pinger

British  

/ ˈpɪŋə /

noun

1. a device that makes a pinging sound, esp one that can be preset to ring at a particular time

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Example Sentences

Usually, an underwater vehicle will have a device called a pinger that can correspond with the surface and make it easier to locate, Dzieciuch said.

From Seattle Times

A high-frequency acoustic pinger would be even more efficient, as this would provide directional accuracy to home onto a distressed submersible.

From Scientific American

Many underwater vehicles are fitted with an acoustic device, often called a pinger, which emits sounds that can be detected underwater by rescuers.

From Seattle Times

When planes go down in the ocean, a pinger attached to the black box sends a signal that sounds like a grandfather clock ticking for about 30 days before its battery dies.

From Washington Post

Search teams are using an underwater drone, as well as underwater "pinger locators", to try to pick up the sonar signals from the cockpit recorders.

From BBC