An air-to-air missile (AAM) is a guided missile used by one aircraft to try to destroy another aircraft. AAMs have evolved constantly since the first practical AAM, the AIM-9 Sidewinder, on which development started in 1950, the first drone was shot down in 1953, and a AIM-9B first made a combat kill in 1956. Interestingly, the basic Sidewinder has kept up with constant improvement; the AIM-9X entered production in 2004.
Air-to-air missiles have gone through a number of generations, as have jet fighters that they most frequently arm. The generations have been characterized by improvements in guidance, range, lethality, and the practical "engagement geometry" -- the relative angles between the firing aircraft and the target. While the basic guidance mechanisms remain "heat-seeking" infrared, electro-optical and various kinds of radars, the sensors have improved dramatically. The first AAMs had, by today's standards, primitive non-programmable control, a modern AAM will have extensive on-board computer power.
It can be useful to divide AAMs into two classes. Short-range AAMs are optimized for close combat, whether called dogfighting or air combat maneuvering. These are usually heat-seeking, with some electro-optical features.
A second class has Beyond Visual Range (BVR) capability, are not as maneuverable as the dogfighting missiles, and are usually radar-guided.
AAMs for close combat
As mentioned, the first successful AAM was the U.S. Navy's Sidewinder, although it had to overcome the usual interservice rivalry, with the Air Force's Falcon. Since the fifties, it has been convenient to group these missiles by generation.
|1||Attacker behind target; narrow field of seeker view||8km/5mi||early Sidewinders and [[Vympel K-13 (missile)]|Vympel K-13] (NATO: AA-2 ATOLL)|
|2||Attacker behind target; wider field of seeker view||8km/5mi||Vympel R-60M (NATO: AA-8 APHID)|
|3||"All-aspect"; still fairly narrow seeker view but not limited to rear attack||18km/11.3 mi||Israeli Python 3, AIM-9L Sidewinder|
|4||Much wider field of view, resistance to countermeasures. Some helmet-mounted electro-optical sights. Greatly improved maneuverability||Vympel R-73 (missile) (NATO: AA-11 Archer)|
|5||All aspect, able to find much smaller targets such as unmanned aerial vehicles (UAV) and cruise missiles. Treats the target as an image rather than a point, allowing targeting specific aircraft parts||>20 KM||AIM-9X Sidewinder, UK AIM-132 ASRAAM, Israeli Python 5|
Early radar missiles such as the AIM-7 Sparrow used semi-active radar homing (SARH), which required the firing aircraft to hold a radar beam on the target until the missile hit (or clearly missed). Pilots, understandably, felt vulnerable when they had to stay in a straight course heading for the hostile aircraft.
Many modern radar-guided AAMs also have a home-on-jam mode, turning an enemy aircraft's defensive systems into deathtraps. Final detonation can come from radar or infrared fuzes.
More recent missiles such as the French MBDA MICA, U.S. AIM-120 AMRAAM, the Russian Vympel R-77 (NATO reporting name: AA-12 ADDER) have active radar homing and are "fire-and-forget"; the launching aircraft can maneuver as soon as it fires. Some upgrades, such as the proposed long-range variant to the R-77, which will add a ramjet second stage, may use inertial or command guidance for the initial and midcourse part of their flight.
Extremely long range versions such as the Russian Novator R-172 and Network Centric Airborne Defense Element (NCADE) have specialized roles, but either might be converted to the other. The R-172 was probably built as an "AWACS killer", for engaging high-value assets such as C3I-ISR aircraft, cruise missile carriers, and tankers, which are usually well-defended. In contrast, the NCADE is primarily intended as an anti-ballistic missile, specifically as the first near-operational air-launched missile capable of boost phase intercept.
- Parsch, Andreas, "Raytheon (Philco/General Electric) AAM-N-7/GAR-8/AIM-9 Sidewinder", Designation-Systems.Net