Icebreaker
In May 2007, sea trials were completed for the nuclear-powered Russian icebreaker NS . The vessel was put into service by Murmansk Shipping Company, which manages all eight Russian state-owned nuclear icebreakers. The keel was originally laid in 1989 by Baltic Works of Leningrad, and the ship was launched in 1993 as NS "Ural". This icebreaker was intended to be the sixth and last of the "Arktika" class, and currently is the world's largest icebreaker.
Icebreaker
Today, most icebreakers are needed to keep trade routes open where there are either seasonal or permanent ice conditions. While the merchant vessels calling ports in these regions are strengthened for navigation in ice, they are usually not powerful enough to manage the ice by themselves. For this reason, in the Baltic Sea, the Great Lakes and the Saint Lawrence Seaway, and along the Northern Sea Route, the main function of icebreakers is to escort convoys of one or more ships safely through ice-filled waters. When a ship becomes immobilized by ice, the icebreaker has to free it by breaking the ice surrounding the ship and, if necessary, open a safe passage through the ice field. In difficult ice conditions, the icebreaker can also tow the weakest ships.