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F22 Design


The Lockheed Martin F-22 Raptor is a single-seat, twin-engine, all weather
stealth tactical fighter aircraft developed for the United States Air Force (USAF).
The result of the USAF's Advanced Tactical Fighter program, the aircraft was
designed primarily as an air superiority fighter, but has additional capabilities
including ground attack, electronic warfare, and signals intelligence roles.[6]
Lockheed Martin is the prime contractor and is responsible for the majority of the
airframe, weapon systems, and final assembly of the F-22, while program partner
Boeing provides the wings, aft fuselage, avionics integration, and training
systems.
The aircraft was variously designated F-22 and FA-22 prior to formally entering
service in December 2005 as the F-22A. Despite a protracted development as well
as operational issues, the USAF considers the F-22 a critical component of its
tactical air power, and states that the aircraft is unmatched by any known or
projected fighter. The Raptor's combination of stealth, aerodynamic performance,
and situational awareness gives the aircraft unprecedented air combat
capabilities.[8] Air Chief Marshal Angus Houston, former Chief of the Australian
Defence Force, said in 2004 that the
plane ever built.
The high cost of the aircraft, a lack of clear air-to-air missions due to delays in

Russian and Chinese fighter programs, a ban on exports, and development of the
more versatile and lower cost F-35 led to the end of F-22 production.[N 1] A final
procurement tally of 187 operational production aircraft was established in 2009
and the last F-22 was delivered to the USAF in 2012.

Overview

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, maneuverability, stealth, and sensor
fusion into a single platform. The Raptor has large shoulder-mounted diamond
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 control surfaces
also serve as the speed brake.
The aircraft's dual afterburning Pratt & Whitney F119-PW-100 turbofan engines
are placed close together and incorporate pitch axis thrust vectoring nozzles
with a range of ±20 degrees; each engine has a 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 sustained

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.[109]
The use of internal weapons bays allows the aircraft to maintain comparatively
higher performance over most other aircraft due to a lack of 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.
The F-22 is highly maneuverable at both supersonic and subsonic speeds.
Computerized fly-by-wire control system and full authority digital engine control
(FADEC) make the aircraft highly departure resistant and enable it to remain
controllable at aggressive pilot inputs. The Raptor's relaxed stability and thrust
vectoring allow 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 F-22 is also capable of maintaining over 60° alpha while having some roll
control.
The F-22's aerodynamic performance, sensor fusion, and stealth work together
for increased effectiveness. Altitude, speed, and advanced active and passive
sensors allow targets to be spotted at considerable ranges and increase
weapons range. Altitude and speed also complement stealth's effectiveness by
increasing distance between the aircraft and ground defenses and giving
defensive systems less time to react.

Avionics

Key avionics include BAE Systems EI&S ANALR-94 radar warning receiver
(RWR),[116] Lockheed Martin ANAAR-56 Infra-Red and Ultra-Violet Missile
Launch Detector (MLD) and Northrop Grumman ANAPG-77 Active Electronically
Scanned Array (AESA) radar. The MLD features six sensors to provide full
spherical infrared coverage.[84] The RWR is a passive radar detector with more
than 30 antennas are blended into the wings and fuselage for all-round coverage.
Tom Burbage, former F-22 program head at Lockheed Martin, described it as
most technically complex piece of equipment on the aircraft.
RWR (250+ nmi) exceeds the radar's, and can cue radar emissions to be confined
to a narrow beam (down to 2° by 2° in azimuth and elevation) to increase stealth.

The ANAPG-77 radar features a low-observable, active-aperture, electronically
scanned array that can track multiple targets under any weather conditions.
Radar emissions can also be focused to overload enemy sensors as an
electronic-attack capability. The radar changes frequencies more than 1,000
times per second to lower interception probability and has an estimated range of
125–150 miles, though planned upgrades will allow a range of 250 miles (400 km)
or more in narrow beams. Radar information is processed by two Raytheon
Common Integrated Processor (CIP)s, each capable of processing up to 10.5
billion instructions per second. In a process known as sensor fusion, data from
the radar, other sensors, and external systems is filtered and combined by the
CIP into a common view, reducing pilot workload.
The F-22's ability to operate close to the battlefield gives the aircraft threat
detection and identification capability comparative with the RC-135 Rivet Joint,
and the ability to function as a
than those of dedicated platforms. The F-22 can designate targets for allies, and
determine whether two friendly aircraft are targeting the same aircraft. This radar
system can sometimes identify targets times quicker than the
AWACS

commercial IEEE-1394
as a wireless data transceiver during tests, transmitting data at 548 megabits per
second and receiving at gigabit speed, far faster than the Link 16 system.
The F-22's software has some 1.7 million lines of code, the majority involving
processing radar data. Former Secretary of the USAF Michael Wynne blamed the
use of the DoD's Ada for cost overruns and delays on many military projects,
including the F-22. Cyberattacks on subcontractors have reportedly raised
doubts about the security of the F-22's systems and combat-effectiveness. In
2009, former Navy Secretary John Lehman considered the F-22 to be safe from
cyberattack, citing the age of its IBM software.
Cockpit

Cockpit of the F-22, showing instruments, head up display and throttle top
The F-22 has a glass cockpit with all-digital flight instruments. The monochrome
head-up display offers a wide field of view and serves as a primary flight
instrument; information is also displayed upon six color liquid crystal display
(LCD) panels. The primary flight controls are a force-sensitive side-stick
controller and a pair of throttles. The USAF initially wanted to implement direct
voice input (DVI) controls, but this was judged to be too technically risky and was
abandoned. The canopy's dimensions are approximately 140 inches long, 45
inches wide, and 27 inches tall (355 cm x 115 cm x 69 cm) and weighs 360
pounds.

The F-22 has integrated radio functionality, the signal processing systems are
virtualized rather than as a separate hardware module. There has been several
reports on the F-22's inability to communicate with other aircraft, and funding
cuts have affected the development of the MADL data link. Voice communication
is possible, but not data transfer.

The integrated control panel (ICP) is a keypad system for entering
communications, navigation, and autopilot data. Two 3 in × 4 in (7.6 cm × 10.2 cm)
up-front displays located around the ICP are used to display integrated caution
advisorywarning data, communications, navigation and identification (CNI) data
and also serve as the stand-by flight instrumentation group and fuel quantity
indicator. The stand- by flight group displays an artificial horizon, for basic
instrument meteorological conditions. The 8 in × 8 in (20 cm × 20 cm) primary
multi-function display (PMFD) is located under the ICP, and is used for navigation
and situation assessment. Three 6.25 in × 6.25 in (15.9 cm × 15.9 cm) secondary
multi- function displays are located around the PMFD for tactical information and
stores management.
The ejection seat is a version of the ACES II (Advanced Concept Ejection Seat)
commonly used in USAF aircraft, with a center-mounted ejection control.[135]
The F-22 has a complex life support system, which includes the on-board oxygen
generation system (OBOGS), protective pilot garments, and a breathing
regulatoranti-g (BRAG) valve controlling flow and pressure to the pilot's mask
and garments. The protective garments are designed to protect against
chemicalbiological hazards and cold-water immersion, to counter g-forces and
low pressure at high altitudes, and to provide thermal relief. It was developed
under the Advanced Technology Anti-G Suit (ATAGS) project.[136] Suspicions
regarding the performance of the OBOGS and life support equipment have been
raised by several mishaps, including a fatal crash.

Armament

AIM-120 AMRAAM (right) fitted in a weapons bay of an F-22
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. It can carry six medium range missiles in the center bay and one
short–range missile in each side bay; Four of the medium range missiles can be
replaced with two bomb racks that can each carry one medium-size or four
smaller 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.[141] Internal air-to-surface ordnance is
limited to 2,000 lb.[142] An internally mounted M61A2 Vulcan 20 mm cannon is
embedded in the right wing root with the muzzle covered by a door to maintain
stealth.[143] The radar projection of the cannon fire's path is displayed on the
pilot's head-up display.

F-22 with external weapons pylons

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 eventual 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.
In testing, an F-22 dropped a 1,000 lb (450 kg) 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 has a pylon
that can carry a detachable 600 gallon fuel tank or a launcher holding two air-air
missiles. The use of external stores degrades the F-22's stealth, maneuverability
and speed. The two inner hardpoints are
hardpoints can be jettisoned in flight to maximize the aircraft's stealth after
exhausting external stores. A stealth ordnance pod and pylon is being developed
to carry additional weapons internally.

Stealth

For stealth, the F-22 carries weapons in internal bays. The doors for the center
and side bays are open; note the six LAU-142A AMRAAM Vertical Ejection
Launchers The F-22 was designed to be highly difficult to detect and track by
radar. Measures to reduce its radar signature include airframe shaping such as
planform alignment of edges, fixed-geometry serpentine inlets that prevent
line-of-sight of the engine faces from any exterior view, use of radar absorbent
material (RAM), and attention to detail such as hinges and pilot helmets that
could provide a radar return. The F-22 was also designed to have decreased
radio, heat and noise emissions as well as reduced visibility to the naked eye.
The aircraft's flat thrust vectoring nozzle reduces infrared emissions to mitigate
the threat of infrared homing (seekingsurface-to-air or air-to-air
missiles.[150] Additional measures to reduce the infrared signature include
special paint and active cooling of leading edges to manage the heat buildup
from supersonic flight.

Compared to previous stealth designs like the F-117, the F-22 is less reliant on
RAM, which are maintenance-intensive and susceptible to adverse weather
conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22
can undergo repairs on the flight line or in a normal hangar. The F-22 features a
Signature Assessment System which delivers warnings when the radar signature
is degraded and necessitates repair.[109] The F-22's exact radar cross-section
(RCS) is classified; however, in 2009 Lockheed Martin released information
indicating it has an RCS (from certain angles) of −40 dBsm – equivalent to the
radar reflection of a marbleEffectively maintaining the stealth
features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS
value is a restrictive measurement of the aircraft's frontal or side area from the
perspective of a static radar. When an aircraft maneuvers it exposes a completely
different set of angles and surface area, potentially increasing radar observability.
Furthermore, the F-22's stealth contouring and radar absorbent materials are
chiefly effective against high-frequency radars, usually found on other aircraft.
The effects of Rayleigh scattering and resonance mean that low- frequency radars,
employed by weather radars and ground warning stations, are more likely to
detect the F-22 due to its physical size. However, such radars are also large,
conspicuous, and less precise. Additionally, while faint or fleeting radar contacts
make defenders aware that a stealth aircraft is present, reliably vectoring

interception to attack the aircraft is much more challenging.[155] According to
the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to
intercept an American UAV, despite Iran's claim of having military VHF radar
coverage over the Persian Gulf.

Specifications (F-22A)
Orthographically projected diagram of the F-22A

F-22 Raptor tail feathers

USAF poster of key F-22 features and armament
Data from USAF, F-22 Raptor Team web site Manufacturers' data
Aviation Week, and Journal of Electronic Defense
General characteristics

Crew: 1
Length: 62 ft 1 in (18.92 m)
Wingspan: 44 ft 6 in (13.56 m)
Height: 16 ft 8 in (5.08 m)
Wing area: 840 ft² (78.04 m²)
Airfoil: NACA 64A?05.92 root, NACA 64A?04.29 tip
Empty weight: 43,340 lb (19,700 kg)
Loaded weight: 64,840 lb (29,410 kg)
Max. takeoff weight: 83,500 lb (38,000 kg)
Powerplant: 2 × Pratt & Whitney F119-PW-100 pitch thrust vectoring turbofans
Dry thrust: 26,000 lb (116 kN) each
Thrust with afterburner: 35,000+ lb (156+ kN) each
Fuel capacity: 18,000 lb (8,200 kg) internally, or 26,000 lb (12,000 kg) with two
external fuel tanks
Performance

Maximum speed:
At altitude: Mach 2.25 (1,500 mph, 2,410 kmh)
Supercruise: Mach 1.82 (1,220 mph, 1,960 kmh)
Range: >1,600 nmi (1,840 mi, 2,960 km) with 2 external fuel tanks
Combat radius: 410 nmi (with 100 nmi in supercruise) (470 mi, 760 km)

Ferry range: 2,000 mi (1,740 nmi, 3,220 km)
Service ceiling: >65,000 ft (20,000 m)
Wing loading: 77.2 lbft² (377 kgm²)
Thrustweight: 1.08
Maximum design g-load: −3.0+9.0 g
Armament

Guns: 1× 20 mm (0.787 in) M61A2 Vulcan 6-barrel Gatling cannon in right wing
root, 480 rounds
Air to air loadout:
6× AIM-120 AMRAAM
2× AIM-9 Sidewinder
Air to ground loadout:
2× 1,000 lb (450 kg) JDAM or 8× 250 lb (110 kg) GBU-39 Small Diameter Bombs
2× AIM-120 AMRAAM
2× AIM-9 Sidewinder
Hardpoints: 4× under-wing pylon stations can be fitted to carry 600 U.S. gallon
drop tanks or weapons, each with a capacity of 5,000 lb (2,270 kg).
Avionics

ANAPG-77 radar: 125–150 miles (200–240 km) against 1 m2 (11 sq ft) targets
(estimated range)
ANAAR-56 Missile Launch Detector (MLD)
ANALR-94 radar warning receiver (RWR): 250 nmi (463 km) or more detection
range
MJU-3940 flares for protection against IR missiles

F22 Design


The Lockheed Martin F-22 Raptor is a single-seat, twin-engine, all weather
stealth tactical fighter aircraft developed for the United States Air Force (USAF).
The result of the USAF's Advanced Tactical Fighter program, the aircraft was
designed primarily as an air superiority fighter, but has additional capabilities
including ground attack, electronic warfare, and signals intelligence roles.[6]
Lockheed Martin is the prime contractor and is responsible for the majority of the
airframe, weapon systems, and final assembly of the F-22, while program partner
Boeing provides the wings, aft fuselage, avionics integration, and training
systems.
The aircraft was variously designated F-22 and FA-22 prior to formally entering
service in December 2005 as the F-22A. Despite a protracted development as well
as operational issues, the USAF considers the F-22 a critical component of its
tactical air power, and states that the aircraft is unmatched by any known or
projected fighter. The Raptor's combination of stealth, aerodynamic performance,
and situational awareness gives the aircraft unprecedented air combat
capabilities.[8] Air Chief Marshal Angus Houston, former Chief of the Australian
Defence Force, said in 2004 that the
plane ever built.
The high cost of the aircraft, a lack of clear air-to-air missions due to delays in

Russian and Chinese fighter programs, a ban on exports, and development of the
more versatile and lower cost F-35 led to the end of F-22 production.[N 1] A final
procurement tally of 187 operational production aircraft was established in 2009
and the last F-22 was delivered to the USAF in 2012.

Overview

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, maneuverability, stealth, and sensor
fusion into a single platform. The Raptor has large shoulder-mounted diamond
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 control surfaces
also serve as the speed brake.
The aircraft's dual afterburning Pratt & Whitney F119-PW-100 turbofan engines
are placed close together and incorporate pitch axis thrust vectoring nozzles
with a range of ±20 degrees; each engine has a 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 sustained

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.[109]
The use of internal weapons bays allows the aircraft to maintain comparatively
higher performance over most other aircraft due to a lack of 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.
The F-22 is highly maneuverable at both supersonic and subsonic speeds.
Computerized fly-by-wire control system and full authority digital engine control
(FADEC) make the aircraft highly departure resistant and enable it to remain
controllable at aggressive pilot inputs. The Raptor's relaxed stability and thrust
vectoring allow 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 F-22 is also capable of maintaining over 60° alpha while having some roll
control.
The F-22's aerodynamic performance, sensor fusion, and stealth work together
for increased effectiveness. Altitude, speed, and advanced active and passive
sensors allow targets to be spotted at considerable ranges and increase
weapons range. Altitude and speed also complement stealth's effectiveness by
increasing distance between the aircraft and ground defenses and giving
defensive systems less time to react.

Avionics

Key avionics include BAE Systems EI&S ANALR-94 radar warning receiver
(RWR),[116] Lockheed Martin ANAAR-56 Infra-Red and Ultra-Violet Missile
Launch Detector (MLD) and Northrop Grumman ANAPG-77 Active Electronically
Scanned Array (AESA) radar. The MLD features six sensors to provide full
spherical infrared coverage.[84] The RWR is a passive radar detector with more
than 30 antennas are blended into the wings and fuselage for all-round coverage.
Tom Burbage, former F-22 program head at Lockheed Martin, described it as
most technically complex piece of equipment on the aircraft.
RWR (250+ nmi) exceeds the radar's, and can cue radar emissions to be confined
to a narrow beam (down to 2° by 2° in azimuth and elevation) to increase stealth.

The ANAPG-77 radar features a low-observable, active-aperture, electronically
scanned array that can track multiple targets under any weather conditions.
Radar emissions can also be focused to overload enemy sensors as an
electronic-attack capability. The radar changes frequencies more than 1,000
times per second to lower interception probability and has an estimated range of
125–150 miles, though planned upgrades will allow a range of 250 miles (400 km)
or more in narrow beams. Radar information is processed by two Raytheon
Common Integrated Processor (CIP)s, each capable of processing up to 10.5
billion instructions per second. In a process known as sensor fusion, data from
the radar, other sensors, and external systems is filtered and combined by the
CIP into a common view, reducing pilot workload.
The F-22's ability to operate close to the battlefield gives the aircraft threat
detection and identification capability comparative with the RC-135 Rivet Joint,
and the ability to function as a
than those of dedicated platforms. The F-22 can designate targets for allies, and
determine whether two friendly aircraft are targeting the same aircraft. This radar
system can sometimes identify targets times quicker than the
AWACS

commercial IEEE-1394
as a wireless data transceiver during tests, transmitting data at 548 megabits per
second and receiving at gigabit speed, far faster than the Link 16 system.
The F-22's software has some 1.7 million lines of code, the majority involving
processing radar data. Former Secretary of the USAF Michael Wynne blamed the
use of the DoD's Ada for cost overruns and delays on many military projects,
including the F-22. Cyberattacks on subcontractors have reportedly raised
doubts about the security of the F-22's systems and combat-effectiveness. In
2009, former Navy Secretary John Lehman considered the F-22 to be safe from
cyberattack, citing the age of its IBM software.
Cockpit

Cockpit of the F-22, showing instruments, head up display and throttle top
The F-22 has a glass cockpit with all-digital flight instruments. The monochrome
head-up display offers a wide field of view and serves as a primary flight
instrument; information is also displayed upon six color liquid crystal display
(LCD) panels. The primary flight controls are a force-sensitive side-stick
controller and a pair of throttles. The USAF initially wanted to implement direct
voice input (DVI) controls, but this was judged to be too technically risky and was
abandoned. The canopy's dimensions are approximately 140 inches long, 45
inches wide, and 27 inches tall (355 cm x 115 cm x 69 cm) and weighs 360
pounds.

The F-22 has integrated radio functionality, the signal processing systems are
virtualized rather than as a separate hardware module. There has been several
reports on the F-22's inability to communicate with other aircraft, and funding
cuts have affected the development of the MADL data link. Voice communication
is possible, but not data transfer.

The integrated control panel (ICP) is a keypad system for entering
communications, navigation, and autopilot data. Two 3 in × 4 in (7.6 cm × 10.2 cm)
up-front displays located around the ICP are used to display integrated caution
advisorywarning data, communications, navigation and identification (CNI) data
and also serve as the stand-by flight instrumentation group and fuel quantity
indicator. The stand- by flight group displays an artificial horizon, for basic
instrument meteorological conditions. The 8 in × 8 in (20 cm × 20 cm) primary
multi-function display (PMFD) is located under the ICP, and is used for navigation
and situation assessment. Three 6.25 in × 6.25 in (15.9 cm × 15.9 cm) secondary
multi- function displays are located around the PMFD for tactical information and
stores management.
The ejection seat is a version of the ACES II (Advanced Concept Ejection Seat)
commonly used in USAF aircraft, with a center-mounted ejection control.[135]
The F-22 has a complex life support system, which includes the on-board oxygen
generation system (OBOGS), protective pilot garments, and a breathing
regulatoranti-g (BRAG) valve controlling flow and pressure to the pilot's mask
and garments. The protective garments are designed to protect against
chemicalbiological hazards and cold-water immersion, to counter g-forces and
low pressure at high altitudes, and to provide thermal relief. It was developed
under the Advanced Technology Anti-G Suit (ATAGS) project.[136] Suspicions
regarding the performance of the OBOGS and life support equipment have been
raised by several mishaps, including a fatal crash.

Armament

AIM-120 AMRAAM (right) fitted in a weapons bay of an F-22
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. It can carry six medium range missiles in the center bay and one
short–range missile in each side bay; Four of the medium range missiles can be
replaced with two bomb racks that can each carry one medium-size or four
smaller 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.[141] Internal air-to-surface ordnance is
limited to 2,000 lb.[142] An internally mounted M61A2 Vulcan 20 mm cannon is
embedded in the right wing root with the muzzle covered by a door to maintain
stealth.[143] The radar projection of the cannon fire's path is displayed on the
pilot's head-up display.

F-22 with external weapons pylons

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 eventual 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.
In testing, an F-22 dropped a 1,000 lb (450 kg) 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 has a pylon
that can carry a detachable 600 gallon fuel tank or a launcher holding two air-air
missiles. The use of external stores degrades the F-22's stealth, maneuverability
and speed. The two inner hardpoints are
hardpoints can be jettisoned in flight to maximize the aircraft's stealth after
exhausting external stores. A stealth ordnance pod and pylon is being developed
to carry additional weapons internally.

Stealth

For stealth, the F-22 carries weapons in internal bays. The doors for the center
and side bays are open; note the six LAU-142A AMRAAM Vertical Ejection
Launchers The F-22 was designed to be highly difficult to detect and track by
radar. Measures to reduce its radar signature include airframe shaping such as
planform alignment of edges, fixed-geometry serpentine inlets that prevent
line-of-sight of the engine faces from any exterior view, use of radar absorbent
material (RAM), and attention to detail such as hinges and pilot helmets that
could provide a radar return. The F-22 was also designed to have decreased
radio, heat and noise emissions as well as reduced visibility to the naked eye.
The aircraft's flat thrust vectoring nozzle reduces infrared emissions to mitigate
the threat of infrared homing (seekingsurface-to-air or air-to-air
missiles.[150] Additional measures to reduce the infrared signature include
special paint and active cooling of leading edges to manage the heat buildup
from supersonic flight.

Compared to previous stealth designs like the F-117, the F-22 is less reliant on
RAM, which are maintenance-intensive and susceptible to adverse weather
conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22
can undergo repairs on the flight line or in a normal hangar. The F-22 features a
Signature Assessment System which delivers warnings when the radar signature
is degraded and necessitates repair.[109] The F-22's exact radar cross-section
(RCS) is classified; however, in 2009 Lockheed Martin released information
indicating it has an RCS (from certain angles) of −40 dBsm – equivalent to the
radar reflection of a marbleEffectively maintaining the stealth
features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS
value is a restrictive measurement of the aircraft's frontal or side area from the
perspective of a static radar. When an aircraft maneuvers it exposes a completely
different set of angles and surface area, potentially increasing radar observability.
Furthermore, the F-22's stealth contouring and radar absorbent materials are
chiefly effective against high-frequency radars, usually found on other aircraft.
The effects of Rayleigh scattering and resonance mean that low- frequency radars,
employed by weather radars and ground warning stations, are more likely to
detect the F-22 due to its physical size. However, such radars are also large,
conspicuous, and less precise. Additionally, while faint or fleeting radar contacts
make defenders aware that a stealth aircraft is present, reliably vectoring

interception to attack the aircraft is much more challenging.[155] According to
the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to
intercept an American UAV, despite Iran's claim of having military VHF radar
coverage over the Persian Gulf.

Specifications (F-22A)
Orthographically projected diagram of the F-22A

F-22 Raptor tail feathers

USAF poster of key F-22 features and armament
Data from USAF, F-22 Raptor Team web site Manufacturers' data
Aviation Week, and Journal of Electronic Defense
General characteristics

Crew: 1
Length: 62 ft 1 in (18.92 m)
Wingspan: 44 ft 6 in (13.56 m)
Height: 16 ft 8 in (5.08 m)
Wing area: 840 ft² (78.04 m²)
Airfoil: NACA 64A?05.92 root, NACA 64A?04.29 tip
Empty weight: 43,340 lb (19,700 kg)
Loaded weight: 64,840 lb (29,410 kg)
Max. takeoff weight: 83,500 lb (38,000 kg)
Powerplant: 2 × Pratt & Whitney F119-PW-100 pitch thrust vectoring turbofans
Dry thrust: 26,000 lb (116 kN) each
Thrust with afterburner: 35,000+ lb (156+ kN) each
Fuel capacity: 18,000 lb (8,200 kg) internally, or 26,000 lb (12,000 kg) with two
external fuel tanks
Performance

Maximum speed:
At altitude: Mach 2.25 (1,500 mph, 2,410 kmh)
Supercruise: Mach 1.82 (1,220 mph, 1,960 kmh)
Range: >1,600 nmi (1,840 mi, 2,960 km) with 2 external fuel tanks
Combat radius: 410 nmi (with 100 nmi in supercruise) (470 mi, 760 km)

Ferry range: 2,000 mi (1,740 nmi, 3,220 km)
Service ceiling: >65,000 ft (20,000 m)
Wing loading: 77.2 lbft² (377 kgm²)
Thrustweight: 1.08
Maximum design g-load: −3.0+9.0 g
Armament

Guns: 1× 20 mm (0.787 in) M61A2 Vulcan 6-barrel Gatling cannon in right wing
root, 480 rounds
Air to air loadout:
6× AIM-120 AMRAAM
2× AIM-9 Sidewinder
Air to ground loadout:
2× 1,000 lb (450 kg) JDAM or 8× 250 lb (110 kg) GBU-39 Small Diameter Bombs
2× AIM-120 AMRAAM
2× AIM-9 Sidewinder
Hardpoints: 4× under-wing pylon stations can be fitted to carry 600 U.S. gallon
drop tanks or weapons, each with a capacity of 5,000 lb (2,270 kg).
Avionics

ANAPG-77 radar: 125–150 miles (200–240 km) against 1 m2 (11 sq ft) targets
(estimated range)
ANAAR-56 Missile Launch Detector (MLD)
ANALR-94 radar warning receiver (RWR): 250 nmi (463 km) or more detection
range
MJU-3940 flares for protection against IR missiles

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