USN Legacy MCM Programs

Mine clearance was the US Navy’s glaring weak point during Operation Desert Storm in Iraq – 25 years ago. The Navy’s final MH-53E helicopters were then equipped with Northrop Grumman’s AN/AQS-14, but Raytheon’s AN/AQS-20 was to replace this system for front-line service (yes, the AQS-20 was expected to enter production more than 25 years ago). The AQS-20 was to be a far superior system, both in terms of additional abilities and increased surveillance volume and accuracy.

Instead, as the AQS-20 languished in development, Northrop Grumman’s AN/AQS-24 Mine Hunting and Identification system was developed in support of a US Navy Urgent Operational Need (UON), to improve the rapid detection and localization of volume sea mines. The AQS-24 is comprised of acoustic sensors housed in an underwater towed body, and the AQS-24B upgrade kit seems to have been developed quickly, based on Northrop’s legacy AQS-14. According to the Navy, initial AQS-24 RDT&E funding was completed in FY14, with immediate production funded from FY14-FY16.

Littoral Combat Ship (LCS): The Future & End of USN MCM

Regarding the ships carrying and supporting MCM systems, following two decades of delays the US Navy’s Littoral Combat Ship (LCS) program had finally solidified by the early 2020s – just as hull construction was ending. The LCS has been controversial from its beginnings, due to cost growth, design and construction issues with the lead ships built to each design, concerns over the ships’ survivability (i.e., ability to withstand battle damage), concerns over whether the ships are sufficiently armed and would be able to perform their stated missions effectively, and concerns over the development and testing of the ships’ modular mission packages.

In June 2021, the keel laying ceremony took place at Marinette Marine in Marinette, WI, for the last Littoral Combat Ship of the monohull Freedom class, the future USS Cleveland (LCS-31). Thus, even with the unanticipated early retirements of some LCSs, the US Navy will operate a large fleet of LCSs for another decade or more – whether they like them or not. And bizarrely, the equally unloved LCS sonar and ASW (Anti-Submarine Warfare) systems will soon form the backbone of the US Navy’s modern Mine Countermeasures (MCM) capability.

In April 2023, Fincantieri Marinette Marine (Lockheed Martin) launched the USS Cleveland (LCS-31). And in August 2024, Austal USA launched the final Littoral Combat Ship, the USS Pierre (LCS-38), the 19th multi-hull (trimaran) Independence class LCS and the 33rd LCS overall.

Finally, Updated MCM Sensors

In May 2023, the US Navy announced that the LCS Mine Countermeasures Mission Package (MCM MP) and Raytheon’s AN/AQS-20 Sonar Mine Detection Sets had finally achieved Initial Operational Capability (IOC). The MCM MP also completed missions with the Airborne Laser Mine Detection System (ALMDS) (AN/AES-1) in August 2022.

According to US Navy sources in 2026, the LCS MCM MP is a sophisticated suite of manned and unmanned systems designed to locate, identify, and neutralize sea mines at a safer distance from minefields than the older Avenger class MCMs with their AN/SQQ-32 sonar systems.

Untested LCSs with MCM Mission Package Replace  Avenger class Minesweepers in Gulf

Naval mine warfare in the Persian Gulf has long been a major tenet of Iran’s Islamic Revolutionary Guard Corps (IRGC) Navy military doctrine, according to a 2017 US Office of Naval Intelligence report. Iran reportedly began laying mines in the Strait of Hormuz in early March 2026, with the US Central Command announcing that it had initially struck 16 Iranian mine-layers from the air.

But the US Navy’s long-serving Avenger class Minesweepers USS Devastator, USS Dextrous, USS Gladiator, and USS Sentry — which were all stationed in Bahrain in the Persian Gulf — were retired in 2025 after each serving for over 30 years, leaving only four remaining minesweepers in the US Navy fleet.

In early 2026, the four remaining Avenger minesweepers were forward deployed to the US 7th Fleet at US Fleet Activities Sasebo, Japan.

Instead, in 2025 the untested Independence class (trimaran hull) Littoral Combat Ships (LCS) equipped with the Mine Countermeasures Mission Package (MCM MP) began arriving in the US Fifth Fleet to replace the decommissioned Avenger class minesweepers in Bahrain.

The USS Canberra was the first LCS with the MCM package to arrive in the Middle East in May 2025. The USS Santa Barbara and USS Tulsa LCSs with the MCM package were also stationed in the Fifth Fleet by September 2025, with a yet-to-be-named fourth LCS on its way, according to the US Navy.

Unlike the Avenger class minesweepers, which have a long battle-tested history, the LCS with the MCM package has never been deployed in combat.

The LCS with the MCM package theoretically has similar counter-mine capabilities to Avenger minesweepers, but with its aluminum hull, the LCS operates outside the mine threat zone and deploys off-board counter-mine devices, while the Avenger minesweepers can operate near or directly inside the mine-threat zone, with their non-magnetic signature and low acoustic footprint designed to avoid triggering sea mines. Both deploy a variety of resources to destroy and disable moored and bottom mines, including sonar, cable cutters, and mine detonating devices.

The LCS deploys unmanned vessels that carry the AN/AQS-20 towed mine-hunting sonar system, which uses sensors to pinpoint the location of bottom mines and moored mines.

There is also the unmanned influence sweep system, which provides common unmanned surface vehicles aboard the LCS with the ability to sweep or detonate mines through a magnetic sweep cable that emits a magnetic field or a towed acoustic device that emits sound. The unmanned vehicle moves along a predetermined route but sends camera footage and radar readings back to a remote operator who can steer the vehicle away from obstacles underwater.

The LCS ships do have a stronger weapons package compared to the Avenger minesweepers, but the LCS’s 57mm MK-110 gun system, SeaRAM self-defense system, and .50-caliber machine guns are still not very powerful in a contested area.

Teal Group Evaluation

All told, versions of the long-serving Raytheon AN AQS-20A/C & Northrop Grumman AN/AQS-24 MCM (Mine Countermeasures) systems will be worth $2.2 billion over the next ten years, with their primary future platform likely to be the looking-for-a-mission LCS, with as many as 24 MCM Mission Package (MP) systems to be procured – perhaps becoming the primary LCS sensor/mission.

And Teal Group’s new, speculative Future Naval MCM (Mine Countermeasures) Sensors forecast will see $1.9 billion in so-far uncontracted funding over the next decade, for various procurement programs and RDT&E.