Avenger-class

Summary

Description

Avenger-class mine countermeasures ships were developed and built for the United States Navy, with a total of 14 ships constructed between 1987 to 1994. Their role is to clear mines from strategic waterways, which was underscored as crucial during conflicts such as the Iran-Iraq War and operations during the Gulf War. They were designed to find, classify, and destroy both moored and bottom mines. Ultimately, the class is being phased out and replaced by the Freedom and Independence-class littoral combat ships that rely on various manned and unmanned platforms for mine detection and neutralization.

These vessels have sonar and video systems, cable cutters, and mine detonating devices that can be operated remotely to engage in mine countermeasures. Additionally, they are equipped to conduct conventional sweeping as well. The mine countermeasure systems used on the Avenger-class include the AN/SLQ-48, from Alliant Techsystems (ATK), which finds and neutralizes mines while tethered to the ship by a significant cable. An alternative system developed by ATK and Raytheon, the EX116 Mod 0, utilizes similar technology for mine disposal with a longer tether.

The ships have reinforced hulls constructed from wood and coated with fiberglass, employing oak, Douglas fir, and Nootka Cypress for their strength and lightweight properties. This design choice provides durability against blasts as well as a reduced magnetic signature. Their sensor systems feature the AN/SQQ-32 sonar for minehunting, a submersible pod, and a surface-search radar, the AN/SPS-55. The propulsion system of the Avenger class includes four diesel engines with low magnetic and acoustic signatures, allowing a cruising speed of 14 knots. Precision movements are facilitated by Hansome electric motors and an Omnithruster hydrojet.

In terms of operational history, as of 2012, eight Avenger-class ships were in active duty, with four based in Sasebo, Japan, and another four in Manama, Bahrain, to respond to the threat of Iranian mining of the Strait of Hormuz. The ships rotated between ten crews for deployment. The international political climate, such as the tensions surrounding Iran's nuclear program, had a direct impact on the strategic deployment of these assets.

Avenger-class ships have been used in various operational roles and environments, as evidenced by USS Sentry and USS Kingfisher, USS Guardian, and USS Gladiator's active service records. Nevertheless, their lifecycle is limited, with decommissioning underway for ships like USS Champion, USS Scout, and others. The USS Guardian has a notable operational history, having been grounded on Tubbataha Reef in 2013 and ultimately scrapped due to the impossibility of salvaging the vessel intact.

Technical specifications