DCM is the Weapons Interface Equipment which has been in service with various classes of Royal Navy submarines since the early 1980s. Located in the submarine fore-ends, this equipment was originally an integral part of the DCB Fire Control System which included Fire Control Consoles and Computers. The Fire Control Consoles and Computers were eventually superseded by SMCS, but the fore ends Weapons Interface Equipment was retained in service and re-designated DCM.

DCM comprises various cabinets which accommodate modules to provide weapon power, control/interface and weapon simulation. Cabinets are configured for either Port or Starboard tubes, module sets within the cabinets being dedicated to their respective tube and selected as required by the weapon type loaded. Interfacing with new weapon variants is also supported this way through the introduction of new module sets.

Since the middle to late 1980s, weapon control/interface modules have incorporated increasingly more powerful processor technology which has made possible the development of modules capable of supporting more than one weapon type. This and the need to support mixed weapon outloads resulted in the development of a ‘multi-weapon’ capable module set. The first ‘common module set’ entered service during the late 1980s and supported the Spearfish torpedo and RNSH missile. By the early 1990s, Ultra and Lockheed Martin were successful in winning the MoD contract to introduce Tomahawk into Royal Navy submarines and this resulted in the further evolution of the ‘common module’ to the current ‘Tri-Weapon Module’ which supports Spearfish, RNSH and Tomahawk.