sentences:  Two of Carleton's ships, "Inflexible" (18 12-pounders) and "Thunderer" (six 24-pound guns, six 12-pound guns, and two howitzers), by themselves outgunned the combined firepower of the American fleet.In addition to "Inflexible" and "Thunderer", the fleet included the schooners "Maria" (14 guns), "Carleton" (12 guns), and "Loyal Convert" (6 guns), and 20 single-masted gunboats each armed with two cannons.The American generals leading their shipbuilding effort encountered a variety of challenges.