Sonobuoys : For Undersea Domain Awareness
India and the U.S. recently announced cooperation on the co-production of U.S. sonobuoys for Undersea Domain Awareness (UDA) for the Indian Navy, a high-end technology that allows tracking submarines in the deep seas and oceans.
- Sonobuoys are expendable, electro-mechanical acoustic sensors that relay underwater sounds emitted from ships and submarines.
- They help in the detection, classification, and prosecution of adversarial ships and submarines.
- A naval helicopter or fixed-wing aircraft generally drops sonobuoys in a pattern.
- They are dropped in canisters and are deployed automatically upon impact with water.
- An inflatable system with a radio transmitter remains on the surface for communication with the ship or aircraft tracking it while sensors descend below the surface to a predetermined depth.
- It then relays acoustic information back to those monitoring them.
- A group of sonobuoys deployed in a pattern can find out the exact location of the submarine, which then can be tracked by other systems.
- Some sonobuoys are designed to be deployed in passive mode and some in active mode.
- Active sonobuoys emit sound energy and receive the echo, based on which they transmit information back to the aircraft.
- Passive sonobuoys, on the other hand, only listen for sounds coming from ships or submarines. They then transmit the sound back to the aircraft.
- There are also Special Purpose buoys that provide information about the environment, such as water temperature, ambient noise level, etc.
- A typical sonobuoy consists of a cylindrical or spherical buoyant housing, sensors for detecting acoustic signals, a battery or power source, and a radio transmitter or other communication system to relay data to the host platform (e.g., aircraft or ship).
- In addition to anti-submarine warfare, they are used for scientific research and environmental studies, including studying the behavior of whales and other marine creatures.
