What are Sonobuoys?

Sept. 28, 2023

The Indian Navy plans to equip the MQ-9B Sea Guardian medium altitude long-endurance (MALE) drones with sonobuoys.

About Sonobuoys:

  • Sonobuoys are small, expendable devices used in underwater acoustics and sonar systems to detect and analyze sound in the ocean, particularly for tracking submarines and other underwater objects.
  • Deployment:
    • Sonobuoys are deployed by dropping them into the ocean from aircraft or launching them from ships or submarines.
    • They sink to a predetermined depth and begin listening for acoustic signals, helping pin-point potential submarine threats.
    • Multiple sonobuoys can be deployed in a pattern to determine the exact location of a target.
  • There are three types of sonobuoys:
    • Passive Sonobuoys quietly listen for and record sounds without emitting any signals. It uses a hydrophone to listen for sound energy from a target.
    • Active Sonobuoys emit a sound pulse and analyze the return signals (echoes) to detect and locate targets. It uses a transducer to send an acoustic signal.
    • Special Purpose buoys provide information about the environment, such as water temperature, ambient noise level, etc.
  • Components: 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).
  • Other Applications: 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.

Key Facts about MQ-9B Sea Guardian:

  • It is a variant of the MQ-9 "Reaper", an unmanned aerial vehicle (UAV)capable of remotely controlled or autonomous flight operations.
  • These are high-altitude long-endurance drones armed with strike missiles which can take out enemy targets with high accuracy.
  • It was developed by General Atomics Aeronautical Systems (GA-ASI), primarily for the US Military.
  • The Indian Navy has been operating the MQ-9B Sea Guardian since 2020.
  • Features:
    • It can carry up to 5,670 kg and has a fuel capacity of 2,721 kg.
    • The drone can operate at over 40,000 feet.
    • The Predator also has a maximum endurance of 40 hours, making it useful for long-hour surveillance.
    • It is also capable of automatic take-offs and landings.
    • It can safely integrate into civil airspace, enabling joint forces and civil authorities to deliver real-time situational awareness anywhere in the maritime domain -- day or night.