 All of the wrought @-@ iron armor that was used in the Uragan @-@ class monitors was in 1 @-@ inch ( 25 mm ) plates , just as in the Passaic @-@ class ships . The side of the ship was entirely covered with three to five layers of armor plates , of which the three innermost plates extended 42 inches ( 1 @.@ 1 m ) below the waterline . This armor was backed by a wooden beam that had a maximum thickness of 36 inches ( 914 mm ) . The gun turret and the pilothouse above it was protected by eleven layers of armor . The conning tower armor was 11 inches ( 279 mm ) thick . Curved plates six layers thick protected the base of the funnel up to a height of 7 feet ( 2 @.@ 1 m ) above the deck . Unlike their predecessors , the Uragans were built without deck armor to save weight , but Koldun 's deck was reinforced by the addition of 0 @.@ 5 @-@ inch ( 12 @.@ 7 mm ) armor plates after completion . 
