How MiG-21 shot down Pakistan’s F-16 by R-73 missile in 90-second
https://www.globalsecurity.org/military/world/russia/aa-11.htm
AA-11 ARCHER R-73
The AA-11 NATO Archer is a short-range infrared guided missile system employed by the MIG-29 and the SU-27. Its advanced control surfaces and thrust vectoring, coupled with excellent off-boresight capability and the pilot's helmet-mounted sight may give it unparalleled performance in the close-in, visual dogfight.
As the Soviet Union fell behind the West in the fields of electronics and computational power, their ability to field advanced radar systems declined. As a result, the Soviets increasingly relied on more reliable, easier to design, computationally simpler, and tougher-to-jam IR systems, which surprised Western intelligence agencies. For example, when the MiG-29 Fulcrum aircraft was fielded in the 1980s, its radar system and associated missile were impressive by Soviet standards but at least a generation behind Western systems. However, it also had a bump on the nose, which was not an electronic warfare antenna as first suspected, but an Infrared Search and Track System (IRST), which was the first to be fielded in an operational fighter.
Once merged with a laser range finder, the IR system could detect aircraft and provide targeting data at longer ranges without alerting the target aircraft that it had been detected. Even if a target aircraft suspected it was being tracked, there is no practical way to “jam” this IR system. The MiG-29’s IR system was integrated with the improved IR missile, known as the AA-11 Archer, which not only had the all-aspect feature of the latest Sidewinders, but it also had “off-boresight” capability – meaning that the missile could “look” to its left and right to “see” target aircraft.
Thus, the pilot could fire a missile without pointing the aircraft nose at the target aircraft, as Sidewinder equipped pilots must do. This expands the firing envelope for the missile, saves precious seconds in a dogfight, and compliments the maneuverability of a fighter because it is much easier to maneuver the fighter into a firing position. In addition, Russian pilots had a helmet-mounted thermal sight which permitted them to aim the missile merely by looking at the targeted aircraft, in effect giving them an IR “heads-up display” wherever they looked, not just on the front of the instrument panel, as in Western cockpits. The details of this system did not fully emerge until the East German MiG-29’s became part of the unified Germany’s Luftwaffe. Once they did, it was clear that an IR-equipped MiG-29, flown by a skilled pilot, had an advantage, and the AA-11 Archer missile seriously challenges the technological primacy of the Sidewinder.
Currently the R-73 is the best Russian short range air-to-air missile. Apart from an exceptional maneverability, this missile is also directly connected to the pilot's helmet, which allows engagement of targets lateral to the aircraft, which cannot be engaged by missiles with a traditional system of targeting and guidance. The R-73A, an earlier variant of this missile, has a 30 km range, while the most recent R-73M can hit targets at a distance of 40 km.
The R-73 short-range, close-combat standardized missile was developed in the Vympel Machine Building Design Bureau, and became operational in 1984. The R-73 is included in the weapon complex of MiG-23MLD, MiG-29 and Su-27 fighters and their modifications and also of Mi-24, Mi-28 and Ka-50 helicopters. It also can be employed in flying craft which do not have sophisticated aiming systems.
The missile is used for engaging modern and future fighters, attack aircraft, bombers, helicopters, drones and cruise missiles, including those executing a maneuver with a g-force up to 12. It permits the platform to intercept a target from any direction, under any weather conditions, day or night, in the presence of natural interference and deliberate jamming. It realizes the "fire and forget" principle.
The missile design features a canard aerodynamic configuration: control surfaces are positioned ahead of the wing at a distance from the center of mass. The airframe consists of modular compartments accommodating the homing head, aerodynamic control surface drive system, autopilot, proximity fuze, warhead, engine, gas-dynamic control system and aileron drive system. The lifting surfaces have a small aspect ratio. Strakes are mounted ahead of the aerodynamic control surfaces. The combined aero-gas-dynamic control gives the R-73 highly maneuverable flight characteristics. During flight, yaw and pitch are controlled by four aerodynamic control surfaces connected in pairs and by just as many gas-dynamic spoilers (fins) installed at the nozzle end of the engine.