The Browns Bay Shipwreck: Its Design and Construction, Parks Canada Research Bulletin

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At the beginning of the Seven Years' War, the British Navy developed a boat type especially designed to be used in amphibious operations to load and unload troops and equipment. […] However, the first record of the building and use of these boats occurs during the Seven Years' War, when the British sent an expeditionary force against France in 1758, and invaded Havana in 1762.

The flat-bottomed boats used in the Havana invasion were described as "clinker-built, of shallow draught, thirty-eight feet long, and eleven feet wide" […]

[…]The Americans, too, had developed shallow draft gunboats for use in lakes and rivers and for harbour defence. […] Therefore, a small fleet of these vessels was maintained to provide defence of the colonies along the waterways. The boats, under the control of the military, were described as: [...] some forty-five feet long, ten foot beam and were about five feet deep amidships [...] floated on a loaded draft of about two feet, exclusive of keel. The bows and sterns were decked for a few feet, but the central part of the hulls were open[…]

The Browns Bay Vessel had sunk 300 feet (90 metres) from shore in approximately six feet (2 metres) of water. […]

The Browns Bay Vessel is a wooden-hulled boat possessing an overall length of 54 feet, 2 inches, a maximum beam of 16 feet, 2-1/2 inches and a depth of hold of 3 feet, 6 inches. […]

The keel of the Browns Bay Vessel is of white oak (Quercus spp.). It measures 49 feet, 3-1/2 inches long and averages 8-3/4 inches moulded (height) and 6 inches sided (width) […]

The hull shape of the Browns Bay Vessel (Fig. 10) can be favourably compared to that of a launch ca. 1800. […]

[…]The features inherent in the clench-built hull — great longitudinal strength, thin planking, and light framing — were retained and enhanced. […]

The tonnage (tons burthen) of the Browns Bay Vessel is calculated as 20.8 long tons (21.1 metric tons) […]

[…] it is unlikely that a vessel with such a long, shallow hold was completely decked[…]