55.6.1 Mission

Mine warfare ships include both minelayers and minesweepers (or mine countermeasures ships). The mission of mine countermeasure ships is to clear areas of enemy mines so that friendly ships may have safe passage. This is accomplished by hunting, locating, and neutralizing individual mines or by sweeping minefields.

Defensive minefields are typically laid off harbors and ports to deny an enemy access. They can be employed, for example, to discourage or hinder an amphibious landing. Purpose-built minelayers come in many different sizes, but can be characterized by a stowage system, and rails for moving the mines and dropping them off the side or stern of the ship. In fact, however, nearly any surface ship (or craft) can be pressed into ad hoc service to lay mines. Once a defensive minefield is laid, it must be periodically replenished.

In contrast, offensive minefields are laid to prevent an enemy the use of their own waters. This requires the minelayer to penetrate waters that the enemy controls. Today, in the U.S., submarines and aircraft lay offensive mines. Because the navies of the world possess few dedicated minelayers, minesweepers will be the primary subject of this section.

Specially equipped helicopters also have a role in mine countermeasures. The helicopter has a higher sweep rate against certain mines than a ship, but a shorter mission time. Although not discussed in this chapter, the mine countermeasure helicopter supplements and complements its ship counterparts.

55.6.2 Design Drivers

Mines have...