Air to Air Combat a.k.a Dogfighting
Since World War II there have been many cases of air-to-air combat. Even in the jet age, modern air-to-air combat can develop into dogfights. A fighter can evade a missile by abrupt maximum-performance turns and employing countermeasures—such as chaff and flares—provided they can detect the missile via a radar warning receiver (RWR) or visually. If beyond-visual-range (BVR) missiles can be defeated, pilots can press the attack and very quickly arrive at the within-visual-range (WVR) arena. This will typically result in a high-speed neutral pass (or merge) from which the opposing pilots must decide to turn and continue the fight with their opponent or continue straight and 'bug-out'. The turning fight that develops can be commonly called a dog fight, or air combat maneuvering (ACM).
Superiority in a dog fight can depend on a pilot's experience and skill, and the agility of his fighter when flown at minimum air speeds approaching loss of control (causing a danger of stalling); the winner typically plays to the strengths of his own aircraft while forcing his adversary to fly at a design disadvantage. Dogfights are generally contests fought at low airspeeds, while maintaining enough energy for violent acrobatic maneuvering, as pilots attempt to remain within air speeds with a maximum turn rate and minimum turn radius: the so-called "corner speed" that often lies between 300 and 400 knots, depending on the aircraft's design. Therefore a dogfight has nothing to do with supersonic speed, but much to do with the engine power that makes supersonic flight possible. The super maneuverable F-22 Raptor can stand on its steerable nozzles at less than 100 knots airspeed, yet quickly maneuver to bring its M-61 Vulcan cannon to bear on a nearby evasive target, while an F-15 Eagle is more likely to use its thrust to maintain its relatively high corner speed, working to counter the drag caused by tight turns.
The continued importance of maintaining dogfighting proficiency was demonstrated during the Vietnam War. American pilots flew aircraft such as the F-4 Phantom II, equipped with long-range AIM-7 Sparrow missiles and AIM-9 Sidewinder missiles. However, air crews were required not to fire any missiles without having visually identified the target first, to make absolutely sure they were not an ally, thus losing this technological advantage. The AIM-7 missile was also not very reliable, making heavy use of delicate components such as vacuum tubes, which could not endure tropical climates, carrier takeoffs, and high-G maneuvers. Also, they had semi-active radar homing, meaning that they used the carrier plane's radar signals to home in on the target. The missiles themselves did not have a radar system, but "listened" to the pings of the attacker's radar and used the reflection of the prey aircraft to home in on it. AIM-9 missile were heat-seeking fire-and-forget missiles, meaning that once they had a lock on a heat source, they would attempt to hit it. They were only useful in short range, and in many cases failed, due to a number of factors, including delicate instruments and false heat sources (such as the sun). Additionally, early versions of the F-4 (prior to the E model) relied solely on missiles, having no guns nor lead-computing Gyro gunsight, and were therefore very vulnerable in the gun-range combat that could ensue.
Lightweight, short-endurance, point-defense fighters such as the MiG-17 and MiG-21 are typically far more agile than heavy, long-range, fighter-bombers (see the F-105 Thunderchief). Still, using superior tactics, the AIM-9 Sidewinder short-range missiles, and cannon fire, American pilots were able to gain significant victories in the air over North Vietnam, especially after the 1969 establishment of the United States Navy Fighter Weapons School (TOPGUN) to restore dogfighting ability to its pilots. At this school, pilots learned to exchange airspeed for altitude, using maneuvers like the Immelman turn and the Split-S, and to master tricks that put them behind an enemy fighter, where the enemy is vulnerable to heat-seeking Sidewinder missiles. Referring back the previous section, which focused on tactics developed during World War II, the North Vietnamese MiG-17 resorted to use of the Lufbery maneuver on occasion when cornered by faster F-4 Phantom fighters. Whereas the Thach Weave is used as aircraft move towards a point in space, the Lufbery is employed over a fixed point. With modern Radar guided air-to-air missiles like the AMRAAM greatly extending the general engagement range of jet fighters, some experts hypothesize that dogfighting may be headed toward extinction, but others cite the occurrences in Vietnam as evidence otherwise. However, it is worth noting that there have been a great number of Beyond-Visual-Range (BVR) kills occurring during and after Operation Desert Storm. This was due to the improved reliability of BVR missiles, radars, and most importantly, the integration of C3I assets such as AWACS aircraft into the realm of aerial warfare. This provided Coalition forces with a superior picture of the battlefield and in conjunction with airspace management allowed utilization of BVR weaponry.
Despite this the improvement of all-aspect IR, missiles coupled with helmet-mounted sights, has reduced the necessity of tail-chase attacks. In addition, Russian development of tail-mounted radar and rear-firing missiles has reduced Russian planes' vulnerability to tail-chase attacks. Yet because this feature is only present on the most modern jets, and missiles are a finite resource, the US Navy (TOPGUN) and the US Air Force (Red Flag) continue to teach postgraduate-level classes in air-combat-maneuvering engagements. Russian aircraft manufacturers heavily emphasize supermaneuverability and dogfight capabilities in fighter design, with aircraft such as the Su-37 or the Su-30MKI demonstrating advanced thrust vectoring systems to achieve these goals, pushing the aircraft to its limits to give it an advantage in combat. USAF fighters, such as the F-15 and F-16, tend to favor higher speeds, because of their emphasis on high power-to-weight ratio and low wing-loading; although the F-22 has supermaneuverability with its own vectored thrust.