First generation subsonic jet fighters (mid-1940s to mid-1950s)

The first generation of jet fighters comprises the initial, subsonic jet fighter designs introduced late in World War II and in the early post-war period. They differed little from their piston-engined counterparts in appearance, and many employed unswept wings. Initially, guns remained the principal armament. The main impetus for the development of turbojet-powered was to obtain a decisive advantage in maximum speed. Top speeds for fighters rose steadily throughout WWII as more powerful piston engines were developed, and had begun approaching the transonic flight regime where the efficiency of piston-driven propellers drops off considerably.

Messerschmitt Me 262A at the National Museum of the United States Air Force

The first jets were developed during World War II and saw combat in its final year. Messerschmitt developed the first operational jet fighter, the Me 262. It was considerably faster than contemporary piston-driven aircraft, and in the hands of a competent pilot, was quite difficult for Allied pilots to defeat. The design was never deployed in numbers sufficient to stop the Allied air campaign, and a combination of fuel shortages, pilot losses, and technical difficulties with the engines kept the number of sorties low. Nevertheless, the Me 262 indicated the obsolescence of piston-driven aircraft. Spurred by reports of the German jets, Britain's Gloster Meteor entered production soon after and the two entered service around the same time in 1944. Meteors were commonly used to intercept the V-1 "buzz bomb", as they were faster than available piston-engined fighters. By the end of the war almost all work on piston-powered fighters had ended. A few designs combining piston and jet engines for propulsion – such as the Ryan FR Fireball – saw brief use, but by the end of the 1940s virtually all new combat aircraft were jet-powered.

Despite their advantages, the early jet fighters were far from perfect, particularly in the opening years of the generation. Their operational lifespans could be measured primarily in hours; the engines themselves were fragile and bulky, and power could be adjusted only slowly. Many squadrons of piston-engined fighters were retained until the early-to-mid 1950s, even in the air forces of the major powers (though the types retained were the best of the WWII designs). Innovations including ejector seats and all-moving tailplanes were introduced in this period.

The Americans were one of the first to begin using jet fighters post-war. The Lockheed P-80 Shooting Star (soon re-designated F-80) was less elegant than the swept-wing Me 262, but had a cruise speed (660 km/h [410 mph]) as high as the combat maximum of many piston-engined fighters. The British designed several new jets, including the iconic de Havilland Vampire which was sold to the air forces of many nations.

Ironically, the British transferred the technology of the Rolls-Royce Nene jet engine technology to the Soviets, who soon put it to use in their advanced Mikoyan-Gurevich MiG-15 fighters which were the first to introduce swept wings in combat, an innovation first proposed by German research which allowed flying much closer to the speed of sound than straight-winged designs such as the F-80. Their top speed of 1,075 km/h (668 mph) proved quite a shock to the American F-80 pilots who encountered them over Korea, along with their armanent of two 23 mm cannons and a single 37 mm cannon compared to machine guns. Nevertheless, in the first jet-versus-jet dogfight in history, which occurred during the Korean War on 8 November 1950, an F-80 (as the P-80 had been redesignated) intercepted two North Korean MiG-15s near the Yalu River and shot them down.

A de Havilland Sea Vampire Mk.10 taking off from the Royal Navy aircraft carrier HMS Ocean on 3 December 1945, the occasion of the first take-off and landing of a jet airplane from an aircraft carrier

The Americans responded by rushing their own swept-wing F-86 squadrons to battle against the MiGs which had similar trans-sonic performance. The two aircraft had different strengths, but were similar enough that the superior technology such as a radar ranging gunsight and skills and of the veteran United States Air Force pilots allowed them to prevail.

The world's navies also transitioned to jets during this period, despite the need for catapult-launching of the new aircraft. Grumman's F9F Panther was adopted by the U.S. Navy as their primary jet fighter in the Korean War period, and it was one of the first jet fighters to employ an afterburner. The de Havilland Vampire was the Royal Navy's first jet fighter. Radar was used on specialized night fighters such as the F3D Skyknight which also downed MiGs over Korea, and later fitted to the F2H Banshee and swept wing F7U Cutlass and F3H Demon as all-weather / night fighers. Early versions of Infra-red (IR) air-to-air missiles (AAMs) such as the AIM-9 Sidewinder and radar guided missiles such as the AIM-7 Sparrow which would be developed into the 21st century were first introduced on swept wing subsonic Demon and Cutlass naval fighters.

Notable first generation jet fighter aircraft

 

MD450 Ouragan in the markings of India's No. 47 "Black Archers" Squadron

•  Canada
  • Avro CF-100 Canuck

•  France
  • Dassault Ouragan
  • Dassault Mystère
  • Dassault Mystère IV

 

Captured Heinkel He 162 undergoing post-war trials in the U.S.

• Nazi Germany
  • Heinkel He 162
  • Messerschmitt Me 262

•  People's Republic of China
  • Shenyang J-5 'Fresco'

•  Sweden
  • Saab 21R
  • Saab 29 Tunnan

A MiG-15 in Polish markings

•  Soviet Union
  • Mikoyan-Gurevich MiG-9 'Fargo'
  • Mikoyan-Gurevich MiG-15 'Fagot'
  • Mikoyan-Gurevich MiG-17 'Fresco'
  • Lavochkin La-15 'Fantail'
  • Yakovlev Yak-15/17 'Feather'
  • Yakovlev Yak-23 'Flora'
  • Yakovlev Yak-25 'Flashlight'

RAF Gloster Meteor

•  United Kingdom
  • de Havilland Vampire
  • de Havilland Venom
  • Gloster Meteor
  • Hawker Sea Hawk
  • Supermarine Attacker

F-86 Sabres of the Pakistan Air Force

F9F Panther and AJ-2 Savage conducting in-flight refueling trials in 1953

•  United States
  • Bell P-59 Airacomet
  • Lockheed P-80 Shooting Star
  • Republic F-84 Thunderjet
  • Republic F-84F Thunderstreak
  • North American F-86 Sabre
  • Northrop F-89 Scorpion
  • Lockheed F-94 Starfire
  • North American FJ-1 Fury
  • North American FJ-2/3/4 Fury
  • McDonnell F2H Banshee
  • McDonnell F3H Demon
  • Douglas F3D Skyknight
  • Douglas F4D Skyray
  • Vought F7U Cutlass
  • Grumman F9F Panther

Second generation jet fighters (mid-1950s to early 1960s)

North American F-100 Super Sabre day fighter

The Mirage IIIO and DO (top) were licence-built variants of the Mirage IIIE and D produced by Government Aircraft Factories (GAF) for the Royal Australian Air Force

Republic F-105 Thunderchief fighter-bomber

Early-model Mikoyan-Gurevich MiG-21F-13 'Fishbed-B' day fighter of the Vietnam People's Air Force captured by the Americans

Saab 32 Lansen fighter-bomber

Hawker Hunter fighter-bomber

English Electric Lightning

The development of second-generation fighters was shaped by significant technological breakthroughs, lessons learned from the aerial battles of the Korean War, and a growing focus on conducting operations in a nuclear warfare environment. Technological advances in aerodynamics, propulsion and aerospace building materials (primarily aluminium alloys) permitted designers to experiment with a variety of aeronautical innovations, such as swept wings, delta wings, and area-ruled fuselages. Widespread use of afterburning turbojet engines made these the first production aircraft to break the sound barrier, and the ability to sustain supersonic speeds in level flight became a common capability amongst fighters of this generation.

Fighter designs also took advantage of new electronics technologies that made effective radars small enough to be carried aboard smaller aircraft. Onboard radars permitted detection of enemy aircraft beyond visual range, thereby improving the handoff of targets by longer-ranged ground-based warning and tracking radars. Similarly, advances in guided missile development allowed air-to-air missiles to begin supplementing the gun as the primary offensive weapon for the first time in fighter history. During this period, passive-homing infrared-guided (IR) missiles became commonplace, but early IR missile sensors had poor sensitivity and a very narrow field of view (typically no more than 30°), which limited their effective use to only close-range, tail-chase engagements. Radar-guided (RF) missiles were introduced as well, but early examples proved unreliable. These semi-active radar homing (SARH) missiles could track and intercept an enemy aircraft "painted" by one's own aircraft's onboard radar. Medium- and long-range RF air-to-air missiles promised to open up a new dimension of "beyond-visual-range" (BVR) combat, and much effort was placed in further development of this technology.

The prospect of a potential third world war featuring large mechanized armies and nuclear weapon strikes led to a degree of specialization along two design approaches: interceptors (like the English Electric Lightning and Mikoyan-Gurevich MiG-21F) and fighter-bombers (such as the Republic F-105 Thunderchief and the Sukhoi Su-7). Dogfighting, per se, was de-emphasized in both cases. The interceptor was an outgrowth of the vision that guided missiles would completely replace guns and combat would take place at beyond visual ranges. As a result, interceptors were designed with a large missile payload and a powerful radar, sacrificing agility in favor of high speed, altitude ceiling and rate of climb. With a primary air defense role, emphasis was placed on the ability to intercept strategic bombers flying at high altitudes. Specialized point-defense interceptors often had limited range and little, if any, ground-attack capabilities. Fighter-bombers could swing between air superiority and ground-attack roles, and were often designed for a high-speed, low-altitude dash to deliver their ordnance. Television- and IR-guided air-to-surface missiles were introduced to augment traditional gravity bombs, and some were also equipped to deliver a nuclear bomb.

•  France
  • Dassault Étendard IV
  • Dassault Super Mystère
  • Dassault Mirage III/5
•  India
  • HAL HF-24 Marut
•  Israel
  • IAI Nesher
•  Italy
  • Fiat G.91
•  People's Republic of China
  • Shenyang J-6 'Farmer'
  • Chengdu J-7 'Fishbed'
•  Sweden
  • Saab 32 Lansen
  • Saab 35 Draken
•  Soviet Union
  • Mikoyan-Gurevich MiG-19 'Farmer'
  • Mikoyan-Gurevich MiG-21F 'Fishbed'
  • Sukhoi Su-7 'Fitter-A'
  • Sukhoi Su-9/11 'Fishpot'
•  United Kingdom
  • De Havilland Sea Vixen
  • English Electric Lightning
  • Gloster Javelin
  • Hawker Hunter
  • Supermarine Scimitar
  • Supermarine Swift
•  United States
  • Chance-Vought F-8 Crusader
  • Grumman F-9 Cougar
  • Grumman F-11 Tiger
  • North American F-100 Super Sabre
  • McDonnell F-101 Voodoo
  • Convair F-102 Delta Dagger
  • Lockheed F-104 Starfighter
  • Republic F-105 Thunderchief
  • Convair F-106 Delta Dart

Fourth generation jet fighters (circa 1970 to mid-1990s)

Mikoyan MiG-31 'Foxhound'

Grumman F-14 Tomcat

Sukhoi Su-27 'Flanker'

Dassault Mirage 2000

Mikoyan MiG-29 'Fulcrum' and F-16 Fighting Falcon

Panavia Tornado ADV

AIDC F-CK-1 Ching-kuo

Fourth-generation fighters continued the trend towards multirole configurations, and equipped with increasingly sophisticated avionics and weapon systems. Fighter designs were significantly influenced by the Energy-Maneuverability (E-M) theory developed by Colonel John Boyd and mathematician Thomas Christie, based upon Boyd's combat experience in the Korean War and as a fighter tactics instructor during the 1960s. E-M theory emphasized the value of aircraft specific energy maintenance as an advantage in fighter combat. Boyd perceived maneuverability as the primary means of getting "inside" an adversary's decision-making cycle, a process Boyd called the "OODA loop" (for "Observation-Orientation-Decision-Action"). This approach emphasized aircraft designs that were capable of performing "fast transients" – quick changes in speed, altitude, and direction – as opposed to relying chiefly on high speed alone.

E-M characteristics were first applied to the F-15 Eagle, but Boyd and his supporters believed these performance parameters called for a small, lightweight aircraft with a larger, higher-lift wing. The small size would minimize drag and increase the thrust-to-weight ratio, while the larger wing would minimize wing loading; while the reduced wing loading tends to lower top speed and can cut range, it increases payload capacity and the range reduction can be compensated for by increased fuel in the larger wing. The efforts of Boyd's "Fighter Mafia" would result in General Dynamics' (now Lockheed Martin's) F-16 Fighting Falcon.

The F-16's maneuverability was further enhanced by its being intentionally designed to be slightly aerodynamically unstable. This technique, called "relaxed static stability" (RSS), was made possible by introduction of the "fly-by-wire" (FBW) flight control system (FLCS), which in turn was enabled by advances in computers and system integration techniques. Analog avionics, required to enable FBW operations, became a fundamental requirement and began to be replaced by digital flight control systems in the latter half of the 1980s. Likewise, Full Authority Digital Engine Controls (FADEC) to electronically manage powerplant performance were introduced with the Pratt & Whitney F100 turbofan. The F-16's sole reliance on electronics and wires to relay flight commands, instead of the usual cables and mechanical linkage controls, earned it the sobriquet of "the electric jet". Electronic FLCS and FADEC quickly became essential components of all subsequent fighter designs.

Other innovative technologies introduced in fourth-generation fighters include pulse-Doppler fire-control radars (providing a "look-down/shoot-down" capability), head-up displays (HUD), "hands on throttle-and-stick" (HOTAS) controls, and multi-function displays (MFD), all of which have become essential equipment. Composite materials in the form of bonded aluminum honeycomb structural elements and graphite epoxy laminate skins began to be incorporated into flight control surfaces and airframe skins to reduce weight. Infrared search-and-track (IRST) sensors became widespread for air-to-ground weapons delivery, and appeared for air-to-air combat as well. "All-aspect" IR AAM became standard air superiority weapons, which permitted engagement of enemy aircraft from any angle (although the field of view remained relatively limited). The first long-range active-radar-homing RF AAM entered service with the AIM-54 Phoenix, which solely equipped the Grumman F-14 Tomcat, one of the few variable-sweep-wing fighter designs to enter production.

Another significant revolution came in the form of a stronger reliance on ease of maintenance, which led to standardisation of parts, reductions in the numbers of access panels and lubrication points, and overall parts reduction in more complicated equipment like the engines. Some early jet fighters required 50 man-hours of work by a ground crew for every hour the aircraft was in the air; later models substantially reduced this to allow faster turn-around times and more sorties in a day. Some modern military aircraft only require 10 man-hours of work per hour of flight time, and others are even more efficient.

Aerodynamic innovations included variable-camber wings and exploitation of the vortex lift effect to achieve higher angles of attack through the addition of leading-edge extension devices such as strakes.

Unlike interceptors of the previous eras, most fourth-generation air-superiority fighters were designed to be agile dogfighters, (although though the Mikoyan MiG-31 and Panavia Tornado ADV are notable exceptions). The continually rising cost of fighters, however, continued to emphasize the value of multirole fighters. The need for both types of fighters led to the concept of the "high/low mix" which envisioned a high-capability – and high-cost – core of dedicated air-superiority fighters (like the F-15 and Sukhoi Su-27) supplemented by a much larger contingent of lower-cost multirole fighters (such as the F-16 and Mikoyan MiG-29).

Most fourth-generation fighter-bombers, such as the Boeing F/A-18 Hornet and Dassault Mirage 2000, are true multirole warplanes, designed as such from the start. This was facilitated by multimode avionics which could switch seamlessly between air and ground modes. The earlier approaches of adding on strike capabilities or designing separate models specialized for different roles generally became passé (with the Panavia Tornado being an exception in this regard). Dedicated attack roles were generally assigned either to interdiction strike aircraft such as the Sukhoi Su-24 and Boeing F-15E Strike Eagle or to armored "tank-plinking" close air support (CAS) specialists like the Fairchild-Republic A-10 Thunderbolt II and Sukhoi Su-25.

Perhaps the most novel technology to be introduced for combat aircraft was "stealth", which involves the use of special "low-observable" (L-O) materials and design techniques to reduce the susceptibility of an aircraft to detection by the enemy's sensor systems, particularly radars. The first stealth aircraft to be introduced were the Lockheed F-117 Nighthawk attack aircraft (introduced in 1983) and the Northrop Grumman B-2 Spirit bomber (which first flew in 1989). Although no stealthy fighters per se appeared amongst the fourth generation, some radar-absorbent coatings and other L-O treatments developed for these programs are reported to have been subsequently applied to fourth-generation fighters.

Notable fourth generation jet fighter aircraft

•  France
  • Dassault Mirage 2000/2000N/2000D
•  People's Republic of China
  • Xian JH-7A 'Flounder'
  • Shenyang J-11A 'Flanker'
•  People's Republic of China /  Pakistan
  • JF-17 Thunder
•  Republic of China
  • AIDC F-CK-1 Ching-kuo
•  Soviet Union
  • Mikoyan MiG-29 'Fulcrum'
  • Mikoyan MiG-31 'Foxhound'
  • Sukhoi Su-27 'Flanker'
  • Sukhoi Su-33 'Flanker D'
•  United Kingdom /  Germany /  Italy
  • Panavia Tornado ADV
•  United States
  • Grumman F-14 Tomcat
  • McDonnell Douglas / Boeing F-15 Eagle
  • General Dynamics / Lockheed Martin F-16 Fighting Falcon
  • McDonnell Douglas F/A-18 Hornet

A more fanciful acronym was Protection Against Threats, Real, Imagined, Or Theorized

(Also, Pointing At Targets, Real, Imagined, Or Theorized.) The symbol for Patriot is a drawing of a Revolutionary War-era Minuteman.