the ukrainian fleet was largely surrounded by the russian fleet and thus inoperable by the ukrainian command. on the donuzlav lake since the night between 5 and 6 march, seven ukrainian vessels were blocked by sunken russian vessels. lutsk (u205), vinnytsia (u206), chernihiv (u310), cherkasy (u311), henichesk (u360), kirovohrad (u401) and konstyantin olschansky (u402)