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How do infrared heat-seeking missiles find aircraft targets?
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rocket and missile system
U.S. soldiers firing an FGM-148 Javelin antitank guided missile during training in Grafenwöhr, Ger., 2006.
Infrared heat-seeking missiles utilize passive guidance systems to locate and track aircraft targets. Unlike command-guided systems that rely on external signals, these missiles "lock" onto the infrared emissions generated by the target, specifically targeting the heat produced by jet engine exhausts.1
The process typically involves the following:
- Target Acquisition: The missile’s seeker head detects the heat signature of the aircraft. In many systems, a human operator must identify and lock onto the target before launch, often confirmed by an audible tone in the operator's headset.1
- Passive Homing: Once locked, the missile homes in on the infrared radiation without emitting its own energy or receiving external commands.1
- Advanced Imaging: More sophisticated systems use imaging infrared technology, which functions similarly to the human eye. These missiles can "see" and memorize a visual or infrared image of the target, using onboard computers to calculate the optimal intercept trajectory.1
Early examples of this technology include the AIM-9 Sidewinder, while later developments led to portable, shoulder-fired systems like the Stinger and Redeye.1