Sinking exercise

A target ship is a vessel — typically an obsolete or captured warship — used as a seaborne target for naval gunnery practice or for weapons testing. Targets may be used with the intention of testing effectiveness of specific types of ammunition; or the target ship may be used for an extended period of routine target practice with specialized non-explosive ammunition. The potential consequences of a drifting wreck require careful preparation of the target ship to prevent pollution, or a floating or submerged collision risk for maritime navigation.

Sinking redundant warships is an effective way of testing new weapons and warships in as realistic a manner as possible. Whilst practice torpedoes are fired fairly frequently, they behave differently from warshots.

In order to meet environmental, health, and safety standards, ships now have to be thoroughly cleaned so that all dangerous material and potential contaminants (such as asbestos, refrigerants etc.) are removed. In the event of the vessel becoming an artificial reef, escape exits also have to be created in the vessel, should divers encounter problems. It is now also common practice to remove pennant numbers and sink the warships anonymously, as a mark of respect to those who sailed in them.

In September 1819, the French engineer and Army artillery officer Henri-Joseph Paixhans wrote to the Ministry of the Navy to propose a fusing system to fire explosive shells at wooden warships, instead of the usual, solid round shots that were then in general naval use. A commission studied the matter, and decided to build two Paixhans howitzers for trial purposes in 1822.

In 1824, the 80-gun ship of the line Pacificateur, made redundant by the Bourbon Restoration, was condemned. She was a Bucentaure-class two-decker of the same type as the French flagship of the Battle of Trafalgar. The two prototypes were fired at her with devastating effect. This led to the adoption of the Paixhans gun in 1827. They were used to great effect at the Battle of San Juan de Ulua, to the interest of British and US observers, who announced the demise of wooden warships and the era of the ironclad.

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