first flew in December 1970 and deliveries started in June 1972. The F-111B’s variable sweep wings, Phoenix missiles, fire control radar and TF30 engines were retained. US Navy

ground, not just because it was the first tion the two problems produced a potentially axed in July when a ‘cease further work’ order turbofan to feature a fully variable afterburner dangerous mix. was issued. but also because it was the first supersonic The first hint of this occurred on the Despite the cancellation, testing continued application for an afterburning turbofan, and prototype F-111's second flight in January for the moment including carrier trails then one which had to operate at both 1965 when pilot Dick Johnson attempted conducted by the fifth aircraft (Bu151974) extremely low and high altitudes. supersonic flight with the wings swept fully aboard the USS Coral Sea in July 1968. These Because of these conflicting requirements, back. Severe compressor stall in full were successful, but it was too late. Testing of the aerodynamics around the inlet area were afterburner resulted. Four years of redesign the Phoenix missile using the sixth F-111B very complex and the upshot was an and development of the F-111’s inlet system continued into 1969. engine/inlet incompatibility which made the resulted, during which time many Despite attempts to reduce its empty F-111 susceptible to compressor stall thanks configurations were tested. weight, the F-111B was still nearly 4.5 tonnes to airflow distortion across the engine The final design as applied to the or 25 per cent heavier than guarantees and compressor section. production F-111A was called the Triple Plow gross weight suffered accordingly. An increase The inlet design wasn’t entirely to blame. I, although further redesigns would appear on in unit cost from $US3 million to an estimated The TF30 was itself prone to compressor stall later models, as would improved versions of $US8-10 million was the final straw. Apart under certain circumstances and in combina- the TF30 itself. The engine went on to from which, the US Navy was never happy power all F-111s and also the F-14A Tomcat. about having what was a modified Air Force A simplified, non-afterburning version was bomber being forced upon it as a fighter! F-111B PRODUCTION fitted to US Navy Vought A-7A/B Corsair IIs As far as can be determined, the last 151970: First prototype, first flight 18 May 1965; and USAF A-7Cs. F-111B flight was conducted by the third TF30-P-3 engines; scrapped December 1969. aircraft (Bu151972) in mid-1971 from A SHORT LIFE to Lakehurst, New Jersey where it 151971: TF30-P-3 engines; testbed for Hughes Phoenix AAM; crashed into sea off California 11 The first five F-111Bs were regarded as was used for jet blast testing and then September 1968. prototypes, the initial three with individual scrapped at the end of the year. ejection seats rather than the definitive F-111 The cancellation of the F-111B sounded 151972: TF30-P-3 engines; damaged and withdrawn from use; repaired and ferried from California mid-1971 escape capsule in which the entire cockpit the death knell for Robert McNamara’s and used for jet blast testing at Lakehurst, New Jersey area with both crewmembers inside separated ‘procedural commonality’ theories. The (last F-111B flight); scrapped December 1971. from the rest of the airframe. The fourth and concept has reappeared more recently through 151973: TF30-P-3 engines; first with lightened airframe fifth prototypes featured lightened airframes the Lockheed Martin F-35 Joint Strike Fighter and crew escape capsule rather than individual ejection as the fact that the F-111B was seriously programme, and it has also had its share of seats.; crashed 21 April 1967 after double engine overweight became clear. cost, technical and schedule dramas. failure shortly after takeoff from Calverton, New Jersey Assembled by Grumman, the first of the Of significance was that the Hughes radar (ejection mechanisms failed, crew killed). seven F-111Bs (Bu151970) recorded its and Phoenix missile were not cancelled, and 151974: TF30-P-3 engines; lightened airframe; carrier maiden flight on 18 May 1965 from the their development continued. The US Navy trials aboard USS Coral Sea July 1968, only F-111B to manufacturer’s Long Island, New York, plant. got the fighter it had wanted all along when operate from carrier; landing accident NAS Point The sixth aircraft (Bu152714) was regarded deliveries of the superb Grumman F-14 Mugu, California 11 October 1968; scrapped 1970. as the first production representative F-111B. Tomcat began in June 1972, the prototype 152714: Pre-production with TF30-P-12 engines and It first flew on 29 June 1968 and featured a having flown in December 1970. Triple Plow II intakes; first flight 29 June 1968; used for lightened airframe, P-12 engines, improved The Tomcat combined three of the F-111B's Phoenix missile trials; retired 1969, struck off charge Triple Plow II intakes and flap and leading main elements – variable-sweep wings, TF30 1971 and used for parts; noted at scrapyard Mojave, edge slat modifications designed to lower the engines (initially) and the AWG-9 radar/ California in 2008. approach speed. Aircraft number seven Phoenix missile combination – with a new, 152715: Pre-production; TF30-P-12 engines and Triple (Bu152715) was built to the same standard tandem two-seat airframe. Production reached Plow II intakes; retired and stored at China Lake, and used as a testbed for the Phoenix missile. 713, almost exactly the number of F-111Bs California. But by then it was too late. Congress halted originally planned. 152716-717: Under construction at time of F-111B funding in March 1968 following an Robert McNamara served as Secretary of cancellation but not completed (2 aircraft). unsuccessful battle to bring its weight down Defense until 1968. After that, he was 152623-152642/156971-156978: Construction not to a manageable level, an impossible task as it appointed president of the World Bank. started at time of cancellation (28 aircraft). turned out. The programme was formally