Steer me sideways: icebreaker attacks pack ice side-on

A new breed of ice-breaking vessel that can clear wider swathes of ice will boost the development of global shipping lanes in the Arctic

THE clank of hammers, the grind of machinery and the crackle of welding torches echo in a seemingly endless shed at the Arctech Helsinki shipyard in Finland.

Since June, about 200 workers have been assembling the skeleton of the Baltika, the first of a new breed of ice-breaking ship designed to cut a wide path through Arctic ice with its asymmetric hull. On completion early next year, Baltika will enter service under the Russian flag, clearing the way for large ships bound for ports like St Petersburg in the Gulf of Finland.

Baltika will be in the vanguard of global shipping’s rush into the Arctic. Thinning ice is already luring vessels to the waters off Russia’s northern coast, which offer a shorter route from Europe to Asia than the typical passage through the Suez Canal. In 2012, 46 ships were granted passage by Russia’s Northern Sea Route Administration. This year, the number is already over 250.

For now, ice is the biggest hurdle to development of the route, and also hinders frigid ports in Finland and neighbouring Russia. Icebreakers can be hired as escorts, but they are typically only able to punch channels about 25 metres wide – too narrow for the larger classes of container ships. Doubling the escort widens the channel, but at greater cost.

At 76 metres long by 20 metres wide, the Baltika will use its unique asymmetric hull to cut swathes through the ice. Each of the three engine pods mounted around the hull can rotate to deliver thrust in any direction. These azimuth thrusters allow the vessel to swing round and attack the ice at an angle of up to 30 degrees (see diagram). Meanwhile, fuel and bilge water is pumped around inside the hull to shift the vessel’s centre of gravity for optimal ice-breaking. The idea is for the ship to be able to make headway in ice up to 60 centimetres thick, while carving a channel 50 metres wide – enough for large container ships to follow.

The asymmetric hull has a major drawback, though. Modelling shows that it will pitch and roll irregularly at sea, and pilots will have to learn how to sail the vessel to compensate. “There are lots of different operational modes for the ship, all of which had to be addressed when working out how to use the power from each of the three thrusters,” says Mika Willberg, project manager at Arctech. “But, finally, after having trained on a simulator, you end up being able to drive this vessel with a joystick system.”

The Baltika is expected to stay in the Gulf of Finland, but subsequent boats of its design could help open the Northern Sea Route to global shipping traffic. That includes oil and gas resources from the Arctic, which Russia is keen to develop.

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