 The typical heavy frigate had a main armament of 18-pounder long guns, plus 32-pounder carronades mounted on its upper decks.The first 'super-heavy frigates', armed with 24-pounder long guns, were built by the naval architect F H Chapman for the Swedish navy in 1782.Because of a shortage of ships-of-the-line, the Swedes wanted these frigates, the "Bellona" class, to be able to stand in the battle line in an emergency.