The AIM-9 Sidewinder is a supersonic, heat-seeking, air-to-air missile carried by
fighter aircraft. It has a high-explosive warhead and an active infrared guidance system.
The Sidewinder was developed by the U.S. Navy for fleet air defense and was adapted by the
U.S. Air Force for fighter aircraft use. Early versions of the missile were extensively
used in the Southeast Asian conflict.
The AIM-9 has a cylindrical body with a roll-stabilizing rear wing/rolleron assembly.
Also, it has detachable, double-delta control surfaces behind the nose that improve the
missile's maneuverability. Both rollerons and control surfaces are in a cross-like
The missile's main components are an infrared homing guidance section, an active optical
target detector, a high-explosive warhead, and a rocket motor.
The infrared guidance head enables the missile to home on target aircraft engine
exhaust. An infrared unit costs less than other types of guidance systems, and can be used
in day/night and electronic countermeasures conditions. The infrared seeker also permits
the pilot to launch the missile, then leave the area or take evasive action while the
missile guides itself to the target.
The AIM-9A, prototype of the Sidewinder, was first fired successfully in September 1953.
The initial production version, designated AIM-9B, entered the Air Force inventory in 1956
and was effective only at close range. It could not engage targets close to the ground,
nor did it have nighttime or head-on attack capability. These shortcomings were eliminated
on subsequent versions.
The AIM-9J, a conversion of the AIM-B and E models, has maneuvering capability for
dogfighting, and greater speed and range, giving it greater enhanced aerial combat
capability. Deliveries began in 1977 to equip the F-15
and other Sidewinder-compatible aircraft.
The AIM-9L added a more powerful solid-propellant rocket motor as well as tracking
maneuvering ability. An improved active optical fuze increased the missile's lethality and
resistance to electronic countermeasures. A conical scan seeker increased seeker
sensitivity and improved tracking stability. The L model was the first Sidewinder with the
ability to attack from all angles, including head-on. Production and delivery of the
AIM-9L began in 1976.
The AIM-9P, an improved version of the J model, has greater engagement boundaries,
enabling it to be launched farther from the target. The more maneuverable P model also
incorporated improved solid-state electronics that increased reliability and
maintainability. Deliveries began in 1978.
The AIM-9P-1 has an active optical target detector instead of the infrared influence
fuze; the AIM-9P-2 added a reduced-smoke motor. The most recently developed version, the
AIM-9P-3, combined both the active optical target detector and the reduced-smoke motor. It
also has added mechanical strengthening to the warhead as well as the guidance and control
section. The improved warhead uses new explosive material that is less sensitive to high
temperature and has a longer shelf life.
The AIM-9M, currently the only operational variant, has the all-aspect capability of the
L model, but provides all-around higher performance. The M model has improved defense
against infrared countermeasures, enhanced background discrimination capability, and a
reduced-smoke rocket motor. These modifications increase ability to locate and lock-on a
target and decrease the missile's chances for detection. Deliveries of the M model began
The AIM-9M-9 has expanded infrared counter measures detection circuitry. AIM-9X is a
future variant currently under developmen (look at "AIM-9X
Sidewinder tested in countermeasures environment
||Naval Weapons Center
||Hercules and Bermite Mk 36 Mod 71, 8 solid-propellant rocket
||9 ft 5 in
||2 ft 3/4 in
||Annular blast fragmentation warhead
||Solid-state, infrared homing system