MHC 51 Osprey
Coastal Mine Hunters

In the early 1980s, the US Navy began development of a new mine countermeasures (MCM) force, which included two new classes of ships and minesweeping helicopters. The vital importance of a state-of-the-art mine countermeasures force was strongly underscored in the Persian Gulf during the eight years of the Iran-Iraq war, and in Operations Desert Shield and Desert Storm in 1990 and 1991. The Osprey (MHC 51) class ships are mine hunter-killers capable of finding, classifying and destroying moored and bottom mines. MHC Class ships are the world's largest Glass Reinforced Plastic (GRP) ships and the first US Navy ships designed solely for minehunting.

The design is based on the Italian Navy Lerici Class. Voith-Schneider rotors replace the conventional propellers of the MCM and MSO classes. The MHC 51 has a 15-day endurance and depends on a support ship or shore based facilities for resupply. This mine hunter (coastal) is designed to operate from CONUS bases against enemy bottom and moored mines. The 12 Osprey ( MHC 51)-class mine hunters are smaller cousins of the Avenger-class and are used for harbor clearance, port breakout, and deep-water coastal mine countermeasures. The ship's hull is made of glass-reinforced plastic fiberglass.

The ship is designed to locate mines with sonar and neutralize them with a remotely controlled underwater vehicle. A precise navigation system is installed to integrate the minehunting sonar with the mine neutralization system. The ship is powered by two diesel engines driving two cycloidal propellers, a unique propulsion system that provides superior maneuvering and station keeping ability while the ship is operation in a minefield. The ship's mission is to clear harbor, coastal and ocean waters of acoustic, magnetic, pressure, and contact type mines, utilizing reconnaissance, classification, and neutralization tactics.

The MHC Class design integrates modern mine countermeasures technology into a uniquely designed platform with exceptionally low magnetic signatures to protect against detonations during minehunting operations. It is the first US Navy mine countermeasures ship to be constructed of Glass Reinforced Plastic (GRP). The plastic monohull design has no longitudinal or transverse hull framing -- the skin carries all the stresses. The vessel is flexible under shock, and machinery is supported by cradles from the main deck. Major equipment is mounted on cradles suspended from the overhead, decks, and bulkheads to provide for shock isolation and increased noise path. Additionally, nothing is hard mounted to the hull to provide for flexibility under shock. Even fuel and water tanks are suspended between bulkheads. Many major shipboard components are also constructed of special materials to reduce overall ship magnetic signature.

Osprey and Robin are the first two of the 12 coastal mine hunters slated to be decommissioned. These two Osprey-class coastal mine hunters were decommissioned 15 June 2006 in formal ceremonies at Naval Station Ingleside, Texas. USS Osprey (MHC 51), the lead ship in the Osprey-class, was decommissioned during a ceremony beginning at 10 a.m. USS Robin (MHC 54), was decommissioned during a ceremony beginning at 1:30 p.m. These ceremonies marked the end of the life of warships that served its country proudly. It also was the beginning of a new era of mine warfare. Osprey and her sisters' retirements were making the way for a new class of warship known as the littoral combat ship or LCS. LCS will continue where Osprey leaves off by carrying on and refining the Navy's critical mission of countering mine threats to the nation. Osprey and Robin completed decommissioning maintenance availabilities, then be towed to Beaumont, Texas.

Four MHCs were decommissioned in June 2006, with the entire class being decommissioned by the end of fiscal year 2008. Two Osprey-class coastal mine hunters were decommissioned 30 June 2006 in formal ceremonies at Naval Station Ingleside. USS Falcon (MHC 59) was decommissioned during a ceremony beginning at 10 a.m. and then at noon, USS Oriole (MHC 55) held her decommissioning ceremony. Falcon and Oriole were the second pair of the 12 coastal mine hunters that have been decommissioned.

Two Osprey-Class Coastal Mine Hunters, USS Heron (MHC 52) and USS Pelican (MHC 53), were decommissioned 16 March 2007, and transferred to the Hellenic Navy (HN) in the first official transfer of ships between nations at the South Texas base.