Porte then designed a similar hull for the larger Curtiss H-12 flying boat which, while larger and more capable than the H-4s, shared failings of a weak hull and poor water handling. The combination of the new Porte-designed hull, this time fitted with two steps, with the wings of the H-12 and a new tail, and powered by two Rolls-Royce Eagle engines, was named the Felixstowe F.2 and first flew in July 1916, proving greatly superior to the Curtiss on which it was based. It was used as the basis for all future designs. It entered production as the Felixstowe F.2A, being used as a patrol aircraft, with about 100 being completed by the end of World War I. Another seventy were built, and these were followed by two F.2c, which were built at Felixstowe.