What a smasher

One of the world’s most advanced ice-breaking vessels has made a spectacular entry to the water at a shipyard in Wisconsin.

The $90m (£48m) US Coast Guard cutter Mackinaw has been designed to force an open channel through the Great Lakes when the area’s ferocious winters render shipping lanes impassable to all other vessels.

The 73m Mackinaw can smash its way through 80cm of level ice at three knots, or broken ice piled up to 3m.

It is powered by three Caterpillar diesel engines and twin Azipod propulsion units, which its designers claim will give the vessel unrivalled manoeuvrability for a vessel of its type.

Built by shipbuilder Marinette Marine, the cutter is equipped with the latest communications, navigation and security technology, as well as a 20-tonne crane and an oil-spill recovery system, allowing it to deal with pollution hazards in the lakes.

The new Mackinaw and its 50-strong crew will operate from Cheboygan, Michigan.

After completing several months of tests it will eventually replace a veteran vessel of the same name, which has carried out ice-breaking duties in the Great Lakes since 1944.

Unlike its predecessor, which had little to do outside the ice-bound season, the technologically advanced new Mackinaw will be able to operate all year round as a general-purpose search-and-rescue and security vessel.