Navy's Planned Patrol Boat Fleet Will Distribute More Mine Clearance Capability

Navy Minesweeping Boats (MSBs) cleared mines
and fought their way through Vietnamese waters.

Sea mines are simple, affordable, and prolific, yet one of the most lethal weapons of naval warfare in the past 50 years.  Countering this threat remains a significant challenge for even the most advanced navies. The eleven remaining Avenger class Mine Counter Measures ships in the U.S. Navy's fleet are divided between two forward deployed home ports, Bahrain, and Sasebo, Japan.  These single purpose ships will be gradually phased out in favor of new unmanned, off-board mine clearance technology embarked on a variety of platforms, such as the Littoral Combat Ship.  

The Navy is also planning for smaller craft, such as the MK VI patrol boat to carry Unmanned Underwater Vehicles (UUVs) for mine clearance.  During the early days of Operation Iraqi Freedom, the Navy utilized small UUVs launched from the shore and inflatable zodiacs to find mines in Iraq's rivers. More recently, international navies have experimented with the concept of launching UUVs from rigid hull inflatable boats in Middle East waters during a series of mine warfare exercises. Additionally, a recent study by Lieutenant Andrew Thompson at the Naval Postgraduate school demonstrated that a variety of UUVs could prove successful in a large scale mine-clearance effort. Thompson's computer modeling concluded that factors such as UUV altitude, track spacing, number of passes, resupply, and search speed influenced the overall success and mission completion time of unmanned mine-hunting.

Though the use of unmanned vehicles aboard boats for mine clearance is a relatively new concept, fiberglass-hulled mine-sweeping boats (MSBs) served during the Vietnam War and even smaller wooden hulled boats, such as the 36' mine-sweeping launches (MSLs) served in World War II and Korea. Earlier mine-clearance boats focused on neutralizing mines in inshore waters with manual or acoustic sweeping gear.  New MCM boats with UUVs could conceivably conduct both shallow and deep-water mine-hunting.   

In support of this new distributed mine-clearance capability, the Naval Sea System Command (NAVSEA) Support Ships, Boats, and Craft Program Office (PMS 325) recently issued a request for information to industry to solicit assistance with requirements definition and procurement strategy in order to replace its large fleet of force protection boats currently serving with Naval Expeditionary Combat Command's Coastal Riverine Force.  Up to 100 of the 40 foot long boats, currently designated "PB-X," will be procured. 

ARABIAN GULF (May 2, 2015) Sailors assigned to Commander, Task Group 

(CTG) 56.1 unload a UUV from a rigid-hull inflatable boat during mine countermeasures training operations aboard the Afloat Forward Staging Base (Interim) USS Ponce (AFSB(I)-15). (U.S. Navy photo by Mass Communication

Specialist 1st Class Joshua Bryce Bruns/Released)

In addition to protecting harbors and inshore waters, the patrol boats will apparently serve in an a mine hunting capacity. According to the RFI, "the craft should be capable of launching, operating and recovering unmanned systems such as a MK18 Mine Countermeasures Underwater Vehicle System Mod MK 18 Mod 2." This UUV is based on the commercial Remus 600 UUV, commonly referred to as the Kingfish, and capable of operations at up to 600 meters in water depth.  

H/T Lee