SINKEX or Sink Exercise is a US military term for the test of a weapons system usually involving a torpedo

Torpedo

The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

 or missile

Missile

Though a missile may be any thrown or launched object, it colloquially almost always refers to a self-propelled guided weapon system.-Etymology:The word missile comes from the Latin verb mittere, meaning "to send"...

 attack of an unmanned target ship

Target ship

A target ship is a vessel — typically an obsolete or captured warship — used for naval gunnery practice or for weapons testing.-Rationale: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...

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The US Navy sometimes refers to this type of exercise as a HULKEX (Hulk

Hulk (ship)

A hulk is a ship that is afloat, but incapable of going to sea. Although sometimes used to describe a ship that has been launched but not completed, the term most often refers to an old ship that has had its rigging or internal equipment removed, retaining only its flotational qualities...

 + Exercise). Also, the US Navy uses SINKEX to train its sailors on the usage of modern-day weapons.

This technique is used to dispose of decommissioned warships. The US Navy performs SINKEXs north of Kauai, Hawaii, in the Pacific Ocean

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

 off the coast of California, and near Puerto Rico

Puerto Rico

Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...

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