any type of aircraft that has been adapted for military use.

Aircraft have been a fundamental part of military power since the mid-20th century. Generally speaking, all military aircraft fall into one of the following categories: fighters, which secure control of essential airspaces by driving off or destroying enemy aircraft; bombers, which are larger, heavier, and less maneuverable craft designed to attack surface targets with bombs or missiles; ground-support, or attack, aircraft (attack aircraft), which operate at lower altitudes than bombers (bomber) and air-superiority fighters (fighter aircraft) and attack tanks, troop formations, and other ground targets; transport and cargo planes, big-bodied craft with large amounts of interior space for carrying weapons, equipment, supplies, and troops over moderate or long distances; and helicopters, which are rotary-winged aircraft used for ground support, to transport assault troops, and for short-distance transport and surveillance.

True military aviation began with the perfection of the navigable airship in the late 19th century and the airplane in the first decade of the 20th century. The brothers Wilbur and Orville Wright, who made the first powered, sustained, and controlled flights in an airplane on Dec. 17, 1903, believed such an aircraft would be useful mainly for military reconnaissance. When they received the first contract for a military airplane from the U.S. government in February 1908, it called for an aircraft capable of carrying two persons at a speed of at least 40 miles (64 kilometres) per hour for a distance of 125 miles. The aircraft they delivered in June 1909 was listed as “Airplane No. 1, Heavier-than-air Division, United States aerial fleet.”

Experiments with arming airplanes were made spasmodically after 1910, when August Euler took out a German patent on a machine-gun (machine gun) installation. Bombing techniques evolved simultaneously. Dummy bombs were dropped on a target in the form of a ship by the American designer Glenn Curtiss (Curtiss, Glenn Hammond) on June 30, 1910. This test was followed by the dropping of a real bomb and the devising of the first bombsight. In England the Royal Flying Corps (RFC) fitted some of its aircraft with bomb carriers, which consisted of a kind of pipe rack beside the observer's cockpit in which small bombs were retained by a pin. The pin was pulled out over the target by tugging on a string. It was primitive but it worked. The Naval Wing of the RFC subsequently attempted to drop torpedoes from Short and Sopwith seaplanes, with some success, and efforts were soon under way to develop means to launch and recover such craft on shipboard. In 1910–11 a Curtiss biplane had been flown from and onto wooden platforms erected over the decks of anchored U.S. Navy cruisers, and in May 1912 a pilot of the Naval Wing, RFC, flew a Short S.27 biplane from HMS Hibernia while the ship was steaming at 10.5 knots. The following year the old cruiser Hermes was fitted with a short deck from which seaplanes took off on wheeled trolleys that were fitted under their floats and dropped away as the machines became airborne.

Thus, by 1914, reconnaissance, bomber, and carrier-based aircraft all were evolving, and some had been used in combat. The first use of an airplane in war was on Oct. 23, 1911, during the Italo-Turkish War, when an Italian pilot made a one-hour reconnaissance flight over enemy positions near Tripoli, Libya, in a Blériot XI monoplane. The first bombing raid came nine days later, when a pilot dropped four grenades on Turkish positions. The first reconnaissance photographs of enemy positions were taken on Feb. 24–25, 1912, in the same conflict.

The finest of the zeppelins was the LZ-70; this craft was 740 feet (220 metres) long, was able to fly above 16,000 feet, and had a range of 7,500 miles. The LZ-70 was shot down late in the war, however, and large rigid (metal-framed) airships were never again employed as combat aircraft. Smaller, nonrigid airships were used throughout World War I by the British for antisubmarine patrol, convoy escort, and coastal reconnaissance, achieving a remarkable record of protecting coastal convoys from German submarines. They were revived by the U.S. Navy during World War II for the same use.

At the outbreak of World War I, heavier-than-air craft were used only for visual reconnaissance, since their feeble engines could carry little more than a pilot and, in some cases, an observer aloft. They soon proved their worth in this mission, however, and RFC aviators provided reconnaissance that enabled the British and French armies to counterattack in the decisive Battle of the Marne on Sept. 6–12, 1914, turning back the invading Germans just short of Paris.

More powerful engines and better aircraft designs soon made possible specialized reconnaissance aircraft that could fly at high altitudes to avoid interception. The Germans, for example, had Rumpler two-seaters in service by 1917 that could operate as high as 24,000 feet. Radios were carried aloft to permit aerial observers to spot and adjust artillery fire, at first with transmitters only and then, as radios became lighter, with receivers for two-way communication.

The solution to the problem emerged in the spring of 1915 in the form of an interrupter gear, or gun-synchronizing device, designed by the French engineer Raymond Saulnier. This regulated a machine gun's fire so as to enable the bullets to pass between the blades of the spinning propeller. The interrupter itself was not new: a German patent had been taken out on such a device by the Swiss engineer Franz Schneider before the war. The real breakthrough was made by Roland Garros, a famous sporting pilot before the war and a friend of Saulnier, who perceived that a machine gun fitted with such a device and mounted rigidly atop the fuselage could be aimed accurately simply by pointing the airplane in the desired direction. Though the French machine gun had a tendency to “hang fire,” so that steel deflector plates had to be fitted onto the rear of the propeller blades to prevent their being shot off, Saulnier quickly perfected his device and fitted it to Garros's Morane L monoplane. With this machine, Garros shot down three German aircraft on April 1, 13, and 18. Then, on April 19, Garros himself force-landed with a ruptured fuel line and was taken prisoner. His efforts to burn his aircraft failed, and the secrets of Saulnier's interrupter gear were laid bare. The Germans reacted quickly, putting the designer Anthony Fokker (Fokker, Anthony Herman Gerard) to work on a similar device. With Saulnier's gear as his inspiration (and perhaps drawing on earlier German work), Fokker swiftly came up with an efficient interrupter gear, which he fitted onto a monoplane of his own design—ironically, a copy of a French Morane. The result was the Fokker Eindecker (“monoplane”), which entered service in July 1915 and reigned supreme in the air over the Western Front until the following October—a period known among Allied aviators as the “Fokker Scourge.”

The Eindecker's mastery was ended by new versions of the French Nieuport with a machine gun mounted above the top wing, allowing it to fire clear of the propeller arc, and by British D.H.2 and F.E.2b pushers with nose-mounted guns. Though a superb flying machine, the Nieuport was limited by its light armament, while the two British machines had brought the aerodynamically inefficient pusher configuration to its limit and were soon outclassed. Thereafter, the pace of fighter development began to be set by improvements in engine design—a phenomenon that was to persist well into the jet age.

Though Germany fell decisively behind France and Britain in aircraft production in 1917, and thus lost the war in the air, perhaps the definitive single-seat fighter of World War I was the Fokker D.VII of 1918. Typically powered by a 160-horsepower Mercedes engine, the D.VII was a fabric-covered biplane that differed from others in having a sturdy fuselage structure of welded steel tubing. Armed with two machine guns, it had a top speed of 117 miles per hour. Even more powerful engines made two-seat fighters possible; the best of these was the British Bristol F.2b, powered by the 220-horsepower, water-cooled Rolls-Royce Falcon, a V-12 engine that gave the Bristol a top speed of almost 120 miles per hour. The F.2b was armed with a synchronized machine gun for the pilot and two flexible machine guns for the observer.

Since they had to carry heavy disposable loads over long distances in order to be effective, specialized bombers were slower to develop. The first bombing raids to achieve significant success (and the first to cross national boundaries) were mounted against the Zeppelin works at Friedrichshafen from Belgian bases by airmen of the Royal Naval Air Service (RNAS) on Oct. 8 and Nov. 21, 1914. However, their spectacular success owed more to the highly flammable nature of the zeppelins themselves than to the destructive power of the 20-pound bombs used. These raids prompted the Admiralty to commission the development of the first specialized heavy night bomber, the Handley Page H.P. O/100, which flew for the first time in December 1915. Meanwhile, other air forces began building and putting into service strategic day bombers. Among the first were French Voisins. The type L was used in early 1915 to carry about 130 pounds of small bombs that simply lay in the bottom of the cockpit until the time came for the observer to drop them overboard. Later models had more powerful engines and were equipped alternatively as attack aircraft, carrying up to 660 pounds of bombs or having a 37-millimetre gun mounted in the nose. None flew faster than 84 miles per hour, so the Voisins operated mainly under cover of darkness in the last year of the war.

The most efficient of the long-range coastal-based airplanes were large, twin-engined flying boats designed by Glenn Curtiss and others. Despite their bulk, these aircraft were sufficiently fast and maneuverable to engage enemy zeppelins and aircraft in combat. Curtiss' flying boats were the only aircraft of U.S. design to see frontline combat service in World War I.

Carrier-based air power also advanced rapidly. In early 1916 the first landplanes (British Sopwith Pups) were flown off the 200-foot decks of primitive carriers that had been converted from merchant ships, and on Aug. 2, 1917, a pilot landed a Pup on the takeoff deck of HMS Furious while the ship was under way. The concept of the true aircraft carrier had been born.

Britain went on to develop more formidable naval aircraft, and in October 1918 a squadron of Sopwith Cuckoos, each able to carry an 18-inch torpedo (torpedo plane), was embarked on HMS Argus. The war ended before the squadron could go into action; but the RNAS had already used torpedoes dropped from Short seaplanes to sink enemy ships in the Mediterranean, and the Cuckoo, with its modest top speed of 103 miles per hour and endurance of four hours, heralded the eventual demise of the battleship in the face of air-power dominance at sea.

Military air transport (aviation) showed little development in 1914–18. Aircraft were used on occasion to drop supplies to cut-off or besieged forces, but the methods were primitive in the extreme: bags of food, medical supplies, or munitions were dropped from bomb racks or simply heaved over the side.

Conversely, training made enormous strides during the war. At the RFC School of Special Flying at Gosport, Eng., Major Robert Smith-Barry introduced a curriculum based on a balanced combination of academic classroom training and dual flight instruction. Philosophically, Smith-Barry's system was based not on avoiding potentially dangerous maneuvers (as had been the case theretofore) but on exposing the student to them in a controlled manner so that he could learn to recover from them, thereby gaining confidence and skill. Technologically, it was based on the Avro 504J, a specialized training aircraft with dual controls, good handling characteristics, adequate power, and in-flight communication between instructor and student by means of an acoustic system of soft rubber tubing—the so-called Gosport tube. For the first time, military pilots flew into action as masters of their airplanes. The Gosport system of training was eventually adopted at training schools throughout the world, remaining the dominant method of civil and military flight instruction into the jet age.

In the two decades between the end of World War I and the start of World War II, military aviation underwent a complete transformation. The typical combat aircraft of 1918 was a fabric-covered, externally braced biplane with fixed landing gear and open cockpits. Few aero engines developed as much as 250 horsepower, and top speeds of 120 miles per hour were exceptional. By 1939, the first-line combat aircraft of the major powers were all-metal monoplanes with retractable landing gear. Powered by engines that developed 1,000 horsepower or more and that were supercharged to permit flight at altitudes above 30,000 feet, fighters were capable of exceeding 350 miles per hour, and some bombers flew faster than 250 miles per hour. Gyroscopically driven flight instruments and electrical cockpit lighting permitted flying at night and in adverse weather. Crews were seated in enclosed cockpits, were provided with oxygen for breathing at high altitudes, and could converse with other aircraft and ground stations by voice radio. Parachutes, worn by a few German fighter pilots in the last days of World War I, were standard equipment.

Most of these changes occurred after 1930. The end of World War I left the victorious Allies with huge inventories of military aircraft, and this combined with economic strictures and a lack of threat to retard the development of military aviation in the 1920s. Provisions of the Treaty of Versailles prohibiting developments in military aviation had the same effect in Germany. Nevertheless, advances in key technologies, notably high-performance aero engines, continued. The U.S. government, for instance, sponsored a systematic program of aerodynamic research under the aegis of the National Advisory Committee for Aeronautics (NACA), which was to yield enormous dividends in aircraft performance through drag-reduction, engine-cooling, and airfoil technologies. Still, the most significant technical advance in the 1920s was the abandonment of wooden structures in favour of metal frames (still fabric-covered) to provide the strength needed to cope with increasingly powerful engines and to resist harsh climates around the world.

When more drastic changes came, they emerged not from military requirements but from civilian air racing, particularly the international seaplane contests for the coveted Schneider Trophy. Until the appearance of variable-pitch propellers in the 1930s, the speed of landplanes was limited by the lengths of existing runways, since the flat pitch of high-speed propellers produced poor takeoff acceleration. Seaplanes, with an unlimited takeoff run, were not so constrained, and the Schneider races, contested by national teams with government backing, were particularly influential in pushing speeds upward. During the 1920s the Curtiss company built a remarkable series of high-speed racing biplanes for the U.S. Army Air Corps and Navy. These were powered by the innovative D-12, a 12-cylinder, liquid-cooled engine, also of Curtiss design, that set international standards for speed and streamlining. One of the Curtiss planes, an R3C-2 piloted by Lieutenant James Doolittle (Doolittle, James H.), won the 1925 Schneider race with a speed of 232.5 miles per hour—in sharp contrast to the winning speed of 145.62 miles per hour in 1922, before the Curtiss machines took part in the event. The influence of the Curtiss engine extended to Europe when British manufacturer C.R. Fairey, impressed with the streamlining made possible by the D-12, acquired license rights to build the engine and designed a two-seat light bomber around it. The Fairey Fox, which entered service in 1926, advanced the speed of Royal Air Force (RAF) bombers by 50 miles per hour and was faster than contemporary fighters. Nor were British engine manufacturers idle; when the U.S. Army and Navy standardized on air-cooled radial engines in the 1920s, Curtiss ceased developing liquid-cooled engines, but British engine designers, partly inspired by the D-12, embarked on a path that was to produce the superlative Rolls-Royce Merlin.

The year that Doolittle won the Schneider Trophy, an even more revolutionary design appeared—the S.4 seaplane designed by R.J. Mitchell (Mitchell, R.J.) of the British Supermarine Company. A wooden monoplane with unbraced wings, the S.4 set new standards for streamlining, but it crashed from wing flutter before it could demonstrate its potential. Nevertheless, it was the progenitor of a series of monoplanes that won the trophy three times, giving Britain permanent possession in 1931. The last of these, the S.6B, powered by a liquid-cooled Rolls-Royce racing engine with in-line cylinders, later raised the world speed record to more than 400 miles per hour. The S.6B's tapered fuselage and broad, thin, elliptical wings were clearly evident in Mitchell's later and most famous design, the Spitfire.

By the 1930s the advantages of monoplanes with unbraced wings and retractable landing gear were evident, and fighters of this description began to appear. The first of these to see operational service was the Soviet I-16, designed by Nikolay Polikarpov. The I-16 first flew in 1933 and enjoyed considerable success against German and Italian biplanes in the Spanish Civil War of 1936–39. Powered by a radial engine derived from the Wright Cyclone, it had manually retracted landing gear and an open cockpit; its armament of four 7.62-millimetre machine guns, two in the wings and two in the engine cowling, was heavy for the time.

By the 1930s, ship-based aircraft were fitted under the tail with arrester hooks that engaged cables strung across the landing deck in order to bring them to a halt after landing. Folding wings then enabled them to be taken by elevator to below-deck hangars. Japanese and U.S. aircraft carriers had mixed complements of single-seat fighters, dive-bombers, and torpedo planes; the Royal Navy pursued a less successful course, developing two-seat reconnaissance fighters, such as the Fairey Fulmar, which were outperformed by their land-based equivalents.

Air superiority was crucial to the outcome of most of the decisive campaigns of World War II, and here the performance of single-seat fighters was generally the critical factor. First-class fighters required extremely powerful aero engines suitable for compact, low-drag installation, and in this respect Britain, Germany, and the United States were in a class by themselves. The only significant exception was the Japanese Mitsubishi A6M carrier fighter, known as the Zero. Designed by Horikoshi Jiro, the Zero was so remarkably strong and light that it achieved first-class performance with a second-class engine—though at the cost of being vulnerable to battle damage.

By war's end, piston-engined fighter technology reached its peak in later versions of the Fw 190, powered by in-line Jumo engines by Junkers, and in the Hawker Tempest, powered by the massive 2,200-horsepower, 24-cylinder, in-line Napier Sabre. Armed with four 20-millimetre cannon and able to attain speeds in excess of 435 miles per hour, the Tempest was the fastest piston-engined fighter ever to see service.

During the Battle of Britain, the RAF converted twin-engined bombers such as the Bristol Blenheim into night fighters by installing offensive ordnance and radar, but these had little success, since they were no faster than their prey. On the other hand, Messerschmitt's Me 110, a disastrous failure as a twin-engined, two-seat day fighter, became highly successful at night fighting, as did similarly modified Ju 88 bombers. The RAF later used radar-equipped versions of the de Havilland Mosquito to protect its bombers during the battle for the night skies over Germany in 1943–45.

An independent British development was the de Havilland Mosquito. Constructed entirely of wood, powered by two Rolls-Royce Merlin engines, and carrying a crew of two and no defensive armament, this extraordinarily fast aircraft remained effectively immune to interception until the appearance of jet fighters, and it could reach Berlin with a 4,000-pound bomb. It was perhaps the most successful multimission aircraft ever made, serving with distinction as a low-level day bomber, radar-equipped night fighter, and long-range photoreconnaissance aircraft.

Land-based torpedo planes were also effective, as shown in attacks on the British battleships Repulse and Prince of Wales by twin-engine Japanese Mitsubishi G3M and G4M bombers off Malaya on Dec. 10, 1941.

For military staffs contemplating offensive operations, aerial photography became the most important source of detailed information on enemy dispositions. British reconnaissance aircraft were especially capable. Modified versions of the Spitfire and Mosquito, stripped of armament and fitted with extra fuel tanks, proved essentially immune to interception at high altitudes. Stripped-down versions of the P-38 and P-51, called the F-4 and F-5, were also effective photoreconnaissance platforms, the latter excelling at high-resolution coverage from low altitudes.

Major advances in air transport were made during the war. Mass drops of parachute troops had been pioneered by the Soviet Union in the 1930s, but the Luftwaffe first used the technique operationally, notably during the invasion of Crete, in which 15,000 airborne and parachute troops were landed onto that island by 700 transport aircraft and 80 gliders. The troop-carrying glider was one of the developments of World War II that had no continuing place in postwar air forces, but the transport airplane was only at the beginning of its useful life. The Germans built transports such as the Ju 52 only in small quantities, but the twin-engined Douglas C-47, which had revolutionized American commercial aviation in the mid-1930s as the DC-3, was produced in huge numbers and was the backbone of tactical air transport in every Allied theatre of the war. One of the few transports with a large side door suitable for dropping paratroopers, the C-47 was also the mainstay of British and American airborne operations. Douglas also manufactured the four-engined C-54, which entered service in 1943–44 as the first land-based transport with intercontinental flight capabilities. The C-54 was particularly important in the vast distances of the Pacific-Asian theatre of operations.

Though Whittle was first off the mark, the Germans advanced their programs with persistence and ingenuity. The Messerschmitt Me 262, powered by two Jumo engines and with wings swept back 18.5°, was capable of 525 miles per hour. Armed with four 30-millimetre cannon and unguided rockets, it was an effective bomber destroyer, but it entered service too late to have a major effect on the war. The Gloster Meteor entered service on July 27, 1944, about two months before the Me 262; though it was less capable than the German fighter, it was effective in intercepting V-1 “buzz bombs.” Desperate to combat Allied bombers, the Germans also turned to rocket propulsion, fielding the tailless Me 163 Komet in the final months of the war. Powered by a hydrogen peroxide rocket designed by Helmuth Walter, the Komet had spectacular performance, but its short range and ineffective cannon armament made it an operational failure. In addition, the propellants were unstable and often exploded on landing.

The jets of World War II inaugurated the first generation of jet fighters, in which turbojet propulsion was applied to existing airframe technology and aerodynamics. (Indeed, some early postwar jets—notably, the Soviets' Yakovlev Yak-15 and Yak-23 and the Swedish Saab 21R—were simply re-engined propeller-driven fighters.) These aircraft generally outperformed their piston-engined contemporaries by virtue of the greater thrust that their jets provided at high speeds, but they suffered from serious deficiencies in range and handling characteristics owing to the high fuel consumption and slow acceleration of early turbojets. More fundamentally, they were limited to subsonic speeds because the relatively thick airfoils of the day were prone to the compressibility problems of transonic flight—especially at high altitudes, where the higher speeds required to produce lift in thin atmosphere brought aircraft more quickly to transonic speed. For this reason, first-generation jets performed best at low altitudes.

Other first-generation fighters included the U.S. McDonnell FH Phantom and the British Hawker Sea Hawk (the first jet carrier fighters), the McDonnell F2H Banshee, and the French Dassault Ouragan. These single-seat day fighters were in service by 1950, while first-generation all-weather fighters, burdened with radar and a second crew member, entered service through the late 1950s.

As these developments took hold, a second generation of fighters appeared that were capable of operating in the transonic regime. These aircraft had thinner lifting and control surfaces than first-generation jets, and most had swept-back wings. Aerodynamic refinements and more powerful, quicker-accelerating engines gave them better flight characteristics, particularly at high altitudes, and some could exceed the Mach in a shallow dive. In addition, airborne radars became more compact and reliable, and radar-ranging gunsights began to replace the optically ranging sights used in World War II. Air-to-air missiles, using radar guidance and infrared homing, became smaller and more capable (see rocket and missile system: Tactical guided missiles (rocket and missile system)). Outstanding fighters of this generation were the U.S. North American F-86 Sabre and its opponent in the Korean War (1950–53), the Soviet MiG-15. The F-86 introduced the all-flying tail (later a standard feature on high-performance jets), in which the entire horizontal stabilizer deflects as a unit to control pitch, yielding greater control and avoiding the compressibility problems associated with hinged surfaces. This and a radar-ranging gunsight helped the F-86 achieve a favourable kill ratio over the MiG-15, despite the Soviet fighter's greater speed, higher service ceiling, and heavier armament. Other jets of this generation were Britain's superlative Hawker Hunter, the MiG-17, and the diminutive, British-designed Folland Gnat. The latter two, introduced in the mid-1950s, later became successful low-altitude dogfighters—the Gnat against Pakistani F-86s in the Indo-Pakistani conflict of 1965 and the MiG-17 against U.S. aircraft in the Vietnam War (1965–73).

A third generation of fighters, designed around more powerful, afterburning engines and capable of level supersonic fight, began to enter service in the mid-1950s. This generation included the first fighters intended from the outset to carry guided air-to-air missiles and the first supersonic all-weather fighters. Some were only marginally supersonic, notably the U.S. Convair F-102 Delta Dagger, an all-weather interceptor that was the first operational “pure” delta fighter without a separate horizontal stabilizer. Other aircraft included the Grumman F11F Tigercat, the first supersonic carrier-based fighter; the North American F-100 Super Sabre; the Dassault Mystère B-2; the Saab 35, with a unique double-delta configuration; and the MiG-19.

To this point, jet fighters had been designed primarily for air-to-air combat, while older aircraft and designs falling short of expectations were adapted to ground attack and reconnaissance. Since land-based surface attack was to be carried out by bombers, the first operational jets of fighter size and weight designed to attack surface targets were based on aircraft carriers. These paralleled the third generation of fighters, but they were not supersonic. One example was the British Blackburn Buccaneer, capable of exceptional range at low altitudes and high subsonic speeds. The Douglas A-4 Skyhawk, entering service in 1956, sacrificed speed for ordnance-delivery capability. One of the most structurally efficient aircraft ever built, it carried the burden of U.S. Navy attacks on ground targets in North Vietnam and was often used by Israeli pilots in the Middle Eastern conflicts. The A-4 Skyhawk was still in use with the Kuwaiti Air Force during the Persian Gulf War (1990–91), an astonishingly long service life. The Grumman A-6 Intruder, which entered service in the 1960s, was another subsonic carrier-based aircraft. The first genuine night/all-weather, low-altitude attack aircraft, it was highly successful over North Vietnam and continued to be in service until the late 1990s. The electronic warfare version, the E-6B, was projected to remain in service well into the 21st century.

A fourth generation of fighters began to appear in the 1960s, capable of maximum speeds ranging from about Mach 1.5 to 2.3. Top speeds varied with the intended mission, and increasing engine power, aerodynamic sophistication, and more compact and capable radars and avionics began to blur the differences between two-seat, all-weather fighters and single-seat air-superiority fighters and interceptors. By this time, military designers had become persuaded that air-to-air missiles had made dogfighting obsolete, so that many interceptors were built without guns. This generation included the first land-based jet fighters designed with surface attack as a secondary or primary mission—a development driven by the appearance of surface-to-air missiles such as the Soviet SA-2, which denied bombers medium- and high-altitude penetration.

The new generation of fighters was characterized by Mach 2+ performance where necessary, multimission capability, and sophisticated all-weather avionics. Many aircraft of this generation employed variable-geometry wings, permitting the amount of sweep to be changed in flight to obtain optimal performance for a given speed. Important aircraft in this generation included, roughly in order of operational appearance, the following: the MiG-25 Foxbat, a large single-seat interceptor and reconnaissance aircraft with a service ceiling of 80,000 feet and a top speed on the order of Mach 2.8 but with limited maneuverability and low-altitude performance; the MiG-23 Flogger, a variable-wing interceptor able to acquire and engage with missiles below it in altitude; the MiG-27 Flogger, a ground-attack derivative of the MiG-23; the Saab 37 Viggen, designed for short takeoff with a main delta wing aft and small delta wings with flaps forward; the fixed-wing Sepecat Jaguar, developed by a French-British consortium in ground-attack and interceptor versions; the Grumman F-14 Tomcat, a highly maneuverable, twin-engined, two-seat, variable-geometry interceptor armed with long-range missiles for the defense of U.S. aircraft-carrier fleets; the Dassault-Breguet Mirage F1, designed for multimission capability and export potential; the McDonnell Douglas F-15 Eagle, a single-seat, twin-engined, fixed-geometry air-force fighter designed for maximum sustained maneuvering energy (a concept developed by U.S. Air Force Colonel John Boyd) and the first possessor of a genuine “look-down/shoot-down” capability, which was the product of pulse-Doppler radars that could detect fast-moving targets against cluttered radar reflections from the ground; the Panavia Tornado, a compact, variable-geometry aircraft developed jointly by West Germany, Italy, and Great Britain in no fewer than four versions, ranging from two-seat, all-weather, low-altitude attack to single-seat air-superiority; the U.S. General Dynamics F-16 Fighting Falcon, a high-performance, single-seat multirole aircraft with impressive air-to-ground capability; the MiG-29 Fulcrum, a single-seat, twin-engined, fixed-geometry interceptor with a look-down/shoot-down capability; the MiG-31 Foxhound interceptor, apparently derived from the MiG-25 but with less speed and greater air-to-air capability; and the McDonnell Douglas F/A-18 Hornet, a single-seat, carrier-based aircraft designed for ground attack but also possessing excellent air-to-air capability.

The British “V-bombers,” introduced in the 1950s, comprised the Vickers Valiant, Handley Page Victor, and Avro Vulcan. These served as the backbone of Britain's nuclear deterrent until superseded by Polaris-missile-equipped nuclear submarines in the 1970s. The Vulcan, the first jet bomber to use the delta-wing configuration, remained in service long enough to drop conventional bombs in the Falkland Islands War.

The first Soviet jet bombers with strategic potential were the twin-engined Tupolev Tu-16 Badger (deployed in 1954) and the larger and less successful four-engined Myasishchev M-4 Bison (deployed in 1956). In 1956 the Soviets also fielded the only turboprop strategic bomber to see service, the Tu-95 Bear. A large, swept-wing aircraft powered by four huge turboprop engines with contrarotating propellers, the Tu-95 proved to have excellent performance. Like the B-52, it was adapted to maritime and cruise missile patrol after it had become obsolete as a strategic bomber.

The aircraft mentioned above were capable of only subsonic speeds. The first operational supersonic bomber was the delta-winged Convair B-58 Hustler of the United States. Placed in active service in 1960, this bomber carried its nuclear weapon and most of its fuel in a huge, jettisonable pod beneath the fuselage.

Larger strategic bombers using variable geometry to achieve high performance at low altitudes included the Soviet Tu-22 Backfire, the U.S. Rockwell International B-1, and the Tu-160 Blackjack. These bombers, supplementing the older purely subsonic aircraft, formed an important part of the U.S. and Soviet nuclear forces after their deployment in 1975, 1985, and 1988, respectively. In common with all first-line combat aircraft, they were equipped with sophisticated electronic countermeasure (ECM) equipment designed to jam or deceive enemy radars. They could deliver free-fall conventional or nuclear bombs, air-to-surface missiles, and cruise missiles. The B-1B version could achieve supersonic flight only in short bursts at high altitude, while the Soviet bombers were capable of supersonic “dash” at low level and could fly at twice the speed of sound at high altitude.

The existence of a Stealth program, designed to produce aircraft that were effectively immune to radar detection at normal combat ranges, was announced by the U.S. government in 1980. The first aircraft employing this technology, the single-seat Lockheed F-117A (F-117) ground-attack fighter, became operational in 1983. The second was the Northrop B-2 strategic bomber, which first flew in 1989. Both aircraft had unconventional shapes that were designed primarily to reduce radar reflection. The B-2 was of a flying-wing design that made it only slightly longer than a fighter yet gave it a wingspan approaching that of the B-52, while the F-117A had a short, pyramid-shaped fuselage and sharply swept wings.

Ever since radar-directed defenses began taking a toll of bomber formations in World War II, aircraft designers and military aviators had sought ways to avoid radar detection. Many materials of the early jet age were known to absorb radar energy rather than reflect it, but they were heavy and not strong enough for structural use. It was not until after the 1960s and '70s, with the development of such materials as carbon-fibre composites and high-strength plastics (which possessed structural strength as well as being transparent or translucent to radar), that radar signature reduction for piloted combat aircraft became possible.

Reducing radar signature also required controlling shape, particularly by avoiding right angles, sharp curves, and large surfaces. In order to direct radar energy in the least revealing directions, the external shape of a stealth aircraft was either a series of complex, large-radius, curved surfaces (as on the B-2) or a large number of small, flat, carefully oriented planes (as on the F-117A). Fuel and ordnance were carried internally, and engine intakes and exhausts were set flush or low to the surface. To avoid interception of radar emissions, stealth aircraft had to rely on inertial guidance or other nonemitting navigational systems. Other possibilities included laser radar, which scanned the ground ahead of the craft with a thin, almost undetectable laser beam.

To escape detection in the infrared spectrum, first-generation stealth aircraft were not equipped with large, heat-producing afterburner engines. This rendered them incapable of supersonic flight. Also, the shapes and structures optimal for stealth aircraft were often at odds with aerodynamic and operational requirements. Since all weaponry had to be carried internally, ordnance loads were less than for equivalent conventional aircraft, and sophisticated artificial stabilization and control systems were needed to give stealth aircraft satisfactory flying characteristics. Unlike the fighter, the B-2 had no vertical fin stabilizers, relying on flaps on the trailing edge of its notched wing to control roll, pitch, and yaw. A second-generation stealth aircraft, the U.S. Air Force F-22 Raptor, which first flew in 1997, is capable of supersonic speeds without afterburning.

Carrier-based early-warning aircraft had a large radar to detect aircraft or ships; some could also control interceptor fighters defending the fleet. This kind of airborne warning and control system ( AWACS) airplane appeared in land-based air forces to detect low-flying enemy raiders and direct interceptors toward them. The first aircraft of this type was a Soviet turboprop, the Tu-126 Moss, which was succeeded in the 1980s by the jet-powered Ilyushin Il-76 Mainstay. These craft, like the U.S. E-3 Sentry (a converted Boeing 707), carried a large, saucer-shaped radar on the fuselage. Britain's early-warning aircraft (aviation) was the British Aerospace Nimrod.

The helicopter had its first significant impact on military operations during the Korean War, but it came of age in Vietnam. Helicopters fielded air-mobile infantry units, evacuated casualties, hauled artillery and ammunition, rescued downed aviators, and served as ground-attack craft. Helicopters became serious operational machines only after American manufacturers fitted them with gas-turbine engines (gas-turbine engine), which were much less sensitive than piston engines to high temperatures and low atmospheric density, had far greater power-to-weight ratios, and occupied considerably less space.

The successor to the HueyCobra was the McDonnell Douglas AH-64 Apache, a heavily armoured antiarmour helicopter with less speed and range than the Hind but with sophisticated navigation, ECM, and fire-control systems. The Apache became operational in 1986 and proved highly effective in the Persian Gulf War (1990–91).

Helicopters were used extensively in antisubmarine roles, “dipping” sonar sensors into the water to locate their targets and launching self-homing torpedoes to destroy them. Ship-borne helicopters also served as firing platforms for antiship missiles and were used to carry warning and surveillance radars, typically sharing information with their mother ships. By firing heat-producing or chaff flares to confuse infrared and radar homing systems, naval helicopters could serve as decoys for antiship missiles.

The first remotely piloted vehicles (RPVs) were small, pilotless aircraft controlled by command radio transmission. Most of these fell into one of two categories: extremely high-performance drones used to test new systems; and small, relatively inexpensive drones used for training. Both were typically reusable, being recovered by radio-controlled landing or, more commonly, by parachute. Target drones were commonly fitted with radar reflectors to stimulate the radar return of enemy aircraft, and it soon occurred to strategists to use them as decoys to assist bombers (bomber) in penetrating enemy defenses. That modified target drones might be effective platforms for communications relay and for sensor and reconnaissance systems also became evident. The Ryan QM-34 Firebee, a photoreconnaissance modification of a standard U.S. target drone, saw extensive service in Vietnam. A swept-wing, turbojet-powered subsonic vehicle less than half the size of a jet fighter, the Firebee penetrated heavily defended areas at low altitudes with impunity by virtue of its small radar cross section and brought back strikingly clear imagery. Indicative of later development was the Boeing Compass Cope, a long-winged, subsonic, turbofan-powered drone capable of long flights at extremely high altitudes.