History
Advanced Tactical Fighter (ATF) is a contract for the demonstration and validation program by the United States Air Force to develop a new generation air superiority fighter to deal with threats from outside the United States, including the development of class aircraft Su-27 Soviet era.
In 1981, the United States Air Force to map the requirements to be fulfilled a new fighter aircraft that is planned to replace the F-15 Eagle. ATF planned to integrate modern technology such as advanced metal and composite materials, sophisticated control systems, high-powered propulsion systems, and stealth aircraft technology.
Proposals for the contract was filed in 1986, by two contractor teams, the Lockheed-Boeing-General Dynamics and Northrop-McDonnell Douglas, who was elected in October 1986 for the demonstration and validation phase for 50 months, which eventually produced two prototypes, the YF -22 and the YF-23.
The aircraft is planned to be the most advanced U.S. aircraft at the beginning of the 21st century, therefore, this plane is the most expensive fighter aircraft, with a price of U.S. $ 120 million per unit, or U.S. $ 361 million per unit when it is added to the cost of development. In April 2005, the total development cost of this program is U.S. $ 70 billion, causing the number of aircraft planned to be made down to 438, then 381 and now 180, from the initial plan of 750 aircraft. One of the factors causing this reduction is due to the F-35 Lightning II will have the same technology with the F-22, but with a cheaper unit price.
YF-22 'Lightning II'
YF-22 is a plane development is the basis for the manufacture of F-22 production version. However, there are some significant differences between the two, which changes the position of the cockpit, structural changes, and many other small changes. Both aircraft are often mixed up in the photographs, usually at the point of view that is difficult to see certain features. YF-22 Lighting II are given nicknames by Lockheed, this name lasted until the mid-1990s. For some time, this plane also was given the nickname SuperStar and Rapier. But the F-35 and then officially received the name of Lighting II on July 7, 2006.
YF-22 ATF awarded after winning a competition to fly to beat Northrop YF-23 made by McDonnell-Douglas. In April 2002, at the time of testing, the first YF-22 prototype crashed while landing at Edwards Air Force Base in California. The test pilot, Tom Morgenfeld, was not hurt. The cause of this fall is a fault in the software.
Production
F-22 production version first sent to Nellis Air Force Base, Nevada, on January 14, 2003. Testing and final evaluation conducted on October 27, 2004. In late 2004, already there are 51 Raptor is sent, with 22 more booked in the 2004 fiscal budget. The destruction of the first production version occurred on December 20, 2004 at the time of takeoff, the pilots eject safely after a few moments before it crashed. Investigating this fall concluded that interruption of power when turned off the engine before take-off causing damage to the controversial system
Change of name
Production version of the aircraft is named the F-22 Raptor when it was first raised on April 9, 1997 at Lockheed-Georgia Co.., Marietta, Georgia.
In September 2002, the United States Air Force officials to change the name of the F/A-22 Raptor. The naming of this, which is similar to the naming of F/A-18 Hornet U.S. Navy, aims to promote the image of Raptor fighter aircraft as well as ground attack aircraft, due to the debate that occurred in the U.S. government about the importance of air superiority fighter that is very expensive. The name is then returned again to the F-22 alone on December 12, 2005, and then on December 15, 2005 F-22A officially began to be used.
Purchase
United States Air Force originally planned to order 750 ATF, with production starting in 1994. In 1990 Major Aircraft Review to change the plan to 648 aircraft beginning in 1996. The ultimate goal changed again in 1994, to 442 aircraft entered the life in 2003 or 2004. Report Ministry of Defence in 1997 to change the purchase to 339. In 2003, the Air Force said that the existing congressional funding restrictions now limit the purchase to 277. In 2006, the Pentagon said it would buy 183 aircraft, which will save $ 15 billion but would increase funding per aircraft. This plan has been approved by the de facto of Congress in the form of purchase plan several years, which is still open opportunities for new orders past that point. Lockheed Martin has said that in FY (Fiscal Year / FY) 2009 they already have to know whether more planes would be purchased, for ordering the goods of long-lead.
In April 2006, the cost of the F-22A estimated by the Government Accountability Office to be $ 361 million per plane. These costs reflect the total cost of the program F-22A total program cost, divided by the number of jets to be purchased by the Air Force. So far, the Air Force has invested as much as $ 28 billion in research, development, and experiments Raptor. That money, referred to as a "sunk cost," has been spent and is separate from money used for future decision making, including the purchase of coffee from the jet.
When all 183 jets have been purchased, $ 34 billion will be spent to purchase these aircraft really are. This will result in cost about $ 339 million per aircraft based on the total cost of the program. The increase in the cost of one additional F-22 is about $ 120 million. If the Air Force would buy 100 additional F-22 today, each plane would cost less than $ 117 million and will continue to fall with additional aircraft purchases.
F-22 is not the most expensive aircraft ever; peculiarity seemed to die on the B-2 Spirit, which is roughly worth $ 2.2 billion per unit, although the cost increases below 1 billion U.S. dollars. For more fair, booking B-2 went from hundreds to a few dozen when the Cold War ended, so the price per unit soar. F-22 uses fewer radar absorbent materials than the B-2 or F-117 Nighthawk, with the hope that treatment costs will be lower.
Characteristic
Movement
Dual turbofan engines Pratt & Whitney F119-PW-100 F-22 has a thrust steering capability. Steering can adjust the rotation axis pitch to about 20 °. Maximum thrust of this engine is still kept secret, but estimated about 35,000 lbf (156 kN) per turbofan. The maximum speed the aircraft is estimated at Mach 1.2 when the supercruise without external weapons. With the afterburner, according to Lockheed Martin, the speed is "more than Mach 2.0" (2120 km / h).
F-22 also can maneuver very well in supersonic and subsonic speeds. The use of steering thrust makes a sharp turn, and perform extreme maneuvers such as Herbst Maneuver, Cobra Pugachev, [10] and Kulbit. F-22 also can maintain a constant attack angle greater than 60 °. Altitude flying also affect the attack. In a military exercise in Alaska in June 2006, F-22 pilots said that the ability to fly at higher altitudes than other aircraft is one of the determinants of the F-22 victory in the practice.
Avionics
F-22 uses AN/APG-77 AESA radar designed for the operation of air superiority and ground attack, which is difficult to detect aircraft opponent, using an active aperture, and can track several targets simultaneously in any weather. AN/APG-77 change frequency 1,000 times every second, making it also very difficult to track. This radar can also focus the emission of the sensor opponent, making the plane to crash opponent.
Information on this radar is processed by two Raytheon processors, each of which can perform 10.5 billion operations per second, and has 300 megabytes of memory. The software on the F-22 consists of 1.7 million lines of code, most of which are captured radar data processing. These radars have a range of about 125-150 miles, and is planned to be updated with a maximum distance of 250 miles.
F-22 has several unique functions for an aircraft its size. Among other things, this aircraft has the capability of detection and identification of an enemy that is almost equivalent to the RC-135 Rivet Joint.Kemampuan "mini-AWACS" This makes the F-22 is very useful on the front lines. This aircraft could indicate targets for the F-15 and F-16, and even to know what the plane was to target his plane, so it could make for his plane did not pursue the same target.
Bus data used aircraft, named MIL-STD-1394b, which is designed specifically for the F-22. Bus system was developed from the commercial system FireWire (IEEE-1394), which was created by Apple and is often found on an Apple Macintosh. Data bus system will also be used on fighter aircraft F-35 Lightning.
Weaponry
F-22 is designed to carry air-to-air missiles are stored internally in the fuselage so as not to interfere with the ability silumannya. Missile launch was preceded by a valve open arms and missiles driven down by the hydraulic system. This aircraft can also carry bombs such as Joint Direct Attack Munition (JDAM) and Small-Diameter Bomb (SDB) is more recent. In addition to internal storage, this aircraft can also carry weapons on four external point, but if it is used will greatly reduce the ability of stealth, speed, and agility. For backup guns, F-22s carry M61A2 Vulcan automatic cannon 20 mm stored in the right side of the plane, was carrying 480 cannon rounds, and will be discharged if fired continuously for about five seconds. Even so, the F-22 can use this gun when the fight without being detected, which will be needed when the missile has been exhausted.
The ability of stealth
Western modern fighter aircraft of today have used the features that make them more difficult to detect on radar than previous aircraft, such as the use of radar absorbing material. In the F-22, besides the use of radar absorbing material, shape and form F-22 is also designed, and other details such as the hook on the plane and pilot helmets have also been made for more hidden. F-22 is also designed to emit infra-red which is more difficult to track missiles "heat seekers".
However, the F-22 does not depend on radar absorbing material such as the F-117 Nighthawk. The use of this material could not bear to bring up the problem because of bad weather. And unlike airplane bomber B-2 Spirit stealth that require special hangars, the F-22 can be given usual care in the hangar. In addition, the F-22 also has a system called "Signature Assessment System", which will indicate when the aircraft radar tracks already high, until eventually require repairs and maintenance.
Use of afterburner also make aircraft emissions more easily captured by the radar, it is estimated is the reason why the F-22 is focused to be able to have the ability supercruise.
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