U.S. Navy Expands Unmanned Mine Hunting After Retiring Avenger Ships Amid New Hormuz Mine Threats.

The U.S. Navy is expanding its unmanned mine countermeasures capabilities through a $53.9 million contract awarded to Advanced Acoustic Concepts (AAC), a subsidiary of French defense group Thales. The agreement covers two Remote Mine Hunting (RMH) modules designed to detect and classify underwater mines while keeping crewed ships outside dangerous waters. The investment comes as Washington replaces traditional minesweepers with unmanned systems amid renewed threats to strategic maritime routes.

Minecountermeasure Unmanned Surface Vehicle (MCM USV) is recovered onboard USS Manchester (LCS 14) during Unmanned Influence Sweep System Initial Operational Test & Evaluation June 2021 (Picture source: US Navy)

The contract includes engineering support and options that could increase its total value to $196.2 million. The initial order remains limited to two modules, but additional acquisitions could expand the fleet's capacity to survey mine-threatened waters. This comes as the Navy transfers responsibilities previously performed by dedicated mine countermeasures ships to Littoral Combat Ships (LCS) equipped with remotely operated vehicles.

According to a statement published by Thales on November 2, 2026, the new equipment combines synthetic aperture sonar with automated target classification and mission management software. The announcement follows the retirement of four Avenger-class mine countermeasures ships stationed in Bahrain in September 2025. Their replacement includes Independence-class LCS vessels equipped with unmanned mine warfare systems, a transition that has become particularly relevant following the disruption of maritime traffic through the Strait of Hormuz during the 2026 conflict with Iran.

Advanced Sonar Technology to Identify Underwater Mines

The RMH solution incorporates a multiview towed Synthetic Aperture Sonar (SAS), designed to produce high-resolution acoustic images of objects resting on or positioned above the seabed. Unlike conventional side-scan sonar, synthetic aperture processing combines successive acoustic measurements as the sensor moves, improving image resolution and allowing operators to distinguish potential mines from rocks, wreckage and other underwater objects.

Thales already manufactures the SAMDIS family of multiview synthetic aperture sonars, whose technology illustrates this approach. SAMDIS uses three independent viewing angles of +30, 0 and -30 degrees to examine underwater contacts during a single survey pass. Its onboard processing also generates full-resolution imagery without requiring subsequent processing ashore. These characteristics reduce the need for repeated passes over suspicious objects, although Thales has not confirmed the precise sonar variant incorporated into the newly contracted American modules.

The second component consists of artificial intelligence-assisted Automatic Target Recognition (ATR) software, which processes sonar returns to detect, classify and map mine-like contacts. By reducing false alarms, the software can limit the number of objects requiring additional inspection and shorten the interval between detection and identification. Thales has not released the new system's detection range, operating depth, survey speed or classification accuracy, preventing a direct performance comparison with existing U.S. Navy equipment.

The RMH modules will support the Navy's broader unmanned mine countermeasures architecture, which already includes the 38.5-foot (11.7-meter) Mine Countermeasures Unmanned Surface Vehicle (MCM USV). This craft uses a modular payload bay that can be reconfigured for mine-hunting or minesweeping missions. Existing configurations employ the AN/AQS-20 sonar, while separate systems provide mine neutralization. The Thales contract focuses on detection and classification, with further integration of remote neutralization capabilities envisaged for the future.

Strait of Hormuz Mine Threat Exposes Operational Requirements

The operational importance of these technologies became apparent during the 2026 confrontation with Iran. On April 11, U.S. Central Command announced that American forces had begun establishing conditions for mine clearance in the Strait of Hormuz. The guided-missile destroyers USS Frank E. Petersen Jr. (DDG 121) and USS Michael Murphy (DDG 112) entered the Persian Gulf as part of operations intended to restore safe maritime passage after Iranian mine-laying activities. CENTCOM also announced that underwater drones would participate in subsequent clearance efforts.

The scale of the disruption illustrates why mine countermeasures remain essential even for technologically advanced naval forces. On August 25, Reuters reported that oil shipments through Hormuz had fallen to approximately 5 million barrels per day, compared with more than 20 million before the conflict. Although missile and drone attacks also contributed to the disruption, the mine threat complicated efforts to reassure commercial operators. The same month, American forces struck Iranian launchers reportedly prepared to deploy naval mines into the waterway, demonstrating the continued risk of renewed mining.

The consequences extend beyond the Persian Gulf, particularly in the Indo-Pacific, where the U.S. Navy is preparing for mine warfare operations alongside Japan and South Korea. In June 2025, the U.S. 7th Fleet established Task Force 77 in Sasebo, Japan, to coordinate mine countermeasures across the region. More recently, American and South Korean forces conducted joint mine clearance exercises near Pohang in April 2026, simulating the opening of a safe passage through a mined area. Such capabilities would be essential during a conflict around the Korean Peninsula or Taiwan, where naval mines could obstruct access to ports, delay amphibious operations, and restrict the movement of reinforcements. The Thales contract supports this broader transition toward unmanned mine hunting, although its effectiveness will depend on integrating the new sensors with operational platforms and mine neutralization systems.

Written By Erwan Halna du Fretay - Defense Analyst, Army Recognition Group
Erwan Halna du Fretay holds a Master’s degree in International Relations and has experience studying conflicts and global arms transfers. His research interests include security and strategic studies, particularly the dynamics of the defense industry, the evolution of military technologies, and the strategic transformation of armed forces.

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