Classification
There are two main classifications of koch subtypes. The first, a mixed classification, distinguishes between three subtypes of kochs depending on both their place of origin (Siberian and Mangazeyan) and their sea-worthiness (morskiye, that is "seafaring"). The second classification does not pay any attention to minor shipbuilding differences and divides all kochs into two categories according to the main spheres of their maritime operations: river/sea, and morskiye (seafaring) for long-range sea voyages.
The following is added from Fisher. He claims that the koch had a square sail and only one mast. The largest koches were 60 feet long and 20 feet wide(sic), with a draft of 5 or 6 feet and a crew of 6 to 12. They could hold up to 40 people or 45 tonnes of cargo. They were oval when viewed from the top or side. The flat or rounded bottom made them maneuverable when dodging ice floes, but probably unstable in a severe storm. The square sail and flat bottom meant that they would not sail well without a following wind.
Other boat types used in Siberia: Shitik, Baidarka.
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