while curtiss's v-x-x engine proved to be inadequate, as it did in its larger model h cousins, the liberty proved more suitable, and large orders were placed by the us navy for the hs-1l. the hs-1 was armed with two 180 lb (80 kg) depth bombs, but it was found that these bombs were too small. in order to carry more powerful 230 lb (100 kg) bombs, curtiss produced an increased-span version, the hs-2 with span increased by 12 ft (3.66 m) and an additional set of interplane struts, giving four-bay wings rather than the three-bay wings of the hs-1l. again, curtiss specified one of their own engines, and again, the navy substituted this with the liberty engine in the definitive hs-2l.