Tests of the unique advanced submarine "Saint Petersburg" soon start in the Baltic sea. The ultramodern diesel submarine was designed for Russian Navy and doesn't have any analogues. The submarine is notable for its high combat capacities, fair speed and cruising range. "Saint Petersburg" is able to stay underwater without refueling for 45 days.
Moreover, the submarine has low noise level and is equipped with unique systems of environmental security. All mentioned systems would be tested in a naval cruise.