F-4 Phantom II - History

Under its own financing and initiative, McDonnell Aircraft began developing an all-weather attack fighter in August 1953, shortly after it lost a competitive bid to build a Navy supersonic air-superiority fighter. McDonnell had already produced more than 1,000 carrier-based jet aircraft, the FH-1 Phantom, the F2H Banshee and the F3H Demon.

The McDonnell FH-1 Phantom, which made its first flight on January 26, 1945, was first operated from a carrier in the summer of 1946, and entered squadron service in 1948. The aircraft was conventional in design and employed an unswept wing with simple high-lift devices; manual flight controls were provided about all three axes. Mounted in the wing roots were the two 1560-pound-thrust Westinghouse axial-flow jet engines. Although not visible in the photograph, the inlets were located in the leading edge of the wing roots. Because newer aircraft had much superior performance, the short service life of the FH-1 ended in 1950.

The Phantom II traces its history back to September 1953, when McDonnell Aircraft Corporation submitted an unsolicited proposal for the F3H-G, a single-place, long-range fighter/attack aircraft, designed as an improvement of the Phantom. H.D.Barkey, Vice President, Aircraft Engineering Division, McDonnell Douglas Aircraft Co., St. Louis, Missouri, has emphasized that "The Phantom had its beginning not by winning an aircraft competition, but rather by losing one." Early in 1953, the Navy had conducted a competition for a carrier-based fighter plane which was won by the Chance-Vought F8U.

Mr. McDonnell, Chairman of McDonnell Aircraft, and his assistant, David Lewis (later Chairman of General Dynamics Corp.) were determined that the McDonnell Co. was not going to be forced out of the carrier-based aircraft business. They therefore embarked upon a prolonged marketing campaign, in which McDonnell engineers canvassed many Navy personnel in the Bureau of Aeronautics, the Office of the Chief of Naval Operations, and indeed anyone who was willing to listen and provide information or fill in questionnaires regarding their preferences for the next carrier-based fighter aircraft. There were many studies and layouts made during the following year; indeed, a full-scale mockup was constructed of a design which was then believed to be most nearly representative of the desires of the majority of Navy operations personnel contacted. That model ultimately became the F-4.

The company focused on developing a single-seat aircraft with 45-degree swept wings to replace the Demon. McDonnell worked on a design first designated the F3H-G and then the AH-1. Although there was no established military requirement for the aircraft, the Navy released details of a desired mission: an aircraft to be deployed from a carrier, armed with air-to-air missiles instead of guns, that could cruise out to a radius of 250 nautical miles, stay on combat patrol, attack an intruder when necessary, and return to the carrier deck within three hours.

McDonnell reconfigured the AH-1, removing the guns, adding Sparrow missiles, and substituting more powerful engines. The combined thrust of the GE J-79 engines would allow the F-4 to climb straight up after takeoff and give the Navy its first Mach 2 aircraft. Since the Navy was undecided about an aircraft with 1 or 2 places, the company designed both versions.

A formal development proposal was submitted to the US Navy by McDonnell in August 1954. The Phantom II was to be a single-place, but twin J65 powered, all-weather fighter armed with four 20mm cannons. The basic layout was similar to that of the Phantom I (the first jet-powered carrier fighter aircraft), the F2H Banshee series, and the Air Force F-101 Voodoo. The twin engines were expected to improve reliability and reduce attrition in both peace and war. Various structural and aerodynamic refinements were introduced, based on prior experience.

Particular attention was focused on the horizontal tail, which was ultimately given a negative dihedral mounted low on the fuselage in order to prevent the pitchup problems experienced with the F-101. Indeed, the tail design turned out to be one of the most difficult tasks in the development of the F-4.

In mid-1955 the full-scale engineering mock-up of the twin-engine aircraft featured a swept wing with no dihedral, and the horizontal tails drooped down at an angle of 15 deg. At the request of the Navy, tests began in the NASA Langley Unitary Plan Wind Tunnel to determine the supersonic performance and stability and control characteristics of the original configuration. Results of the first phase of tunnel tests indicated that the F4H exhibited serious deficiencies in lateral-directional stability characteristics at supersonic speeds, including unstable dihedral effect and marginal directional stability. To cure these problems, McDonnell introduced 12 deg of geometric dihedral into the outer wing panels (which were foldable for carrier operations) and increased the size of the vertical tail.

A major improvement was the installation of a variable-geometry engine air inlet which permitted good engine performance at all speeds and altitudes, and allowed the top speed to exceed Mach 2. The engine originally specified as the J-65 was replaced by the J-79 as socn as the latter was available, marking the usual history of fighter development in which improved performance engines are installed as early as possible.

General Electric made better progress than anticipated with the J-79, and early in 1955 it replaced the J-65. In October 1954, the Navy issued a Letter of Intent for the development of two prototypes and one static test aircraft, which were redesignated as the AH-I, reflecting the attack mission.

Following receipt of the Letter of Intent, Mr. McDonnell withdrew from direct participation in the project, which he turned over to David Lewis. Lewis worked with the Bureau of Aeronautics in an attempt to prepare a detailed specification for the AH-1. This was a very difficult assignment, as there was then no military requirement for the aircraft. After six months of futile attempts, the requirement was finally decided upon in the course of a 2-hour meeting at the McDonnell Aircraft plant in St. Louis, in April 1955. The mission was determined to be primarily fleet air defense: that is, the plane was to be deployed from a carrier, cruise out to a radius of some 250 nautical miles, stay on combat air patrol, attack an intruder when required, and then return to the carrier with a total deck cycle time of 3 hours. It was also determined that the airplane should be armed with air-to-air missiles of the latest type instead of guns. Specifications were firmed up and delivered to McDonnell in the form of a letter 9 months later.

Interestingly, the Navy admirals made their decision based on oaly three views and an inboard profile of the proposed airplane. There were no formal papers or other procedures such as are currently employed in the contract definition or concept formulation of a new aircraft weapon system. Indeed, the entire McDonnell proposal amounted to only an 8- to 10-page report.

The project proceeded on a basis of mutual trust between McDonnell and the Navy Department. There was not even a formal program mpnager until the initial flying date when David Lewis was named McDonnell program manager. Navy organization was handled by the "Class-Des, Fighter" commander. There was no Pentagon program manager, such as was commonly employed later in the development of such aircraft.

The design of the F-4 was an iterative process throughout its history. That is, it was responsive to Navy requirements, and in turn, Navy requirements were responsive to technical capabilities. Design decisions were often informal, reflecting results of various meetings or even chance conversations, such as would now be prohibited under current DoD regulations.

For example, the story is told that the initial decision to employ two engines in the F-4 resulted from a conversation between a McDonnell engineer and the wife of a Navy pilot who remarked at one point during a friendly dinner that her husband was terrified of making carrier approaches in a single-engine aircraft.

The AH-1 designation was changed to F4H-1 on 26 May 1955, with the change of mission to a missile-armed fighter. A camera equipped reconnaisance version, to be known as the F4H-lP, was also planned. During the course of these developments, the fighter had been reconfigured as a two-place aircraft, permitting all-weather fleet air defense. However, the attack capability of the original design was retained, which later led to the Phantom II being a logical choice for the US Air Force Tactical Air Command.

The configuration of the aircraft evolved through the signing of the detail specifications in July 1955 when the primary mission for the 2-place Phantom became an all-weather fleet air defense aircraft, retaining the attack capabilities from earlier designs.

During the early development of the F-4 the Navy experienced a most serious technical setback elsewhere. Complete reliance had been placed upon the J-40 engine in other programs. Indeed, all the Navy's trans-sonic aircraft were originally planned around that single large turbojet engine, predicted at the time to have outstanding performance. But the J-40 did not live up to expectations and was finally cancelled. The Navy resorted to Air Force engines and initiated crash development programs to supply its own needs.

Alarmed by the collapse of its J-40 engine program, the Navy decided it would develop an alternative to the F4H-1 and the J-79 engine upon which it depended, to avoid the possibility of a similar situation developing. The Navy therefore, in August 1955, asked Chance-Vought to submit a proposal for an all-weather, missile only, single seat, single engine fighter, an improved version of the company's successful F8U-I, which was to be powered by the new J-75 engine built by Pratt and Whitney. Such a program, it was thought, would protect against the collapse of the J-79 and/or the F4H-I program, or a discovery that there were basic concepts in either that were not sound. It was the Navy's intention to bring both aircraft into operational service with the fleet, if warranted. Fortune smiled, and both the new aircraft and engine proved highly successful.

However, the Congress would not grant production funds for both aircraft, The Navy chose the Phantom II primarily. because of its two-man fleet defense advantage. The F-4's second engine was also considered an advantage from the reliability and effectiveness standpoints. Certain Navy civilian engineers who participated in the evaluation believe the cancelled F8U-3 eventually would have set even higher performance records than the Phantom II. Although the F8U-3 was not a prototype, its concurrent development with the F4H-I was a close approximation to the currently proposed fly-before-buy prototype competition.

In the eyes of the McDonnell engineers and executives, the F8U-3 was a direct competitor of what was to become the F-4. They believed it was intended "to keep McDonnell honest." McDonnell's reaction to the introduction of the F8U-3 was to accelerate their own design efforts, primary among which were increased propulsion and introduction of a rear cockpit flight capability. The McDonnell executives thought the F8U-3 possessed less air-to-ground capability, which they saw as a major reason for its failure in the subsequent competition with the F-4. In addition, 1he F-4 was designed with growth factor always in mind as a major influence on design. The McDonnell executives believed the F-4 always had much greater potential for growth than had the F8U-3.