McDonnell Douglas F/A-18 Hornet

Les F-18; F/A-18 sur Wikipedia.en

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The McDonnell Douglas (now Boeing) F/A-18 Hornet is a twin-engine supersonic, all-weather carrier-capable multirole fighter jet, designed to dogfight and attack ground targets (F/A for Fighter/Attack).

Designed by McDonnell Douglas and Northrop, the F/A-18 was derived from the latter's YF-17 in the 1970s for use by the United States Navy and Marine Corps. The Hornet is also used by the air forces of several other nations.

It has been the aerial demonstration aircraft for the U.S. Navy's Flight Demonstration Squadron, the Blue Angels, since 1986.

The F/A-18 has a top speed of Mach 1.8. It can carry a wide variety of bombs and missiles, including air-to-air and air-to-ground, supplemented by the 20 mm M61 Vulcan cannon.

It is powered by two General Electric F404 turbofan engines, which give the aircraft a high thrust-to-weight ratio.

The F/A-18 has excellent aerodynamic characteristics, primarily attributed to its leading edge extensions (LEX).

The fighter's primary missions are fighter escort, fleet air defense, Suppression of Enemy Air Defenses (SEAD), air interdiction, close air support and aerial reconnaissance.

Its versatility and reliability have proven it to be a valuable carrier asset, though it has been criticized for its lack of range and payload compared to its earlier contemporaries, such as the Grumman F-14 Tomcat in the fighter and strike fighter role, and the Grumman A-6 Intruder and LTV A-7 Corsair II in the attack role.

The F/A-18 Hornet provided the baseline design for the Boeing F/A-18E/F Super Hornet, a larger, evolutionary redesign of the F/A-18.

Compared to the Hornet, the Super Hornet is larger, heavier and has improved range and payload.

The F/A-18E/F was originally proposed as an alternative to an all-new aircraft to replace existing dedicated attack aircraft such as the A-6.

The larger variant was also directed to replace the aging F-14 Tomcat, thus serving a complementary role with Hornets in the U.S. Navy, and serving a wider range of roles including refueling tanker.

The Boeing EA-18G Growler electronic jamming platform was also developed from the F/A-18E/F Super Hornet.

Development

Origins

The U.S. Navy started the Naval Fighter-Attack, Experimental (VFAX) program to procure a multirole aircraft to replace the Douglas A-4 Skyhawk, the A-7 Corsair II, and the remaining McDonnell Douglas F-4 Phantom IIs, and to complement the F-14 Tomcat.

Vice Admiral Kent Lee, then head of Naval Air Systems Command (NAVAIR), was the lead advocate for the VFAX against strong opposition from many Navy officers, including Vice Admiral William D. Houser, deputy chief of naval operations for air warfare – the highest ranking naval aviator.

In August 1973, Congress mandated that the Navy pursue a lower-cost alternative to the F-14. Grumman proposed a stripped F-14 designated the F-14X, while McDonnell Douglas proposed a naval variant of the F-15, but both were nearly as expensive as the F-14.

That summer, Secretary of Defense Schlesinger ordered the Navy to evaluate the competitors in the Air Force's Lightweight Fighter (LWF) program, the General Dynamics YF-16 and Northrop YF-17.

The Air Force competition specified a day fighter with no strike capability.

In May 1974, the House Armed Services Committee redirected $34 million from the VFAX to a new program, the Navy Air Combat Fighter (NACF), intended to make maximum use of the technology developed for the LWF program.

Redesigning the YF-17

Though the YF-16 won the LWF competition, the Navy was skeptical that an aircraft with one engine and narrow landing gear could be easily or economically adapted to carrier service, and refused to adopt an F-16 derivative.

On 2 May 1975 the Navy announced its selection of the YF-17.

Since the LWF did not share the design requirements of the VFAX, the Navy asked McDonnell Douglas and Northrop to develop a new aircraft from the design and principles of the YF-17.

On 1 March 1977 Secretary of the Navy W. Graham Claytor announced that the F-18 would be named "Hornet".

Northrop had partnered with McDonnell Douglas as a secondary contractor on NACF to capitalize on the latter's experience in building carrier aircraft, including the widely-used F-4 Phantom II.

On the F-18, the two companies agreed to evenly split component manufacturing, with McDonnell Douglas conducting final assembly.

McDonnell Douglas would build the wings, stabilators, and forward fuselage; while Northrop would build the center and aft fuselage and vertical stabilizers.

McDonnell Douglas was the prime contractor for the naval versions, and Northrop would be the prime contractor for the F-18L land-based version which Northrop hoped to sell on the export market.

The F-18, initially known as McDonnell Douglas Model 267, was drastically modified from the YF-17.

For carrier operations, the airframe, undercarriage, and arrestor hook were strengthened, folding wings and catapult attachments were added, and the landing gear widened.

To meet Navy range and reserves requirements, McDonnell increased fuel capacity by 4,460 pounds (2,020 kg), by enlarging the dorsal spine and adding a 96 gallon fuel tank to each wing.

A "snag" was added to the wing's leading edge and stabilators to prevent a flutter discovered in the F-15 stabilator.

The wings and stabilators were enlarged, the aft fuselage widened by 4 inches (102 mm), and the engines canted outward at the front.

These changes added 10,000 lb (4,540 kg) to the gross weight, bringing it to 37,000 lb (16,800 kg).

The YF-17's control system was replaced with a fully digital fly-by-wire system with quadruple-redundancy, the first to be installed in a production fighter.

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