Tag Archives: Sidewinder Missile

AIM-9 Sidewinder Missile

One of the oldest, yet most effective short range weapons in air to air combat is the AIM-9 Sidewinder Missile.

After World War II, the most popular missile guidance system was radar. This was expensive to build and required manned operation to help guide the missile to its intended target. Then in 1947, a Naval physicist named Bill McLean began researching and developing a new type of system that would not utilize radar. Instead, it would search for the infrared signature of the aircraft using infrared (heat seeking) technology. This was not only more precise than radar but weighed much less as well.

Initially, the Sidewinder guidance system was equipped with vacuum tubes that were used to form the guidance computer, but with the advent of semiconductors, vacuum tubes were replaced with the actual program embedded within the semiconductor chip.

AIM Sidewinder Missile
A U.S. Navy McDonnell Douglas F/A-18A Hornet firing an AIM-9R Sidewinder missile at China Lake, California (USA), 5 April 1991. USAF Public Domain.

The AIM-9 weighs 188 lbs and is 9 feet, 11 inches long and uses a WDU-17/B warhead.

In general, a missile of this type requires nine major components:

  • The rocket motor, which provides the thrust to propel the missile through the air
  • The rear stabilizing wings, which provide the necessary lift to keep the missile aloft
  • The seeker, which sees the infrared light from the target
  • The guidance control electronics, which process the information from the seeker and calculate the proper course for the missile
  • The control actuation section, which adjusts flight fins near the nose of the missile based on instructions from the guidance electronics
  • The flight fins themselves, which steer the missiles through the air — just like the flaps on an airplane wing, the moving flight fins generate drag (increase wind resistance) on one side of the missile, causing it to turn in that direction.
  • The warhead, the explosive device that actually destroys the enemy aircraft
  • A fuze system that sets the warhead off when the missile reaches the target
  • A battery to provide power to the onboard electronics

Needless to say, the Sidewinder missile has certainly shown its capability as it has been in existence  from 1956 to present day.