Minehunter, Coastal (MHC)

Originally designed in Italy as the Gaeta Class for the Italian Navy, the RAN Huon Class has been modified to suit Australian conditions, including improved accommodation and mine hunting capabilities. The Huon Class featured a unique hull design, outstanding shock resistance and an inherently low magnetic signature, allowing the ships to operate in hostile mine environments. Each single skin monocoque hull was designed with no ribs, frames or stiffeners, avoiding local stress points that could separate under shock conditions. For their mine countermeasure operations the ships were fitted with a Variable Depth Sonar capable of detection ranges in excess of 1,000 metres ahead of the ship. When a mine was detected in a water column or on the seabed, the ship would 'hover' about 200 metres from the contact. A mine disposal vehicle or clearance divers would then be sent to investigate and neutralise the mine threat. Each ship was fitted with a pair of electrically powered Bofors Underwater Systems Double Eagle mine disposal vehicles equipped with a searchlight, closed-circuit low light television camera and an on-board close range identification sonar. Commands were relayed via a fibre optic link inside the vehicle's tether, which also relayed sensor images for display on the ship's multifunction console in the operations room. Each Double Eagle vehicle was fitted with either a disposal charge slung beneath or an explosive or mechanical cutter designed to sever the wire rope or chain holding moored mines.