Tuesday, February 18, 2020

If American shipbuilders were less experienced, they were also free of all those hindrances

From the excellent Perilous Fight by Stephen Budiansky, an account of the naval aspects of the War of 1812. Page 75.
If American shipbuilders were less experienced, they were also free of all those hindrances. And so the design that Humphreys drew up when the first frigates of the United States navy were to become a reality in 1794 was like none ever seen. With a nominal rating of forty-four guns, his frigate was not only longer but proportionately more slender than any other frigate of the day. The design also incorporated a number of striking structural innovations that liberated it from some of the constraints that had forced so many trade-offs on designers of warships in the past. A series of long, arcing diagonal braces, six on each side, three sweeping forward and three aft, hugged the inside frame of the hull and were tied to it every two feet with one-inch copper bolts. These “diagonal riders” were an entirely new idea, and they greatly improved the strength and stiffness of the entire structure while counteracting the tendency of the long ship to hog. The deck planking was pressed into service as a structural reinforcement too; four pairs of extra-thick planks ran fore to aft the length of the ship, each plank of the pair “joggled” into the other and to the beams below with interlocking cuts like a jigsaw puzzle. This also added to longitudinal stiffness. A series of mutually supporting stanchions and knees carried the weight from the top, spar deck to the gun and berth decks below, and finally onto the diagonal riders beneath, which made for a substantial boost in the gun-carrying capacity of the entire ship. The top deck of standard European frigates consisted of a quarterdeck aft and forecastle forward with only lightweight, narrow gangways running between them on each side and a large open hatch between them and the fore- and mainmasts. A total of about twenty carronades and chasers could be carried on the quarterdeck and forecastle of a typical British frigate. But Humphreys’s bracing system allowed for a nearly complete spar deck running flush fore to aft, broken only by the main hatch, with room and support for as many as twenty-six guns along its entire length.

No comments:

Post a Comment