Mark 6 exploder

The Mark 6 exploder was a United States Navy torpedo exploder developed in the 1920s. It was the standard exploder of the Navy's Mark 14 torpedo.

Early torpedoes used contact exploders. A typical exploder had a firing pin that stuck out from the warhead and was restrained by a transverse shear pin. The torpedo would hit the target with enough energy to break the shear pin and allow the firing pin to strike a percussion cap that ultimately detonated the warhead. An arming impeller was an additional safety device: the firing pin could not move until the torpedo had traveled a preset distance.

Just before World War I, the Bureau of Ordnance (commonly called BuOrd) started developing an inertial exploder. The result was the Mark 3 exploder.

Warships employed defenses against torpedoes. A new technology, torpedo blisters, appeared on capital ships. The torpedo would explode against the blister but do little damage to the hull. Torpedo blisters were tested on two battleships, the decommissioned South Carolina and the unfinished Washington; the conclusion was the Mark 10 torpedo, with its contact exploder, could not disable a major warship. Torpedoes would need to explode underneath a capital ship, where there were no blisters or other armor. The Mark 14 torpedo was designed at the Newport Torpedo Station (NTS), Newport, to replace the Mark 10, which had been in service since World War I. Its fairly small 643 lb (292 kg) warhead required it to explode beneath the keel where there was no armor.

This led to the development of a magnetic influence feature, similar to the British Duplex and German models, all inspired by German magnetic mines of World War I. The Mark 6 was intended to fire the warhead beneath the ship, creating a huge gas bubble which would cause the keel to fail catastrophically.

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