The cylindrical bomb used Torpex ("torpedo explosive") to provide a longer explosive pulse for greater effect against underwater targets.

As well as providing experience with this type of technology, they also allowed the Royal Navy to practice against fast moving underwater targets.

Frost punched into Hunter's radio frequency just as the pilot was counting down to his first underwater "target."

She survived the war and in the early 1950s was modified to become a fast unarmed underwater target to train anti-submarine personnel.

The warhead is generally some form of aluminised explosive, because the sustained explosive pulse produced by the powdered aluminium is particularly destructive against underwater targets.

R4 was used as a fast underwater target at the Portland anti-submarine school until 1934, then sold on 26 May 1934 to Young, Sunderland.

Applies to vehicles designed to attack submarines and underwater targets.

R-10 was sold in 1929, while R-4 survived as a fast underwater target at Portland until 1934.

Tasks include the laying and maintenance of underwater targets, navigation marks and moorings.

Anti-submarine weapons target submarines and other underwater targets.