Aggressive class minesweeper

The "Aggressive" class minesweepers are a class of US-built minesweepers. They are designated as "MSO" (Mine Sweeper Ocean), distinguishing them from the smaller coastal MSCs and inshore MSIs. Minesweeping, or the disposal of naval mines by these vessels is performed in different ways:
*Sweeping proper, with an underwater cable cutting the mooring cables of floating mines, the mines coming to the surface are then destroyed by gunfire
*Acoustic sweeping, with a towed device producing noise to trigger acoustic mines
*Magnetic sweeping, with a towed device producing a magnetic field to trigger magnetic minesTo protect them against magnetic mines, the hull of the ship is made of wood.

Besides the US Navy, this class of vessels has also been used by the Belgian Navy and the Norwegian Navy, among others.

Construction and disposition

Of the 53 constructed for the United States Navy, 10 were built at Higgins Corp., New Orleans, Louisiana, 9 at J. M. Martinac Shipbuilding Corp., Tacoma, Washington, 8 at Wilmington Boat Works Inc., Wilmington, California, 6 at Luders Marine Construction Co. of Stamford, Connecticut, 4 at Broward Marine Inc, Fort Lauderdale, Florida, 4 at Martinolich Shipbuilding Co., San Diego, California, 3 at Burger Boat Company, Manitowoc, Wisconsin, 3 at Colberg Boat Works, Stockton, California, 2 at Fulton Shipyard, Antioch, California, 2 at Norfolk Naval Shipyard and 2 at Seattle Shipbuilding and Drydocking Co., Seattle, Washington.

33 of the class were decommissioned before the mid-1970s. Four ex-USN ships were sold to the Republic of China Navy 1994 and re-classed as Yung Yang class minesweepers. They were still in active service as of 2002. USS|Implicit|MSO-455 was decommissioned September 30, 1994 in Tacoma, Washington and was the last Aggressive class minesweeper in US Navy active service.

General development of minesweeping

Minesweepers have been in operation since World War I and originally involved a simple metal detector, which soldiers used to locate mines. This practice was dangerous not only from the risk of missing and detonating a mine, but also because the enemy would be making the task harder for the sweepers by keeping them under constant, heavy fire. Minesweepers were greatly admired by their peers because of their bravery.

Aggressive class minesweepers used AN/SQQ-14 mine hunting sonar to locate moored or bottom mines. They used electromagnetic cables to set off mines or other cables to cut their mooring lines, and various magnetic and acoustical devices to set off mines. Toward the end of their use, the class also employed remote submersibles like Super Sea Rover to locate mines.

Today, active minesweepers or minehunters are frequently used. The Royal Navy of the United Kingdom uses small submarines that are controlled by wireless operators onboard the several minesweeping frigates that it possesses. Sweden produce a robotic Self-propelled Acoustic/Magnetic Minesweeper (SAM), which proved its worth during Operation Desert Storm, when it was successfully used for minesweeping by the US Navy. SAMs are currently in service with the Swedish Navy, the Japanese Navy, the Royal Navy and the US Navy, though not necessarily aboard Aggressive class minesweepers.

Units

External links

* [http://www.fas.org/man/dod-101/sys/ship/mso-422.htm FAS - MSO-422 class]
* [http://www.globalsecurity.org/military/systems/ship/mso-422.htm GlobalSecurity - MSO-422 class]
* [http://www.geocities.com/Pentagon/Bunker/2170/102msos.html 102 MSOs]