F 22 raptors over the pacific ocean |
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF. It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform.The Raptor has large shoulder-mounted trapezoidal wings, four empennage surfaces, and a retractable tricycle landing gear. Flight control surfaces include leading and trailing-edge flaps, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails; these surfaces also serve as speed brakes.
The aircraft's dual Pratt & Whitney F119-PW-100 afterburning turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class.The F-22's thrust to weight ratio in typical combat configuration is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is estimated to be Mach 1.82 during supercruise and greater than Mach 2 with afterburners.
The F-22 is among only a few aircraft that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; targets can be intercepted which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The Raptor's high operating altitude is also a significant tactical advantage over prior fighters. The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The F-22's structure contains extensive amounts of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the aircraft's structural weight.
An Air Force F-22 Raptor executes a supersonic flyby over the flight deck of USS John C. Stennis |
The F-22 is highly maneuverable at both supersonic and subsonic speeds. Computerized flight control system and full authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable at aggressive pilot inputs.The Raptor's relaxed stability and powerful thrust vectoring powerplants enable the aircraft to turn tightly and perform very high alpha (angle of attack) maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The aircraft is also capable of maintaining over 60° alpha while having some roll control.
The Raptor's aerodynamic performance, sensor fusion, and stealth work together for increased effectiveness. Altitude, speed, and advanced active and passive sensors allow the aircraft to spot targets at considerable ranges and increase weapons range; altitude and speed also complement stealth's ability to increase the aircraft's survivability against ground defenses such as surface-to-air missiles
WEAPONS
For stealth, the F-22 carries weapons in internal bays. The doors for the center and side bays are open note the six LAU-142/A AMRAAM Vertical Eject Launchers (AVEL). |
The Raptor has three internal weapons bays: a large bay on the bottom of the fuselage, and two smaller bays on the sides of the fuselage, aft of the engine intakes. The main bay can accommodate six LAU-142/A launchers for beyond-visual-range missiles and each side bay has an LAU-141/A launcher for short-range missiles.Four of the launchers in the main bay can be replaced with two bomb racks that can each carry one 1,000 lb (450 kg) or four 250 lb (110 kg) bombs. Carrying armaments internally maintains the aircraft's stealth and minimizes additional drag. Missile launches require the bay doors to be open for less than a second, during which hydraulic arms push missiles clear of the aircraft; this is to reduce vulnerability to detection and to deploy missiles during high speed flight.
The F-22 can also carry air-to-surface weapons such as bombs with Joint Direct Attack Munition (JDAM) guidance and the Small-Diameter Bomb, but cannot self-designate for laser-guided weapons. Internal air-to-surface ordnance is limited to 2,000 lb.An internally mounted M61A2 Vulcan 20 mm cannon is embedded in the right wing root with the muzzle covered by a retractable door to maintain stealth.The radar projection of the cannon fire's path is displayed on the pilot's head-up display.
F22 with AIM 120 in the external pylon |
The F-22's high cruise speed and altitude increase the effective ranges of its munitions, it has 50% greater employment range for the AIM-120 AMRAAM than prior platforms, and range will be further extended with the introduction of the AIM-120D. While specifics are classified, it is expected that JDAMs employed by F-22s will have twice or more the effective range of legacy platforms.[144] In testing, an F-22 dropped a GBU-32 JDAM from 50,000 feet (15,000 m) while cruising at Mach 1.5, striking a moving target 24 miles (39 km) away.
While the F-22 typically carries weapons internally, the wings include four hardpoints, each rated to handle 5,000 lb (2,300 kg). Each hardpoint can accommodate a pylon that can carry a detachable 600 gallon external fuel tank or a launcher holding two air-to-air missiles; the two inboard hardpoints are "plumbed" for external fuel tanks. The use of external stores degrades the aircraft's stealth and kinematic performance; after releasing stores the external attachments can be jettisoned to restore those characteristics. A stealthy ordnance pod and pylon was being developed to carry additional weapons in the mid-2000s.
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