Page 9: of Marine Technology Magazine (March 2026)

a decade ago. At the same time, the lines them dif? cult to detect in the acoustically no longer limited to specialized military separating mines, torpedoes, and UUVs cluttered environments typical of busy units, and may increasingly enter the are blurring as these systems increasingly ports, and they can in? ltrate harbors au- toolkit of both state and non-state actors.

converge in both capabilities and mission tonomously using advanced navigation As these risks grow, coastal installations sets. For ports and naval facilities, where systems. And the growing affordability are increasingly adopting layered secu- ships, logistics infrastructure, and critical and accessibility of UUV technologies rity approaches combining deterrence, undersea assets are concentrated in con- means underwater strike capabilities are surveillance, and response.

? ned areas, this convergence introduces new vulnerabilities. Even as many ports have implemented robust security mea- sures against air and surface threats, and cybersecurity has received increasing at- tention in recent years, the underwater environment remains comparatively dif- ? cult to monitor and defend.

A Subsea Threat Matrix

Ports and naval bases face a diverse set of potential underwater threats, each with distinct operational characteristics and detection challenges. Combat divers represent the most traditional of these.

Operating either with open-circuit scuba equipment or closed-circuit rebreath- ers, divers can deploy from outside the harbor perimeter, approach a target co- vertly, and emplace limpet mines or other explosive devices on hulls, piers, or subsea infrastructure.

Diver propulsion vehicles (DPVs) are small battery-powered scooters that allow divers to travel faster and with less fatigue than swimming alone. DPVs extend the operational range of combat swimmers and support covert reconnaissance, mine placement, or infrastructure sabotage. A larger and more capable variant of this concept is the swimmer delivery vehicle (SDV). SDVs are small submersibles en- abling special operations forces to covert- ly in? ltrate defended areas from stand-off range, often launching from submarines or surface vessels operating well outside a harbor’s surveillance perimeter.

Increasingly, however, the most conse- quential threat may come from UUVs.

Advances in autonomy, navigation, and battery technology have enabled relative- ly compact UUVs to operate with consid- erable range and precision. These vehi- cles can carry sensors for reconnaissance or payloads designed to damage ships or infrastructure, all without risking human life. Their low acoustic signatures make www.marinetechnologynews.com 9

MTR #3 (1-17).indd 9 MTR #3 (1-17).indd 9 3/30/2026 1:12:12 PM3/30/2026 1:12:12 PM