Description
The MK 48 heavyweight torpedo is used by all classes of submarines as their anti-submarine warfare (ASW) and anti-surface warfare (ASuW) weapon.

The MK 48 torpedo is a heavyweight acoustic-homing torpedo with sophisticated sonar, all-digital guidance-and-control systems, digital fusing systems, and propulsion improvements. Its digital guidance system allows for repeated upgrades to counter evolving threats through software upgrades. The last MK 48 MOD 6 production torpedo was delivered in 1996. Since then, the Navy has provided discrete improvements to MK 48 MOD 6 via upgrade kits to the torpedo's guidance and control and propulsion systems. The MK 48 MOD 6 torpedo reached Initial Operational Capability (IOC) in 1997 and continues to receive software upgrades.

The latest version of the MK 48 is the MOD 7, which is optimized for both traditional and emerging missions. The MK 48 MOD 7 torpedo is the result of a Joint Development Program with the Royal Australian Navy and reached IOC in 2006. The MK 48 MOD 7 hardware upgrade has enabled further software improvements to the MK 48 that provide increased capability in the most challenging scenarios. 

General Characteristics, MK 48 
Primary Function: Heavyweight Torpedo
Contractor: Lockheed Martin
Propulsion: Liquid propellant 
Diameter: 21 inches
Weight: 3,744 pounds
Warhead: 650 pounds, high-explosive