Profile – F-4 Phantom II

Spurred on by his various achievements with Martin and the other companies before them, McDonnell decided that he should form his own company. After successfully obtaining some financial backing, the fledgling McDonnell Aircraft Corporation was incorporated on 6 July 1939 in Maryland. However ‘. the actual business commenced in St. Louis, Missouri, with one employee, one typewriter, very limited funds and modest premises situated adjacent to Lambert Field, St. Louis. These premises consisted of a couple of rooms located on the second floor of a small building, rented from American Airlines. Despite a slow start contracts were obtained to supply parts for other aircraft manufacturers. The first aircraft to be produced was a batch of 39 Fairchild AT-21 Gunner twin-engined training aircraft for bomber crews. These were not constructed at St. Louis but at a plant furnished by the US Government in Memphis, Tennessee.

McDonnell Aircraft Corporation’s first design venture resulted in the twin-engined XP-67. A contract was signed in 1941 to produce two aircraft. First flight was on 6 January 1944 and the XP-67 was lost in an accident on its 26th flight eight months later. Following the accident, construction of the second aircraft ceased and the contract was terminated. The first McDonnell aircraft to reach quantity production was the FD-1 Phantom I, a twin-engined jet fighter for the US Navy. Following the signing of a contract on 7 April 1943 the prototype flew on 26 January 1945. By the time production ceased during May 1948 a total of 62 had been delivered. The Phantom I became the first US jet-propelled aircraft to operate from an aircraft carrier when on 21 July 1946 trials were carried out from the USS Franklin D. Roosevelt. An interesting departure from the other types to enter production was the small XF-85 Goblin parasite fighter. Intended to be carried aloft by large bombers such as the B-36, only two were made during 1948.

It was the success of the F2H Banshee which was to give McDonnell the boost they needed. The Banshee was the first McDonnell aircraft to enter large-scale production. The prototype flew on 11 January 1947 and by the time production was concluded on 31 October 1953 a total of 895 had been delivered. The expertise displayed in the design and production of the Banshee was to establish McDonnell as the most important contractor of naval fighters. The Banshee made an important contribution during the Korean conflict which further proved its effectiveness as a combat aircraft.

Hard on the heels of the Banshee came the F3H Demon. A total of 521 had come off the line when production ceased on 8 April 1960. This was a fairly ambitious design with its highly swept wing. Early versions were so underpowered that some were permanently grounded. Later versions incorporating a more powerful engine developed into highly effective fighters and served aboard carriers in the Mediterranean, Caribbean and Far East.

A real pacesetter was the F-101 Voodoo. which had its maiden flight on 9 September 1954. When it entered service with the USAF in 1957 it was the fastest operational jet in the world and the first to be utilised by the USAF Air Defence, Strategic and Tactical Air Commands at the same time. Numerous versions were developed over the years and by the time the last Voodoo was delivered on 3 March,1961 a total of 807 had been handed over.

The picture to emerge from these various designs was of a manufacturer rapidly gaining experience in the development of advanced aircraft. What was to follow as McDonnell’s next effort was to elevate them enormously as a builder of one of the “greats” of all time.

The irony of the Phantom II project is that it came about after McDonnell had been unsuccessful in gaining a contract to build a new carrier-based fighter for the US Navy. In a hard-fought contest, the winner was the Chance Vought F8U Crusader, selected in May 1953. This was a disappointment to McDonnell who had been working hard to build up expertise in the construction of naval fighters. The success of their previous models had led them to believe that they would have been the winners. Unfortunately for them, this did not happen so they set about formulating a proposal that they felt would make up for the loss to Chance Vought.

What McDonnell had in mind was to go out and capture a contract for the next generation of carrier-based fighters, the specification for which was of course undefined and the requirement itself was several years away. Designated the McDonnell Model 98, studies began of a twin-engined, very high-performance attack aircraft in the early part of 1953. Some months later the US Navy asked McDonnell to study further a single-seat attack version of the Model 98 incorporating APQ-50 X band pulse radar, four 20 mm cannon and a large number of external stores stations. The major purpose of the aircraft was to be an air-to-ground attack. The powerplants chosen were two Curtiss J-67 (US versions of the Armstrong-Siddeley Sapphire) with the potential to install the more advanced General Electric J79 which was under development.

Now known as the F-3H-G/H design, McDonnell submitted an unsolicited proposal to the then Bureau of Aeronautics for consideration on 19 September 1953. In an effort to determine what was required, McDonnell engineers canvassed the opinion of Navy operations personnel, the Bureau of Aeronautics (BuAer), the Chief of Naval Operations for Air (CNO), and other interested parties. They were invited to return questionnaires outlining, in their opinion, what was wanted in the next generation of carrier-based fighters. An analysis was made of the feedback obtained and in 1954 a full-scale mock-up was constructed of the aircraft which was believed to best represent the consensus of opinions submitted.

Following this, invitations were sent to several Navy operating commands, BuAer, CNO, and other specialist areas requesting their comments on the mock-up. At this point although some similarities were evident with the later Phantom, the mock-up was of a streamlined single-seat aircraft. The wings and horizontal tail were flat, devoid of the characteristic shapes which were later to develop. Concurrent with all this work, on 15 June 1954 the BuAer made known the need for an all weather aircraft. Proposals considered by the Navy were the F3H-G/H, F3H-E2 (single-engined version), and submissions from Grumman and North America. The winner was the F3H version powered by two J79 engines. On 18 October 1954, a letter of intent was placed with McDonnell for the construction of two prototypes and a static test aircraft similar to the mock- up, to be redesignated as the AH-1. Following receipt of the letter of intent, negotiations with BuAer continued in an attempt to prepare a detailed specification of the AH-1.

In 1955 a major change was made in the role of the aircraft. Following a meeting between the US Navy and McDonnell the principal mission was changed from an attack to an all-weather air-to-air mission while still retaining the basic capability for nuclear and conventional weapons attack. The basic mission outlined by the Navy was for the aircraft to be deployed from a carrier, cruise out to a radius of 250 nautical miles, stay on combat air patrol attack an intruder when required, and return to the carrier with a total cycle time of 3 hours. After two weeks of feverish activity, the design was reconfigured in accor- dance with the Navy’s wishes. The guns were removed and were replaced by semi-submerged Sparrow III missiles located in recesses in the lower surface of the fuselage. Mounting the missiles in this way results in low drag and does not take up a large volume. within the fuselage. The missiles are launched downwards by explosive charges after which they depart under their own power.

Following the changes in the primary mission the designation was changed to the F-4H-1 to more accurately reflect its redefined role. Many other alterations were made and were incorporated in the detailed specifications signed in July 1955. Amongst these were the changing of the fire control system to be compatible with air-to-air missiles and, the removal of all external armament stations except the centreline one under the fuselage retained for the carriage of a large external fuel tank. Other features of the specification were: fitting of J79 power- plant, improved A. I. radar, a single lightweight semi-automatic navigation device, visual ground attack capability, a maximum speed of at least Mach 2 with missile armament, and two-man crew.

On the question of crew, there were supporters of both schools of thought as to whether naval aircraft of this type should be single-seat or two-seat. McDonnell prepared both single and two-seat layouts which were identical except that the two-seat version had a 150-gallon fuel cell removed from the forward fuselage to provide space for the second crew member. To enable the existing range to be retained this displaced fuel was accommodated in the external centreline tank which was increased in size by approximately the same volume. Both versions were submitted to the BuAer and CNO for their consideration and within 36 hours the Navy opted for the two-seat configuration and had advised McDonnell of their decision. In an effort to ensure that they got the best product the Navy invited Chance Vought to construct an aircraft for the same mission requirement. Chance Vought set about their task and came up with the single-engine, single-seat, missile-carrying F8U-3.

Detailed wind tunnel testing was undertaken by McDonnell to refine the aerodynamic layout. Over 5000 hours were spent in wind tunnel research to arrive at the optimum aerodynamic shape. Construction of the first F4H-1 began during August 1956. The magnitude of the program can be illustrated that by the time construction of the first prototype had been completed more than 6,800,000 man-hours had been devoted to design and construction. Approximately 1500 subcontractors and suppliers from 28 States participated in the project.

During the period of construction, the specification was upgraded, mainly because of the change from AH-1 to F4H-1 configuration. Apart from the alterations previously mentioned the following additional major changes were implemented.

1. Catapulting under zero wind, military power conditions.

2. Increased use of titanium.

3. Revised strength criteria.

4. Steerable dual nose wheels (provisions).

5. Provision for temporary use of J79-GE-3 engine with diffefent requirements from the J79-GE-2 that will ultimately be used.

6. External tanks and provision for buddy refuelling added.

7. Production, in lieu of experimental type tooling.

8. Increased structure and systems equipment complexity.

9. More extensive flight test program.

The culmination of all this effort was the first flight at St. Louis of the YF4H-1 prototype on 27 May 1958 with Robert C. Little at the controls. At the time of the flight, the development program centring on the powerplant had advanced to the stage where it was intended that the J79-GE-8 be fitted. However as none were as yet available a pair of J79-GE-3A engines of 9300 lb thrust each were borrowed from the USAF. The excellence of the basic design is evident when one considers that the external aerodynamic configuration has not changed since that first flight.

After McDonnell test pilots completed initial flights of the prototype the Navy Preliminary Evaluation (NPE) began. These evaluations are divided into five basic phases which are designed to detect problem areas during early development stages. The Phase I NPE was conducted at Edwards Air Force Base and at St. Louis between 15 September and 10 October 1958. In addition, pilots from the Naval Air Test Center at Patuxent River made a total of 43 flights during this period.

It was during this time that intense competition took place between the F4H-1 and the F8U-3 during the NPE at Edwards AFB. Navy pilots flew both aircraft side by side and were able to make direct comparisons in performance. The result in this competition was crucial to McDonnell who had lost out to the earlier F8U-1 some years earlier. One can imagine their delight when the F4H-1 was announced as the winner. Several reasons were advanced for the F4H-1’s superiority in the contest. Amongst these were the two-place, twin-engined layout. It was proven that a full-time radar observer improved radar detection probability, greatly enhancing the overall handling of the weapons systems. McDonnell was jubilant about the outcome and the Phantom was on its way to becoming a significant part of aeronautical history. The first contract signed in December 1958 was only a foretaste of the substantial orders to follow.

Even at this stage, the F4H was a formidable aircraft. To show off its capabilities on 6 December 1958 with Commander Lawrence Flint at the controls the prototype YR4H-1 took off from Edwards AFB on Project Top Flight. The aim of the mission was to establish a new absolute altitude record. The prototype reached an altitude of 98,557 feet during its successful record attempt.

During the Phase II NPE conducted at Edwards AFB and NATC Patuxent River during July and August 1959, the speed altitude envelope was expanded and field-carrier landings, mirror approaches and wave-off capabilities were evaluated. It was during this time, on 3 July 1959, that McDonnell officially gave the name Phantom II to the aircraft at a ceremony during the celebration of the Company’s 20th anniversary. Phase Ill involved the evaluation of the automatic flight control system and the inflight refuelling system. Phase IV was mainly devoted to the evaluation of the production of electrical and electronic equipment installed in the aircraft whilst the final phase V NPE involved the demonstration of the ground attack capabilities.

Having been subjected to these rigorous tests, the way was now clear to see how the Phantom performed from its intended operational base, the aircraft carrier. Sea trials began with the first catapult take-off and landing on 5 February 1960 aboard USS Independence off the coast near Jacksonville, Florida. Intensive testing continued during 1960 and by July the Board of Inspection Survey commenced at Patuxent River. These trials accelerated the testing of aircraft performance, stability and control and further checked out its carrier suitability. The performance of the Phantom in its intended mission proved outstanding. Some discrepancies in individual systems were uncovered, not unusual in so complex an aircraft, and were subsequently corrected.

Amongst many noteworthy features of the Phantom II is its overall appearance. Certainly, few of its contemporaries have such a rugged distinctive stance. The rakish lines of the aircraft seem to give it an air of aggressiveness. Similarities with earlier McDonnell aircraft are obvious. But despite several parallels, the Phantom was very much a new aircraft. The overall arrangement of the wings, fuselage and empennage was primarily dictated by aerodynamic necessities, but subject to structural, operational and maintenance considerations. Theoretical calculations, results of extensive wind tunnel testing and flight experience gained with the Banshee, Demon and Voodoo all contributed to the determination of the final layout.

The angle of sweepback of the wing is similar to the Demon but it has a lower thickness ratio to match its higher speed. The sharp taper in the planform gives a near delta look, and there is a discontinuity in the leading edge at the wing fold where the outer panel chord has been increased 10% over the basic planform. This interruption in the leading edge creates a swirl of air on the upper surface at modest angles of attack which inhibits complete stalling of the airflow on the outer panel.

Positioning of the wing low on the fuselage was done in order to keep the landing gear reasonably short while allowing enough clearance to carry wing-mounted tanks and armament. The main part of the wing carries straight through the fuselage for greater strength and for ease of assembly. The outer wing panels have a 12-degree dihedral incorporated to offset a negative dihedral effect resulting from the wing being mounted low on the fuselage. Only the outer panels were bent up in order to preserve the straight-through wing structure, and the bend itself was conveniently made at the wing fold.

Several movable surfaces are built into the wings. Both leading and trailing edge flaps are utilised to create as much lift as possible during take-off and landing. Spoilers and ailerons are employed to provide lateral control at both high and low speeds. It was possible to place the spoilers directly in front of the ailerons since, on a given wing, only one surface operates at a time (either a spoiler goes up or an aileron goes down during a roll). Speed brakes are mounted under the wing ahead of the trailing edge flaps. They are more effective in this location in providing more drag per square foot than the more common aft fuselage types.

One of the most striking features is the non-horizontal “horizontal” tail. This thin, swept, highly tapered, all-moving surface has approximately 23 degrees of negative dihedral. Mounting the tail in this manner aligns it properly with the swirling airstream which exists at moderate angles of attack, thus avoiding the usual stability reduction associated with swept-wing aircraft.

It is the fuselage that appears somewhat out of kilter with the performance attained by the Phantom II. Aerodynamic theory would seem to dictate a long, slim fuselage with a needle-like nose. The fuselage is actually three feet shorter than the single-engined Demon in order to allow for improved deck handling on carriers. The need to house two large engines, together with the associated air inlets, four semi-recessed missiles, the complex electronic equipment, and large quantities of fuel has resulted in a rather short stubby fuselage that looks somewhat out of character for a very fast supersonic fighter. However, this has all been cunningly done. In order to reduce drag due to skin friction only a minimum of openings and protuberances mar the surface. The two-man cockpit has been depressed as much as possible since the shape of the forward part of the fuselage is very important at supersonic speeds. An arresting hook is nicely faired into the centreline keel at the fuselage aft of the jet tailpipes. At the extreme end of the fuselage just below the rudder is the compartment housing the drag parachute used to decelerate during field landings and as a possible spin recovery device.

The engine air inlets are placed several inches out from the fuselage in the same manner as the Voodoo to avoid the slow moving air next to the fuselage. These carefully designed inlets are sophisticated devices to ensure the optimum air flow· is induced through the intake. Movable “control surfaces” or ramps are located just ahead of the inlet and are automatically actuated. Their function is to turn the air outwards at supersonic speeds, thereby compressing it before it enters the inlet. The upstream ramp is fixed but the angle of the movable ramp to the airstream varies with Mach number and air temperature. Low energy air which builds up on the ramp surfaces is sucked off through a gap between the first and second ramps and through the perforations (12,500 of them per side) on the second ramp. This air is then expelled through the louvres above the inlets. When the ramp moves it varies the amount of compression and also the size of the inlet area. Further rationing of the air to the engines takes place near the engine face when some air is bypassed around the engine, cooling it and exiting through the rear of the engine between the nozzle and shroud. In the process, this bypass air forms the expansion portion of the engine’s supersonic jet nozzle.

The eventual success of the Phantom II must have far exceeded McDonnell’s brightest hopes. Expectations in December 1958 were for sales of 375 aircraft to the US Navy, deliveries of which were to spread over the next seven years. Initial production was of the F4H-1F powered by the J79-GE-2 or 2A of 10,350 lb thrust (15,900 lb with afterburning). The F suffix was used to indicate the use of a special powerplant. The first 18 aircraft had a flush canopy and 24 inch radar antenna for the APQ-72 Westinghouse radar. These aircraft were used for development testing. To improve radar performance a larger 32 inch antenna was fitted. As this resulted in a larger nose, the seats and canopy were raised to improve visibility. Aircraft 19 through 47 incorporated these modifications. The first production delivery was aircraft No. 28 which went to squadron VF-121, Naval Air Station Miramar on 29 December 1960. All the F4H-1F aircraft were assigned to test facilities and training squadrons (in the latter case they became known as the TF-4A). Eventually the intended J79-GE-8 of 10,900 lb thrust (17,900 lb with afterburning) became available and were installed in aircraft No. 48 onwards. These were known as the F4H-1. Other improvements were redesigned air inlets and strengthened landing gear. First flight of the prototype was on 13 May 1960 and the first production aircraft on 25 March 1961.

When a new Tri-Service designation system was introduced the designation of the F4H-1F was changed to F-4A in June 1962 and that of the F4H-1 to F-48. It was the F-48 that was to lay the foundation for the large increase in production yet to come. As a hint of orders to come several additional contracts were placed for F-4Bs which became the US Navy’s primary fleet air defence interceptor from 1962 until 1967. In addition, it was the US Marine Corps’s main aircraft for their all-weather fighter/attack squadrons. By the time the last F-48 had been delivered on 27 January 1967, a total of 634 had been produced. In addition, the Marines acquired 46 RF-48 aircraft (originally designated F4H-1P) which had a 4’8-7/8″ longer nose containing multiple sensor reconnaissance equipment. Single sideband high-frequency radio was later fitted.

The specialised equipment also consisted of either forward and side oblique cameras or a mapping camera, with an infra-red sensor and sideways-looking radar. An interesting capability was the capacity to develop film in flight and then to eject the cassettes when necessary to ground stations for rapid examination of the results. To aid night photography, photoflash cartridges were ejected upwards on both sides of the RF-48. All in all this was a most efficient information gatherer. The first RF-48 was initially flown on 12 March 1965 and the last was delivered on 24 December 1970. Conversion of 44 F-4Bs was made later resulting in the QF-48 drone aircraft. Twelve F-4Bs were production modified to become the F-4G. These had two-way data link for carrier landing. They were later converted back to F-48 configuration. Some of the later F-4Bs incorporated features embodied in the later F-4J such as drooped ailerons and slotted stabilator.

A further major rework was done on selected F-4Bs resulting in the F-4N. The first flight was on 6 April 1972. Significant improvements were a structural strengthening to improve fatigue life, complete rewiring, installation of30 KVA generators, one-way data link, air-to-air IFF, Visual Target Acquisition System . . (VTAS), Sidewinder Expanded Acquisition Mode (SEAM), automatic altitude reporting and the fitting of a dogfight computer. A total of 178 aircraft were so converted.

Some specifications of the F-4B are Span 38’4-7/8″, length 58’3-3/4″, height 16’3″, wing area 530 square feet, empty weight 28,000 lb, maximum weight 54,600 lb, maximum speed 1485 mph at 48,000 feet, cruising speed 575 mph, rate of climb 28,000 ft/min, ferry range 2300 miles.

It was the Phantom’s association with the US Air Force which was to provide a major stimulus to its fortunes. At the outset, McDonnell had designed the aircraft with the USN requirements specifically in mind. The USAF had been watching the Phantom’s progress with interest for some time. In November 1961 the F4H demonstrated itself to be superior to the Convair F-106. During the following month, the Department of Defense announced consideration was being given to the reconnaissance version of the F4H, to be designated the RF-110. In a series of swift developments, the Air Force moved to acquire Phantoms. The President’s Budget submitted to Congress in January 1962 requested procurement of the RF-110 and the fighter version of the F4H, the F-110A. Two F-110 aircraft were delivered to TAC headquarters at Langley Air Force Base and the first contract for the F-110A was signed in April and for two prototype RF-110A aircraft in May.

The US Air Force’s purchase of Phantoms broke new ground as it was the first time they had obtained an aircraft that had been designed primarily for operations from aircraft carriers. During September 1962 these aircraft were redesignated RF-4C and F-4C. Although the F-4C has 92% commonality with the USN F-4B on which it is based, there are several major differences. To enable the F-4C to be more suitable for Tactical Air Command use, certain changes were made to suit its dual role as an air superiority fighter and ground attack aircraft. Cartridge engine starters were fitted to enable it to have the ability to operate from remote fields. Dual control was installed in the rear cockpit, boom flight refuelling was substituted for the Navy’s drogue system to enable it to be compatible with Air Force tankers. Larger wheels and tyres (30″ x 11. 5″) with anti-skid brakes were fitted so it could cope better with asphalt runways. Numerous electronic changes included ASN-48 Inertial Navigation System to permit long-range independent navigation, APQ-100 radar with radar scopes in both cockpits, AJB-7 all altitude bomb control system, an ASN-46 navigation computer and an APA-157 radar set group.

Despite these modifications, many items were unchanged.

Two interesting retentions were the folding wings and arrester gear. The two J79-GE-15 engines had a similar power output to the engines installed in the Navy’s F-4Bs. Armament was based on four Sparrow Ill missiles with no built in guns being fitted. A large variety of external weaponry included bombs of various types, gun pods and/or mines, and air-to-air or air-to-ground missiles. The maximum external load was 16,000. The first flight was on 27 May 1963 with William S. Ross as the pilot and Robert C. Little in the rear cockpit. Initial squadron delivery was to TAC, MacDill Air Force Base, Tampa, Florida on 20 November 1963. When the last F-4C was handed over to TAC on 4 May 1966 a total of 583 had been produced. Of these 36 were exported to Spain.

The RF-4C reconnaissance version was also produced in large numbers. The first research and development flight of the prototype YRF-4C (originally RD-110) with William S. Ross as the pilot and B. A. McIntyre as the radar operator was on 9 August 1963. The forward fuselage was redesigned to house the optical and electronic equipment necessary to perform the tactical reconnaissance mission. The missile control system was removed. Performance was similar to the F-4C. A total of 505 was delivered with the last aircraft being handed over on 16 January 1974.

Some details of the RF-4C are as follows: Span 38’4-7/8″, length 62’10-7/8″, height 16’6″, empty weight 28,276 lb, max weight 58,000 lb, max speed 1459 mph at 40,000 ft, service ceiling 59,400 ft, rate of climb 48,300 ft/min, ferry range 1750 miles.

The next Phantom to enter USAF service was the F-4D. This was an updated version of the F-4C and had essentially the same airframe and engines. Major system improvements were made to increase the aircraft’s air-to-ground weapon delivery accuracy and air-to-air gunnery capability. Other changes were the addition of a Lead Computing Optical Sight, a Weapon Release Computer set, and modifications to the radar that included air-to-ground ranging and movable cursors. First flight was on 12 August 1965 and 825 had been delivered when production terminated in 1968. Of these 757 went to the USAF, 32 to the Imperial Iranian Air Force and 36 to the Republic of Korea Air Force.

(Next Issue: We continue the Phantom saga with the entry to service of the F-4E.)