The Caldwell class was a class of six "flush deck" United States Navy destroyers built during World War I and shortly after. Four served as convoy escorts in the Atlantic; the other two were completed too late for wartime service. Two were scrapped during the 1930s, but four survived to serve throughout World War II, three of these in service with the Royal Navy under the Destroyers for Bases Agreement and the fourth as a high speed transport. Design and construction The six Caldwell-class torpedo boat destroyers were authorized by Congress under the Act of 3 March 1915, "to have a speed of not less than thirty knots per hour [sic] and to cost, exclusive of armor and armament, not to exceed $925,000.00 each ...Provided, that three of said torpedo-boats herein authorized shall be built on the Pacific Coast." Built from 1916 to 1918, the six ships of the Caldwell class were the first of 279 ordered (6 of which were cancelled) to a flush-decked design to remove the forecastle break weakness of the preceding and other "thousand tonners". They were effectively prototypes of the mass production and vessels which followed them, although somewhat slower ( vs. ) and differing in some details. The forward sheer of the Caldwell class was improved to keep "A" mount from being constantly washed out; however, this was unsuccessful. The Caldwells had a cutaway stern rather than the cruiser stern of the later ships, and thus had a tighter turning radius than their successors. The armament of the Sampsons was retained, but the broadside guns were relocated to "bandstands" aft of the bridge. There were differences in appearance; Caldwell, Craven and Manley were built with four "stacks" (funnels), while Gwin, Conner and Stockton had only three. The middle stack of the three-stack ships was wider due to combining two boiler uptakes. Once the mass-production destroyers made the design prevalent, the Caldwells and their successors became known as "flush-deck" or "four-stack" destroyers. was converted to a prototype high-speed destroyer transport (hull classification symbol APD) in 1939, with her forward stacks and boilers removed to give her the capacity to lift 200 Marines and four Higgins assault boats (LCP(L), LCP(R), or LCVP). She saw action at Guadalcanal, Kwajalein, Saipan, and the Philippines. Three entered Royal Navy service in 1940 under the Destroyers for Bases Agreement as part of the . , serving as HMS Leeds, provided