Naval mine ship, HMHS "Britannic", which was the sister ship of the RMS "Titanic." During World War II, the U-boat fleet, which dominated much of the battle of the Atlantic, was small at the beginning of the war and much of the early action by German forces involved mining convoy routes and ports around Britain. German submarines also operated in the Mediterranean Sea, in the Caribbean Sea, and along the U.S. coast. Initially, contact mines (requiring a ship to physically strike a mine to detonate it) were employed, usually tethered at the end of a cable just below the surface of the
Type 679 training ship division of Jiangnan Shipyard. The ship is designed to be crewed by 170 sailors and 30 instructors are also assigned to the ship. The ship has a large hospital on board to accommodate cadet classes. Originally, the ship could house 170 cadets at any one time in addition to the 170 crew and 30 instructors; this number was increased to 200 when the number of chart rooms (originally there were three) was reduced, as a result of the adoption of electronic charts during later upgrades. When the ship first entered service in 1987, it was the first ship in the