Science of Conflict

The torpedo

Not all torpedoes are designed to home in on the target and explode on impact. Some are designed to explode several metres below the hull of a ship in order to cause maximum damage.


On detonation, triggered by recognition of the ship's magnetic signature, a spherical gas bubble forms. A high pressure shock wave moves through the water and applies a huge force to the hull crushing it and lifting it out of the water. After 0.5 seconds the gas bubble shrinks, under pressure, causing the ship to sag and fracture even more. One second after the explosion the pressure bubble expands violently forming a high velocity water jet that moves through the hull of the ship destroying its deck.
Actual footage of an MK-48 is shown on the right. Modern day torpedoes do not operate by slamming into the hull of a ship and exploding. Ships are made of many watertight compartment which can be sealed off when damaged and become flooded. The ship can keep floating and even be repaired. At the very least the ship will take longer to sink and allow for its personal to be evacuated. By exploding the warhead under the ship the hull is split in two and the ship immediately sinks.


An Australian Collins Class submarine is pictured on the right loading a torpedo. Image and information from the Australian defence web page. The MK-48 is designed to combat fast, deep-diving nuclear submarines and high performance surface ships. The MK-48 has been in service in the U.S. Navy since 1972. MK-48 ADCAP entered service in 1988.



The MK-48 and MK-48 ADCAP torpedoes are part of the Collins Class submarine's arsenal. They can operate with or without wire guidance and use active and/or passive homing. When launched they execute programmed target search, acquisition and attack procedures. Both can conduct multiple re-attacks if they miss the target.
Why are modern torpedos, such as the Mk-48 more effective against ships than older torpedos that detonated when colliding with the hull of the ship?