A target ship is commonly a captured enemy, outdated or obsolete ship that is towed out to sea and sunk by naval and air forces or demolition squads. The target ship provides a realistic method of training and demonstrates the efficiency of a shot placement for the crew. The ship can be stationary, or maneuvered by remote control to simulate actual battle conditions by manipulating the target ship through evasive measures as it is being attacked. Preparation, such as removing toxic materials and fuel from the ship, must be completed prior to sinking the vessel to provide a safe structure for undersea aquatic life, military divers and future visitors.
Many military forces around the world hone their targeting and combat skills by shelling and bombing a target ship. The target ship will often be a captured enemy ship in order to more accurately portray actual battle conditions. This also instills pride and confidence in the military forces by allowing them to see an enemy vessel destroyed using their equipment. Experimental weapons are often used to test the effectiveness against an actual enemy ship or submarine. Some navy units will donate obsolete vessels to be used as a target ship, thereby rendering the vessel unsearchable by enemy divers and explorers.
While many obsolete military ships are donated and sunk to be used as artificial reefs, this is typically not advised of a target ship due to the possibility of unexploded ordinance. It is common for several rounds of ammunition, bombs and rockets to strike the ship while not exploding. The slightest bump or disturbance from a diver or even the turbulence from a diver's fin could result in a catastrophic explosion. This is why most target vessels are towed out to very deep waters to be sunk.
Although they are usually not suitable for diving exploration, the ships remain habitat for marine life, so toxic materials cannot go down with the vessels. The target ship is prepared by cleaning all fuel tanks, removing all insulating materials such as asbestos and munitions prior to targeting. All materials thought to be a potential threat to the environment or marine life are removed from the ship. In the case of an ex-military vessel, the guns and much of the targeting and navigation instrumentation are removed to eliminate the threat of an enemy receiving secret information and technology. For military target ships, all identification numbers and signage are removed to preserve and respect the memory of their military history and combat tours.