HMAS Yarra (IV)

Commissioned on 1 March 2003, HMAS Yarra (IV) is the sixth of six Huon Class Minehunters Coastal (MHC) vessels. The Huon Class MHC was designed in Italy as the Gaeta Class for the Italian Navy. The RAN Huon Class includes modifications to suit Australian conditions such as improved accommodation and mine hunting capabilities.

The Huon Class Minehunters are named after Australian rivers. Yarra is the fourth RAN ship to carry the name. HMAS Yarra (I) was a River Class Destroyer that served during World War I.

The Huon Class features a unique hull design, shock resistance and an inherently low magnetic signature, allowing the ships to operate in hostile mine environments. Each hull was designed with no ribs, frames or stiffeners to avoid local stress points that could separate under shock conditions.

For mine countermeasure operations, the ships are fitted with a Variable Depth Sonar capable of detection ranges in excess of 1,000 metres ahead of the ship. When a mine is detected in a water column or on the seabed, the ship will 'hover' about 200 metres from the contact. Mine disposal vehicles or clearance divers are deployed to investigate and neutralise the mine threat.

Each ship is 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 are relayed via a fibre optic link inside the vehicle's tether, which also relays sensor images for display on the ship's multifunction console in the operations room.

Each Double Eagle vehicle is 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.