Arktika-class icebreaker
The "Arktika" class is a Russian (former Soviet) class of nuclear-powered icebreakers. Formerly known as "Project 10520 nuclear-powered icebreaker", they were the largest and most powerful icebreakers until the 2016 launch of the ship named Arktika. Ships of the "Arktika" class are owned by the federal government, but were operated by the Murmansk Shipping Company (MSCO) until 2008, when they were transferred to the fully government-owned operator Atomflot. Of the ten civilian nuclear-powered vessels built by Russia (and the Soviet Union), six have been of this type. They are used for escorting merchant ships in the Arctic Ocean north of Siberia as well as for scientific and recreational expeditions to the Arctic.
Sampo (1898 icebreaker)
After the newest and most powerful state-owned icebreakers, "Voima" and "Jääkarhu", were handed over to Soviet Union as war reparations, Finland was left with four old steam-powered icebreakers and the small diesel-electric "Sisu", which had been rejected due to the extensive damage it had sustained in the war. The newest steam-powered icebreaker, "Tarmo", was almost 40 years old and along with the others long overdue for replacement — even the largest Finnish icebreakers were not wide and powerful enough to assist the biggest post-war cargo ships. There was also a severe shortage of coal and occasionally the Finnish icebreakers had to rely on firewood. The steam-powered icebreakers were completely overhauled for the last time in 1951–1952 when they finally received modern navigation equipment — even as late as 1952 some had neither gyrocompass, sonar nor radar — and their crew spaces were rebuilt to modern standards. There were talks about converting the furnaces of "Sampo" from coal to oil, but it was not deemed necessary as the old icebreaker was due to decommissioning in the near future.