Naval aircraft are distinctively American types. Only one foreign seaplane was copied by the United States during the war, and when finally put into production it resembled the British prototype in externals only. While the Navy does a large part of its own designing and building through a corps of naval constructors, its theory of manufacture is to assemble parts procured from separate makers, and private design and construction are encouraged by contracting with builders. Available talent both in and out of the service and the facilities of parts makers, the new materials developed during the war and organized engineering which drove the entire process toward speedy results were appropriated by the Navy. The NC flying boat is typical of U. S. Navy practice. In the same way the dirigible C-5 is a purely American type.
The development of really large flying craft before 1917 was held back because no suitable engine had been designed. When the 350-hp. Rolls-Royce became available the four-engine Handley-Page plane was brought out in England, but no American engine was in sight until about August 1917, when preliminary work on the Liberty began to look promising. One of the weapons needed to keep down the submarine was the flying boat. By 1918 America had a large program for these and the Navy was at work on the larger types for quantity production in 1919. The author sketches rapidly but with some detail the development of every part of the NC-4. The special equipment used in the transatlantic flight is described. The paper is concluded with a description of the tests of the NC-3 at Rockaway. A number of curves are shown and a complete list of specification data is added.