Knockout blow: torpedoes primed to deliver a heavyweight punch

The last decade has not been the easiest of times for many of those companies that have traditionally been engaged in the engineering and manufacture of heavyweight torpedoes.

Whereas 10 years ago there were at least six companies in the western hemisphere undertaking the development, manufacture and marketing of complex 533 mm-diameter underwater guided weapons, reduced domestic development funding and declining international demand means that today there appear to be only three enterprises - one in the United States and two in Europe - that can still claim heavyweight torpedo development and production as a core business stream. That is not to say, however, that others are not still active at a certain level, for example providing long-term support and post-design services.

To the east, there is a somewhat different situation as existing and emergent naval powers identify the maintenance and/or development of an indigenous heavyweight torpedo programme as an important sovereign military capability. Russia, despite the budget difficulties encountered in the post-Soviet era, has retained a large underwater weapons scientific and industrial base and continues an active programme of heavyweight torpedo development. Meanwhile, China and South Korea have locally developed heavyweight weapons that build on overseas design pedigree, while India is starting trials this year of an indigenous weapon.

Working as a 'Team Torpedo' collective with Raytheon Integrated Defense Systems (manufacturing, design engineering and support services) and the Naval Undersea Warfare Center (NUWC) at Portsmouth, Rhode Island (systems engineering and test), the US Navy's (USN's) Undersea Weapons Program Office (PMS 404) has embarked on a 'spiral' programme of hardware and software upgrades intended to evolve the Mk 48 ADCAP (Advanced Capability) heavyweight torpedo.

Derived from the earlier Mk 48 Mod 4, the original Mod 5 ADCAP entered service in the late 1980s and introduced digital sonar, signal processing and guidance and control while retaining the proven dynamics and Otto Fuel II propulsion of its progenitor. The last new ADCAP torpedo was delivered in 1996.

The successor Mk 48 Mod 6 torpedo combines two enhancements: one in guidance and control, the other in the torpedo propulsion unit. The guidance and control modification improves the acoustic receiver, replaces the guidance-and-control set with updated technology, increases memory and improves processor throughput to handle expanded software demands. The propulsion system modification provides a tactically significant reduction in torpedo radiated-noise signatures.

The Mod 6 is also the first torpedo that can utilise a Torpedo Downloader System to enable rapid software updates to embarked weapons, meaning that the submarine deploys with the most up-to-date software variant. Initial operational capability was attained in 1997.

The engineering, development, manufacturing and support of the next evolution of the ADCAP line, embodied in the Mk 48 Mod 7 programme, is being pursued in collaboration with Australia under a 10-year Armaments Cooperative Project (ACP) signed in 2003. The Royal Australian Navy (RAN) is acquiring the Mk 48 Mod 7 for its six Collins-class boats as a successor to the Mk 48 Mod 4 under Project Sea 1429 Phase 2.

Image: The Chinese Yu-6 heavyweight torpedo, reported to have entered service with the People's Liberation Army Navy in 2005, is reputed to have its origins in a US Mk 48 weapon recovered from the sea and then reverse-engineered. (Via Chinese Internet) 501 of 4,428 words