 The timing of the redesign proved to be <unk> as the Great <unk> was spreading through the ranks of the military and related industries . The original deadline for completion of design work by 15 October was missed , and an incomplete version was presented to the navy 's Shipbuilding Administration the next month . A number of details remained to be worked out , including the final design of the machinery plant , the 152 mm guns and the 100 mm gun mounts . In the meantime , extensive and expensive testing was conducted on the ship 's hull form , deck armor and torpedo protection ; 27 million <unk> were spent on experimental work in 1938 alone . Over 100 models of the hull were tested in a ship model basin to find the best hull form and two one @-@ tenth @-@ scale launches were built at Sevastopol to test the hull 's maneuverability . An old steamship was fitted with a replica of the design 's armor decks and tested against 500 @-@ kilogram ( 1 @,@ 100 lb ) bombs , proving that such ordnance would generally penetrate both the 40 @-@ millimeter ( 1 @.@ 6 in ) upper and 50 @-@ millimeter ( 2 @.@ 0 in ) middle decks before exploding on the armored deck . The main armor deck was raised one deck in consequence and a splinter deck added underneath it to stop any bomb or shell fragments that might penetrate the armor deck . The underwater protection system was tested on fifteen one @-@ fifth scale models and two full @-@ sized experimental barges . These tests proved that the torpedo belt system of multiple bulkheads was superior to the Pugliese system of a large tube filled with smaller sealed tubes , but it was too late to incorporate these test results into the design as construction was well underway by the time they were completed in late 1939 . 
