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How does a helicopter use a dunked sonar sensor to detect submarines?
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undersea exploration
Learn about the pioneering life and work of American oceanographer and explorer Sylvia Earle.
To detect submarines, a helicopter utilizes a "dunked" or "dipping" sonar sensor, which is a device suspended from the aircraft by a cable and lowered into the water.123
Once submerged, the sensor operates using acoustic techniques to identify underwater targets through two primary methods:
- Active Sonar: The sensor acts as an acoustic projector, emitting sound waves that travel through the water. If these waves strike a submarine, they reflect back to the sensor, allowing the system to determine the target's range, bearing, and relative motion.4
- Passive Sonar: The sensor acts as a receiver, listening for and analyzing noise generated by the submarine, such as propeller sounds or other mechanical signatures.24
Because sound energy in water is subject to attenuation and distortion from temperature layers or extraneous noise, these sensors provide a critical mobile capability for tracking targets in areas where fixed sensors are unavailable.12