Unmanned submarines, which are known as Autonomous Underwater Vehicles (AUV), were crucial in finding the black box recorders from Air France Flight 447 after it crashed into the Atlantic Ocean in 2009, killing all 228 people onboard.
Investigators are currently using an underwater drone and a black box locator attached to the Australian Defence Vessel (ADV) Ocean Shield, a large Australian Royal Navy ship that is being used in the search. Attaching these devices to the ship enables real-time data transmission to the surface and a continuous power supply from the ship to the devices, however this is a very slow way to search for wreckage.
An advantage of using AUV unmanned robot submarines is that they can travel much deeper underwater than regular submarines and can stay underwater for between 20 to 24 hours."
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