American mine countermeasures ship, introduced in 1987, displaces 1,312 tons. Key figures: displacement 1,312 tons, length 68 m, top speed 14 knots, crew 84, built 14. In service with 1 navy — United States (4).
| Subtype | Mine countermeasures vessel |
| Displacement | 1312 tons |
| Crew | 84 members |
| Width | 12.0 m (39.4 ft) |
| Length | 68.0 m (223.1 ft) |
| Propulsion | 4 × Waukesha Diesel engines (first two ships) or 4 × Isotta-Fraschini Diesel engines (600 hp (450 kW) ea.); 2 × 200 hp (150 kW) electric propulsion motors; 2 × shafts with controllable pitch propellers; 1 × 350 hp (260 kW) Omnithruster waterjet bow thruster |
| Maximum speed | 14 knots |
The United States Navy developed the Avenger-class mine countermeasures ships in the early 1980s. Peterson Shipbuilders and Marinette Marine constructed 14 vessels between 1987 and 1994 to replace the Ability-class minesweeper. The class is designed to find, classify, and destroy moored and bottom mines.
The hulls are constructed of oak, Douglas fir, and Nootka Cypress with an external fiberglass coating. This wooden construction allows the hull to withstand nearby explosions and maintains a low magnetic signature. For mine detection, the ships utilize the AN/SQQ-32 advanced minehunting sonar, which consists of search and classification sonars fitted in a submersible pod towed under the ship. Neutralization is performed by remotely operated vehicles, such as the AN/SLQ-48 and EX116 Mod 0. These tethered units use high-frequency sonar, low-light television, cable cutters, and explosive charges to dispose of mines. Propulsion consists of four diesel engines—either Waukesha-Pearce or Isotta-Fraschini units—designed for low magnetic and acoustic signatures. The ships use electric motors for stationkeeping and an Omnithruster hydrojet for precision maneuvering.
Operational history includes mine countermeasures in the Persian Gulf during the Iran-Iraq War and Operations Desert Shield and Desert Storm. By 2012, eight vessels were forward-based in Sasebo, Japan, and Manama, Bahrain. Four additional units were deployed to Bahrain in 2012 to monitor the Strait of Hormuz. One vessel, USS Guardian, was lost in 2013 following a grounding on Tubbataha Reef. The United States Navy began decommissioning the class in 2014, with several units retired in 2020. The Freedom and Independence-class littoral combat ships are designated to replace the class. Current active units are scheduled for decommissioning through 2027.
IMF PortWatch data published on GMN's Strait of Hormuz tracker shows commercial ship transits averaging 3.17 a day over 1-6 September 2026, against 85.5 a day in 2025; other counters read higher, but every independent count is a small fraction of the pre-war norm.
The United States decommissioned its four Bahrain-based Avenger-class mine hunters in September 2025 and shipped the hulls home in January 2026. When Iran began mining the Strait of Hormuz two months later, according to CENTCOM, the Navy had to sail two of its last four minesweepers from Japan.