The Northrop F-20 Tigershark (initially F-5G) was a privately financed light fighter, designed and built by Northrop. Its development began in 1975 as a further evolution of Northrop’s F-5E Tiger II, featuring a new engine that greatly improved overall performance, and a modern avionics suite including a powerful and flexible radar. Compared with the F-5E, the F-20 was much faster, gained beyond-visual-range air-to-air capability, and had a full suite of air-to-ground modes capable of firing most U.S. weapons. With these improved capabilities, the F-20 became competitive with contemporary fighter designs such as the General Dynamics F-16 Fighting Falcon, but was much less expensive to purchase and operate.
Much of the F-20’s development was carried out under a US Department of Defense (DoD) project called “FX”. FX sought to develop fighters that would be capable in combat with the latest Soviet aircraft, but excluding sensitive front-line technologies used by the United States Air Force’s own aircraft. FX was a product of the Carter administration’s military export policies, which aimed to provide foreign nations with high quality equipment without the risk of US front-line technology falling into Soviet hands. Northrop had high hopes for the F-20 in the international market, but policy changes following Ronald Reagan’s election meant the F-20 had to compete for sales against aircraft like the F-16, the USAF’s latest fighter design. The development program was abandoned in 1986 after three prototypes had been built and a fourth partially completed.
“F-20 Tigershark The Greatest Fighter Never Made” Here
“From an armchair generals perspective there is no reason this shouldn’t be in service all around their globe. Why a small air force would need something as complex as the F-16 seems absurd. Add in the fact that the F-5 was used as the aggressor aircraft for the US aircraft to train its front line fighters how to dogfight and it gets even more confusing. Until the F-22 and F-35 came along there was nothing that could out maneuver a F-5 or F-20. This was a future that was never meant to be.” Source – “F-20 Tigershark The Greatest Fighter Never Made” posted By Fodder, on May 24th, 2012 (Link above)
The primary design change between the earlier F-5E and the F-5G was the use of a single General Electric F404 engine that was originally designed for the F/A-18 Hornet. The new engine provided 60% more thrust compared to the combined output of the F-5E’s paired General Electric J85s. This improved the aircraft’s thrust-to-weight ratio to 1.13 from 1.0. The new engine gave speed of over Mach 2.0, a ceiling over 55,000 ft (16,800 m), an initial climb rate of 52,800 ft per minute (16,100m/min).
General Electric F404 engine
F404, augmented turbofan with low bypass ratio, was developed in min 70’s on the base of J101-GE-100’s core. Performance and reliability of F404 made a new standard for modern jet engines of wide range of military jets – starting with low-altitude strike planes and ending with hi-altitude interceptors. War proved engines accumulated more than 8 millon flight hours in service of US Navy, US Marine Corps, USAF and airforces of Australia, Canada, Finland, Kuwait, Malaysia, Singapore, Spain, Sweden, Switzerland and others.
- 3-stage fan with variable vanes of first stator
- 7-stage compressor with variable inlet guide vanes and vanes of first and second stator stage, airbleed is up to 7,25%
- annular combustion chamber
- 1-stage high-pressure turbine (air cooled)
- 1-stage low-pressure turbine (air cooled)
- afterburner chamber
- convergent-divergent exhaust nozzle
- control system: hydromechanical, electronical
- lubrication system uses MIL-L-5624 or MIL-L-7808 oil, consumption is 0,4 liters per hour
F404 uses standard MIL-5624, JP-4, JP-5 or JP-8 fuel.
The first engine of F404 family, the F404-GE-400, was originaly proposed for naval F/A-18, and became one of the best and most widespread engines of that era. Modern materials, simplified diagnostics, well positioned access points and modular construction ensures high lifetime and low operation cost. Modular construction with six modules simplifies replacement of damaged parts and shortens maintenance time (e.g. on aircraft carrier). Visual inspection of interior parts can be accomplished via 13 entry points. The engine needs no special test and fine-tuning after reparation of it’s core. Naval usage required corrosion proof components.
Pilots appreciate a free thrust handling, fast RPM response on acceleration or deceleration and smooth maximal thrust to afterburner transition. Engine is in service since 1981, production name is LM1600. Beside the F/A-18 of A, B, C and D version, the engine was used also on F-5G, experimental X-29 and X-31A. It’s said that the F404 was one of the possibilities to power the French Rafale. Unaugmented variant of -400 was one of the competitior for upgrade of A-6E planes.
F404-GE-402EPE (Enhanced Performance Engine)
This variant has higher thrust and lower specific fuel consumption, which were archived by using the newest technologies and materials when designing the turbine and afterburner section. Of course with no negative influence on lifetime of this parts. Engine is being installed to F/A-18C/D since October 1982 and improves combat capabilities of this aircraft.
Probably based on -400 and intended for F-5G (F-20A) fighters.
Derivate of -400 without afterburner. Singapore with cooperation with GE replaced J65 engines of their A-4 Skyhawk motory J65 for F404-GE-100Ds and so made gave born to a new A-4S Super Skyhawk version. New engine gives the plane a higher airspeed, better acceleration and maneuverability and lowers the fuel burn. F404-GE-100D is for it’s single-engine usage equipped with extra safety features to prevent malfunctions during the flight.
F1D2 is unaugmented derivate of basic -400, is used by two-engine stealth planes F-117A. The interesting thing is exhaust gas cooler which comprises of a flat nozzle 20 cm high and 165 cm wide.
Used to power prototyped of indian light combat plane LCA. Production planes will have indian engines GTRE GTX-35VS Kaveri
Next developement stage of F404, this time based on -402. Engine was developed by GE and KAI (Korean Aerospace Industries). The engine has safety features (for single-engine use) and FADEC. It should power light combat plane T-50 / A-50 developed in cooperation of KAI and LM (Lockheed Martin). Engine ought to be first tested in 2001, first flight of new plane were to be conducted in 2002 and production of engine had to start in 2005.
The RM12 engine was developed by GE Aircraft Engines and Volvo Aero Corporation to power Swedish JAS-39 Gripen fighter. RM12, specially designed for single-engine use has a few different characteristic compared to it’ father F404-GE-400. First of all the fan has been strengthen to sustain a hit of 0.5 kg bird, the airflow was highten by 10% and the turbine was made of modern materials to stand higher temperatures. All of this increased the overall performance by 10-20%. Engine has FADEC with hydromachanical backup and backup ignition system. The RM12 has fast power setting response, unlimited number of power cycles, smooth to-afterburner transition and is very reliable. .
|Fan pressure ratio||x||3,9|
|Overall pressure ratio||x||25||26||25||25||26||27|
|Temperature – max turbine inlet||°C||1348||1444|
|– max turbine outlet||°C||797||869|
|Thrust – maximal (SLS)||kp||4990||4763||4808||5420||5507|
|– with afterburner (SLS)||kp||7711||není||8030||není||7257||8030||8210|
|SFC – maximal thrust (SLS)||kg/kN/h||81,6||82,6||87,0||84,0|
|– afterburner (SLS)||kg/kN/h||188,6||177,4||181,5|
Engine data @leteckemotory.cz
The wing profile remained the same as the F-5E, but had modified leading edge extensions (LEX), which improved the maximum lift coefficient of the wing by about 12% with an increase in wing area of only 1.6%. The original aircraft was fairly sluggish in pitch, so the horizontal stabilizer was increased in size by 30% and a new dual-channel fly-by-wire control system was added. Destabilizing the aircraft in pitch and modifying the LEX improved the instantaneous turn rate by 7% to 20°/sec. Sustained turn rate at Mach 0.8 and 15,000 ft (4,572 m) rose to 11.5°/sec, which compared well with the F-16’s 12.8°/sec. Supersonic turn rates were 47% higher than those of the F-5E.
F-20 Leading edge extensions (LEX)
The F-20 would also make greater usage of composite materials in its construction. During its development, several areas using metal were re-designed to use fiberglass, and there were numerous upgrades to various mechanical parts.
The F-20’s avionics suite was all-new and greatly improved over the earlier designs. The General Electric AN/APG-67 multi-mode radar was the heart of the sensor suite, offering a wide range of air-to-air and air-to-ground modes.
AN/APG-67 multi-mode radar
The F-20A avionics system incorporated the highly reliable General Electric AN/APG-67(V) radar, designed for a 200 hour MTBF. It was an X – band, pulse – doppler, digital, multimode radar, using low pulse repetition frequency (PRF) in the look up mode, medium PRF in the look down mode, and high PRF for velocity search.
The detection range of the AN/APG-67(V) permitted the F-20A to detect most adversary aircraft before the F-20A, with its low radar cross section, was detected by the adversary.
- Modular design
- X band coherent pulse doppler
- Digital, multimode
- Low, medium. and high PRF
- AIR TO AIR
- Look up, look down range while search
- Velocity search
- Single target track
- Air combat modes with automatic acquisition
- Track while scan*
- AIR TO SURFACE
- Ground map/doppler beam sharpened map
- Display freeze mode
- Moving target indication*
- Moving target track*
- Beacon track (option)*
- AIR TO SEA
- Sea surface search (SEA 1)
- Sea moving target indication (SEA 2)*
- Sea moving target track*
- AIR TO AIR
- Range: 80 nmi (maximum displayed)
- Angular coverage: 160 degree cone
- Map resolution: 45 feet at 5.0 nmi
- Beamwidth: 3.7 degrees azimuth, 5.4 degrees elevation
- Air to ground range accuracy: 50 feet or 0.5 percent of range
- Air target detection (fighter size target) –Look up–47 nmi –Look down–38 nmi
- Sea target detection (patrol boat size target) –Sea 1–47 nmi –Sea 2–40 nmi
- Antenna: 16.7 by 26.2 inches
- Power: 2340 VA
- Weight: 270 pounds
- Volume: 3.1 cubic feet
- Reliability: 200 hours MTBF
AN/APG-67(V) radar data @thecid.com
The F-5’s electro-mechanical navigation system was replaced with an all-electronic version based on a ring laser gyroscope. Time from power-on to being able to launch was greatly reduced as a result, to about 22 seconds, and Northrop boasted the aircraft had the shortest scramble time of any contemporary aircraft. The cockpit of the F-5 was completely re-worked with a large heads-up display (HUD) and two monochrome multi-function displays set high on the control panel, and the addition of a complete hands-on-throttle-and-stick (HOTAS) control system. Many of the avionics promised to have reliability beyond that of any competing aircraft then in service.
The F-20 would have been able to utilize most of the common weapons in U.S.’s inventory, including the entire range of Mark 80 series bombs, the AGM-65 Maverick air-to-ground missile, and the AIM-9 Sidewinder and AIM-7 Sparrow air-to-air missiles. Like the earlier F-5s, the test F-20s were equipped with two M39 cannon mounted in the nose. Production F-20s may have substituted two Ford Aerospace Tigerclaw cannons instead of the M39s; while the Tigerclaw was based on the M39, it was lighter and had a higher rate of fire than the M39A2.
Manufactured by Pontiac Motors Division of General Motors, Pontiac, Mi. – The M39A2 is a gas-operated, revolver-type, air-cooled automatic gun which fires electric primed ammunition from a metallic linked-belt.
Ammunition may be fed into the gun from either the left or right side. Weapon is distinguished by a 5-chamber drum which revolves about an axis, parallel to the gun bore.
M39A3 and M39A2(Feeder assembly)
M39A3 and M39A2(Feeder assembly) – The feeder assembly makes it possible for connected bullets to get out of the feeder road run to the drum and separates the link to enable it to move into the Road of Discharge. It also makes it possible for an empty cartridge to be driven out of the Cartridge Chamber and removed through a burned shot, and it follows thelinear motion of the gunshot and makes itself ready for the next shot. Source @kdia.or.kr
Weapon fires the 20-mm cartridge at the index drum position of the 6 o’clock chamber. 9-groove rifling; right-hand gain twist. Muzzle velocity with API and HEI ammunition is 8300 fps. Cyclic rate of fire approximately 750 rpm. Maximum range is 5,750 yards. Weapon has an overall length of 72 1/4″, a barrel length of 53 1/2″ and weighs approximately 179 lbs.
The AIM-9 has a cylindrical body with a roll-stabilizing rear wing/rolleron assembly. Also, it has detachable, double-delta control surfaces behind the nose that improve the missile’s maneuverability. Both rollerons and control surfaces are in a cross-like arrangement.
The missile’s main components are an infrared homing guidance section, an active optical target detector, a high-explosive warhead, and a rocket motor.
The infrared guidance head enables the missile to home on target aircraft engine exhaust. An infrared unit costs less than other types of guidance systems, and can be used in day/night and electronic countermeasures conditions. The infrared seeker also permits the pilot to launch the missile, then leave the area or take evasive action while the missile guides itself to the target.
|Primary Function||Air-to-air missile|
|Contractor||Naval Weapons Center|
|Power Plant||Hercules and Bermite Mk 36 Mod 71, 8 solid-propellant rocket motor|
|Speed||Supersonic Mach 2.5|
|Range||10 to 18 miles depending on altitude|
|Length||9 feet, 5 inches (2.87 meters)|
|Diameter||5 inches (0.13 meters)|
|Finspan||2 feet, 3/4 inches (0.63 meters)|
|Warhead||Annular blast fragmentation warhead
25 lbs high explosive for AIM-9H
20.8 lbs high explosive for AIM-9L/M
|Launch Weight||190 pounds (85.5 kilograms)|
|Guidance System||Solid-state, infrared homing system|
AIM-9 data @fas.org
The AIM-7 Sparrow is a radar-guided, air-to-air missile with a high-explosive warhead. The versatile Sparrow has all-weather, all-altitude operational capability and can attack high-performance aircraft and missiles from any direction. The AIM/RIM-7 series is a semiactive, air-to-air, boost-glide missile, designed to be either rail or ejection launched. Semiactive, continuous wave, homing radar, and hydraulically-operated control surfaces direct and stabilize the missile on a proportional navigational course to the target. Propulsion for the missile is provided by a solid propellant rocket motor.
The Sparrow missile is a supersonic, medium-range, aerial-intercept missile that guides on Radio Frequency (RF) energy. Sparrow incorporates Electronic Counter-Countermeasure (ECCM) capabilities, also known as Electronic Protection (EP), to defeat countermeasures such as jamming. The Sparrow began as project Hotshot in 1946, and became operational in late 1953. Experience during the Vietnam war demonstrated it to be virtually useless against manuvering targets. A special AIM-7E-2 dogfight version was produced to overcome these shortcomings. Current configurations of the Sparrow missile include four air-launched variants, AIM-7M F1 Build, AIM-7M H Build, AIM-7P Block I, and AIM-7P Block II, and as many ship-launched variants, RIM-7M F1 Build, RIM-7M H Build, RIM-7P Block I, and RIM-7P Block II.
Each new version has resulted in substantial improvement in missile performance. The AIM/RIM-7E reduced minimum range restrictions and provided dogfight capabilities. The RIM-7H incorporates rapid run-up capabilities, providing improvements over previous versions. The AIM-7F incorporates solid state circuitry and modular design, an improved warhead, and a boost-sustain rocket motor. The AIM/RIM-7R is most recent configuration and adds a dual mode radio frequency/infrared (RF/IR) seeker capability.
|Primary Function||Air-to-air guided missile|
|Power Plant||Hercules MK-58 solid-propellant rocket motor|
|Range||approximately 30 nm|
|Length||12 feet (3.64 meters)|
|Diameter||8 inches (0.20 meters)|
|Wingspan||3 feet, 4 inches (1 meter)|
|Warhead||Annular blast fragmentation warhead
88 lbs high explosive for AIM-9H
|Launch Weight||Approximately 500 pounds (225 kilograms)|
|Guidance System||Raytheon semiactive on either continuous wave or pulsed Doppler radar energy|
|Aircraft Platforms||Navy: F-14 and F/A-18;
Air Force: F-4, F-15, and F-16;
Marine Corps: F-4 and F/A-18
AIM-7 Sparrow data @fas.org
The AGM-65 Maverick is a tactical, air-to-surface guided missile designed for close air support, interdiction and defense suppression mission. It provides stand-off capability and high probability of strike against a wide range of tactical targets, including armor, air defenses, ships, transportation equipment and fuel storage facilities. Maverick was used during Operation Desert Storm and, according to the Air Force, hit 85 percent of its targets.
The Maverick has a cylindrical body, and either a rounded glass nose for electro-optical imaging, or a zinc sulfide nose for imaging infrared. It has long-chord delta wings and tail control surfaces mounted close to the trailing edge of the wing of the aircraft using it. The warhead is in the missile’s center section. A cone-shaped warhead, one of two types carried by the Maverick missile, is fired by a contact fuse in the nose. The other is a delayed-fuse penetrator, a heavyweight warhead that penetrates the target with its kinetic energy before firing. The latter is very effective against large, hard targets. The propulsion system for both types is a solid-rocket motor behind the warhead.
The Maverick variants include electro-optical/television (A and B), imaging infrared (D, F, and G), or laser guidance (E). The Air Force developed the Maverick, and the Navy procured the imaging infrared and the laser guided versions. The AGM-65 has two types of warheads, one with a contact fuse in the nose, the other a heavyweight warhead with a delayed fuse, which penetrates the target with its kinetic energy before firing. The latter is very effective against large, hard targets. The propulsion system for both types is a solid-rocket motor behind the warhead.
|Primary Function:||Air-to-surface guided missile|
|Contractors:||Hughes Aircraft Co., Raytheon Co.|
|Power Plant:||Thiokol TX-481 solid-propellant rocket motor|
|Service||Air Force||Marine Corps||Navy|
|Launch Weight:||462 lbs
|Diameter:||1 foot (30.48 centimeters)|
|Wingspan:||2 feet, 4 inches (71.12 centimeters)|
|Range:||17+ miles (12 nautical miles/27 km)|
|Guidance System:||electro-optical television||imaging infrared||Laser||infrared homing|
delayed-fuse penetrator, heavyweight
delayed-fuse penetrator, heavyweight
|Explosive||86 lbs. Comp B||80 lbs. PBX(AF)-108|
|Date Deployed:||August 1972||February 1986||1989|
|Aircraft:||A-10, F-15E and F-16||F/A-18||F/A-18 and AV-8B|
AGM-65 Maverick data @fas.org
The F-20 did, however, have several problems inherent to its small size. The low-mounted wing meant that there was limited ground clearance, and the position of the landing gear meant loads had to be positioned towards the outer ends of the wings. This limited hard point weights to 1,000 lb (454 kg). A single hard point under the fuselage could carry more, a single Mk 84 2,000 lbs bomb or up to five Mk 82 500 lbs bombs. Additionally, although the wing profiling improved lift at higher angles of attack (AoA) while maneuvering, it did not improve cruise lift performance at normal AoA. This did not present a problem in the fighter role, but did severely reduce its payload/range figures compared to similar aircraft like the F-16.
Mk 82 500 lbs bombs
Matra rocket pods with 18 × SNEB 68 mm rockets each
Matra Type 155 rocket launcher — Widely produced, this was a reusable device manufactured completely from metal with a fluted nose cone through which the RPs were fired. Loaded with 18 SNEB 68mm rockets, it can be pre-programmed on the ground to fire in shots or in one single ripple salvo as the Type 116M.
SNEB rocket projectile
The caliber of 68 mm was preferred by the French over other international designs of 57 mm, 70 mm, or 80 mm. The SNEB rocket projectile is propelled by a single rocket motor, and, depending on the warhead loadout on the launchers, it can be used against armoured fighting vehicles, bunkers, or soft targets.
CBU-24/49/52/58 cluster bomb munitions
Offered as a low-cost option, the F-20 was significantly more expensive than the F-5E, but much less expensive than other designs like the $30 million F-15 Eagle, or $15 million F-16 Fighting Falcon. The F-20 was projected to consume 53% less fuel, require 52% less maintenance manpower, had 63% lower operating and maintenance costs and had four times the reliability of average front-line designs of the era. The F-20 also offer the ability to fire the beyond-visual-range AIM-7 Sparrow missile, a capability that the F-16 lacked at that time, and did not gain until the Block 15 ADF version in February 1989.
General characteristicsData from Northrop F-5/F-20/T-38, Complete Encyclopedia of World Aircraft
- Crew: 1 pilot
- Length: 47 ft 4 in (14.4 m)
- Wingspan: 27 ft 11.9 in / 8.53 m; with wingtip missiles (26 ft 8 in/ 8.13 m; without wingtip missiles)
- Height: 13 ft 10 in (4.20 m)
- Wing area: 200 ft² (18.6 m²)
- Empty weight: 13,150 lb (5,964 kg)
- Loaded weight: 15,480 lb (7,021 kg)
- Max. takeoff weight: 27,500 lb (12,474 kg)
- Powerplant: 1 × General Electric F404-GE-100 turbofan, 17,000 lbf (76 kN)
- Maximum speed: Mach 2 (1,319 miles, 2,123 km per hour)
- Combat radius: 300 nmi (345 mi, 556 km) ; for hi-lo-hi mission with 2 × 330 US gal (1,250 L) drop tanks
- Ferry range: 1,490 nmi (1715 mi, 2759 km) ; with 3 × 330 US gal (1,250 L) drop tanks
- Service ceiling: 55,000 ft (16,800 m)
- Rate of climb: 52,800 ft/min (255 m/s)
- Wing loading: 81.0 lb/ft² (395 kg/m²)
- Thrust/weight: 1.1
- Guns: 2× 20 mm (0.79 in) Pontiac M39A2 cannons in the nose, 280 rounds each
- Hardpoints: 5 external hardpoints with a capacity of 8,000 lb (3,600 kg) of bombs, missiles, rockets and up to 3 drop tanks for extended range
- Rockets: 2 × CRV7 rocket pods Or
2 × LAU-10 rocket pods with 4 × Zuni 5 in (127 mm) rockets each Or
2 × Matra rocket pods with 18 × SNEB 68 mm rockets each
- Missiles: 2 × AIM-9 Sidewinders on wingtip launch rails (similar to F-16 and F/A-18)
Up to 4 x AIM-7 Sparrows on underwing launch rails
AGM-65 Maverick air-to-surface missiles on hardpoints
- Bombs: Various air-to-ground ordnance such as Mark 80 series of unguided iron bombs (including 3 kg and 14 kg practice bombs), CBU-24/49/52/58 cluster bomb munitions, M129 Leaflet bomb
- General Electric AN/APG-67