Koch (boat)

The Koch (Russian: коч; IPA: [ˈkotɕ]) was a special type of small one or two mast wooden sailing ships designed and used in Russia for transpolar voyages in ice conditions of the Arctic seas, popular among the Pomors.

Because of its additional skin-planking (called kotsa) and Arctic design of the body and the rudder, it could sail without being damaged in the waters full of ice blocks and ice floes. The koch was the unique ship of this class for several centuries.

The development of koch began in the 11th century, when Russians started settling of the White Sea shores. This type of ship was in wide use during the heyday of Russian polar navigation in the 15th and 16th centuries. There is documentary proof that in those days the private Russian civil fleet in the Arctic seas numbered up to 7,400 small ships in a single year. In the 17th century, kochs were widely used on Siberian rivers during the Russian exploration and conquest of Siberia and the Far East. In 1715, during the Great Northern War, the Russian Arctic shipbuilding and navigation were undermined by the ukase (decree) of Tsar Peter the Great. According to the ukase, only novomanerniye ("new-mannered") vessels could be built, that is the civil ships, which could also be used for military purposes. The koch with its special anti-icebound features did not suit this aim.

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