Aeropedia
McDonnell Douglas F-15
F-15
A F-15 banking left.

Role:

Air Superiority Fighter

Manufacturer:

McDonnell Douglas

First Flight:

July 27, 1972

Primary User:

United States Air Force Japan Air Self-Defense Force Royal Saudi Air Force Israeli Air Force

Number Built:

1,198

Unit Cost:

F-15A/B: $28 Million USD F-15C/D: $30 Million USD

The McDonnell Douglas (now Boeing) F-15 Eagle is a twin-engine, all-weather tactical fighter designed by McDonnell Douglas to gain and maintain air superiority in aerial combat. It is considered among the most successful modern fighters, with over 100 aerial combat victories with no losses in dogfights. The Eagle first flew in July 1972, and entered service in 1976. Since the 1970s, the Eagle has been exported to Israel, Japan, Saudi Arabia, and other nations. The F-15 was originally envisioned as a pure air superiority aircraft. Its design included a secondary ground-attack capability that was largely unused. The design proved flexible enough that an all-weather strike derivative, the F-15E Strike Eagle, was later developed, and entered service in 1989. The F-15 Eagle is expected to be in service with the U.S. Air Force past 2025. F-15 versions are still being produced for foreign users, with the F-15 production line set to end in 2019, 47 years after the type's first flight.

Development[]

Origins[]

Following studies conducted between 1964-1965, the U.S. Air Force developed requirements for a new air superiority fighter. Then the Air Force issued a request proposals for the new fighter aircraft. 2 major capabilities the aircraft must have was air-to-air and ground attack. Eight companies responded with proposals. In the following study phase, four of these companies developed some 500 design concepts. Typical designs featured variable-sweep wings, weighed over 60,000 lb (27,200 kg), included a top speed of Mach 2.7 and a thrust-to-weight ratio of 0.75. The designs were not accepted by the Air Force as they compromised fighter qualities for ground attack qualities. Acceptance of the Energy-Maneuverability (E-M) theory by the Air Force led to a change in requirements for improved maneuverability by the spring 1967. The design mission weight was reduced to 40,000 lb (18,100 kg), top speed reduced to Mach 2.3–2.5 and thrust-to-weight ratio increased to 0.97.

In 1967 U.S. intelligence was surprised to find that the Soviet Union was producing a large fighter aircraft, the MiG-25 'Foxbat'. It was not known in the West at the time that the MiG-25 was designed as a high-speed interceptor, not an air superiority fighter, so its primary asset was speed, not maneuverability. The MiG-25's huge tailplanes and vertical stabilizers hinted at a very maneuverable aircraft, which worried the Air Force that its performance might be better than its U.S. counterparts. In reality, the MiG's large fins and stabilators were necessary to prevent the aircraft from encountering inertia coupling in high-speed, high-altitude flight.

The McDonnell Douglas F-4 Phantom II of the USAF, U.S. Navy and U.S. Marine Corps was the only fighter with enough power, range, and maneuverability to be given the primary task of dealing with the threat of Soviet fighters while flying with visual engagement rules. As a matter of policy, the Phantoms could not engage targets without positive visual identification, so they could not engage targets at long ranges, as designed. Medium-range AIM-7 Sparrow missiles, and to a lesser degree even the AIM-9 Sidewinder, were often unreliable and ineffective at close ranges where it was found that guns were often the only effective weapon. The Phantom did not originally have any guns or cannons, but experience in Vietnam led to the addition of an internally mounted cannon in later versions.