During the Russian war of 1788 – 1790 , Sweden built three hemmemas of a new design . They were considerably larger , 44 @.@ 5 by 11 m ( 146 by 36 ft ) , and the number of oars were increased to 20 pairs . They also had some of the heaviest broadsides , even when compared with the much larger frigates of the high seas navy . The artillery officer Carl Fredrik Aschling had cooperated with Chapman to increase the main armament to twenty @-@ two 36 @-@ pounders and two 12 @-@ pounders , which increased the draft by about 30 cm ( 1 ft ) . The addition of diagonal bracers to reinforce the hull allowed the later hemmemas to carry guns more powerful even than those on the largest sailing frigates of the high seas navy . Due to their considerable firepower and relative size , naval historian Jan Glete has described the hemmemas as " super archipelago frigates " .