F/A-18 Hornet


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, and electronic jamming platform.
Design
The F/A-18 is a twin engine, mid-wing, multi-mission tactical aircraft. It is highly maneuverable, owing to its good thrust to weight ratio, digital fly-by-wire control system, and leading edge extensions (LEX). The LEX allow the Hornet to remain controllable at high angles of attack. The wing is a trapezoidal shape with 20-degree sweepback on the leading edge and a straight trailing edge. The wing has full-span leading edge flaps and the trailing edge has single-slotted flaps and ailerons over the entire span. Canted vertical stabilizers are another distinguishing design element, one among several other such elements that enable the Hornet's excellent high angle-of-attack ability include oversized horizontal stabilators, oversized trailing edge flaps that operate as flaperons, large full-length leading edge slats, and flight control computer programming that multiplies the movement of each control surface at low speeds and moves the vertical rudders inboard instead of simply left and right. The Hornet's normally high angle-of-attack performance envelope was put to rigorous testing and enhanced in the NASA F-18 High Alpha Research Vehicle (HARV). NASA used the F-18 HARV to demonstrate flight handling characteristics at high angle-of-attack (alpha) of 65–70 degrees using thrust vectoring vanes. F/A-18 stabilators were also used as canards on NASA's F-15S/MTD.

The Hornet was among the first aircraft to heavily use multi-function displays, which at the switch of a button allow a pilot to perform either fighter or attack roles or both. This "force multiplier" ability gives the operational commander more flexibility to employ tactical aircraft in a fast-changing battle scenario. It was the first Navy aircraft to incorporate a digital multiplex avionics bus, enabling easy upgrades.
The Hornet is also notable for having been designed to reduce maintenance, and as a result has required far less downtime than its heavier counterparts, the F-14 Tomcat and the A-6 Intruder. Its mean time between failure is three times greater than any other Navy strike aircraft, and requires half the maintenance time. Its General Electric F404 engines were also innovative in that they were designed with operability, reliability and maintainability first. The engine, while unexceptional in rated performance, demonstrates exceptional robustness under various conditions and is resistant to stall and flameout. The F404 engine connects to the airframe at only 10 points and can be replaced without special equipment; a four person team can remove the engine within 20 minutes.
The engine air inlets of the Hornet, like that of the F-16, are of a simpler "fixed" design, while those of the F-4, F-14, and F-15 have variable geometry or variable ramp air inlets. This is a speed limiting factor in the Hornet design. Instead, the Hornet uses bleed air vents on the inboard surface of the engine air intake ducts to slow and reduce the amount of air reaching the engine. While not as effective as variable geometry, the bleed air technique functions well enough to achieve near Mach 2 speeds, which is within the designed mission requirements.
A 1989 USMC study found that single seat fighters were well suited to air to air combat missions while dual seat fighters were favored for complex strike missions against heavy air and ground defenses in adverse weather. The question being not so much as to whether a second pair of eyes would be useful, but as to having the second crewman sit in the same fighter or in a second fighter. Single-seat fighters that lacked wingmen were shown to be especially vulnerable
Variants
A/B
The F/A-18A is the single-seat variant and the F/A-18B is the two-seat variant. The space for the two-seat cockpit is provided by a relocation of avionic equipment and a 6% reduction in internal fuel; two-seat Hornets are otherwise fully combat-capable. The B model is used primarily for training. In 1992, the original Hughes AN/APG-65 radar was replaced with the Hughes (now Raytheon) AN/APG-73, a faster and more capable radar. A model Hornets that have been upgraded to the AN/APG-73 are designated F/A-18A+.
C/D
The F/A-18C is the single-seat variant and the F/A-18D is the two-seat variant. The D-model can be configured for training or as an all-weather strike craft. The "missionized" D model's rear seat is configured for a Marine Corps Naval Flight Officer who functions as a Weapons and Sensors Officer to assist in operating the weapons systems. The F/A-18D is primarily operated by the U.S. Marine Corps in the night attack and FAC(A) (Forward Air Controller (Airborne)) roles. The F/A-18C and D models are the result of a block upgrade in 1987 incorporating upgraded radar, avionics, and the capacity to carry new missiles such as the AIM-120 AMRAAM air-to-air missile and AGM-65 Maverick and AGM-84 Harpoon air-to-surface missiles. Other upgrades include the Martin-Baker NACES (Navy Aircrew Common Ejection Seat), and a self-protection jammer. A synthetic aperture ground mapping radar enables the pilot to locate targets in poor visibility conditions. C and D models delivered since 1989 also have improved night attack abilities, consisting of the Hughes AN/AAR-50 thermal navigation pod, the Loral AN/AAS-38 NITE Hawk FLIR (forward looking infrared array) targeting pod, night vision goggles, and two full-color (formerly monochrome) multi-function display (MFDs) and a color moving map.
In addition, 60 D-model Hornets are configured as the night attack F/A-18D (RC) with ability for reconnaissance. These could be outfitted with the ATARS electro-optical sensor package that includes a sensor pod and equipment mounted in the place of the M61 cannon. Beginning in 1992, the F404-GE-402 enhanced performance engine, providing approximately 10% more maximum static thrust became the standard Hornet engine. Since 1993, the AAS-38A NITE Hawk added a designator/ranger laser, allowing it to self-mark targets. The later AAS-38B added the ability to strike targets designated by lasers from other aircraft. Production of the F/A-18C ended in 1999. In 2000, the last F/A-18D was delivered to the U.S. Marine Corps.
E/F Super Hornet
The single-seat F/A-18E and two-seat F/A-18F Super Hornets carry over the name and design concept of the original F/A-18, but have been extensively redesigned. The Super Hornet has a new, 25% larger airframe, larger rectangular air intakes, more powerful GE F414 engines based on F/A-18's F404, and upgraded avionics suite. Like the Marine Corps' F/A-18D, the Navy's F/A-18F carries a Naval Flight Officer as a second crewman in a Weapons Systems Officer (WSO) role. The Super Hornet aircraft is in production and has equipped 22 squadrons.
The EA-18G Growler is an electronic warfare version of the two-seat F/A-18F, which entered production in 2007. The Growler will replace the Navy's EA-6B Prowler and carries a Naval Flight Officer as a second crewman in an Electronic Countermeasures Officer (ECMO) role. Australia is the only nation other than the United States to operate the Super Hornet.
Other US variants
F-18(R)
This was a proposed reconnaissance version of the F/A-18A. It included a sensor package that replaced the 20 mm cannon. The first of two prototypes flew in August 1984. Small numbers were produced.
RF-18D
Proposed two-seat reconnaissance version for the US Marine Corps in the mid-1980s. It was to carry a radar reconnaissance pod. The system was canceled after it was unfunded in 1988. This ability was later realized on the F/A-18D(RC).
TF-18A
Two-seat training version of the F/A-18A fighter, later redesignated F/A-18B.
F-18 HARV
Single-seat High Alpha Research Vehicle for NASA. High angles of attack using thrust vectoring, modifications to the flight controls, and forebody strakes
X-53 Active Aeroelastic Wing
A NASA F/A-18 has been modified to demonstrate the Active Aeroelastic Wing technology, and was designated X-53 in December 2006.

DISCLAIMER: The material content provided on this page is generated by another sources and consequently features user-generated content. While we do our best to stop offensive material appearing, ekotriyanggono.com cannot be held responsible for all of the material that may be displayed on this page. If you object to any article or picture, please leave us a comment in this page.

No comments:

Post a Comment