Curtiss Type OX-5 Eight Cylinder Aeroplane Motor
Hall-Scott Motors. These motors are made by one of the pioneer aeronautical motor builders, and have met with great favor. They are of the vertical water-cooled type, and with the exception of minor details and weight are very similar in external appearance to the automobile motor. Four and 6-cylinder types are built.
Sturtevant Motors. These are of the "V" water-cooled type, and are provided with or without a reducing gear. At least one model is provided with lined aluminum cylinders.
Dusenberg Motor. This is a four-cylinder, water-cooled, vertical motor with a very peculiar valve motion. The valves are operated by long levers extending from the camshaft. Two inlet, and two exhaust valves, are used per cylinder. The motor is generally furnished with a reducing gear.
Roberts Motor. This is a solitary example of the two-stroke cycle type, and has been used for many years. It is simple and compact, and is noteworthy for the simplicity of its oiling system. The oil is mixed with the gasoline, and is fed through the carbureter. This is one of the many advantages of a two-stroke cycle motor.
Table of Aeronautical Motors. The following table will give an idea as to the general dimensions of American aeronautical motors:
The Liberty Motor. The necessity of speed and quantity in the production of aeronautical motors after the declaration of war caused the Government to seriously consider the design of a highly standardized motor. This idea was further developed in a conference with representatives of the French and British missions on May 28, 1917, and was then submitted in the form of sketches at a joint meeting of our allies, the Aircraft Production Board, and the Joint Army and Navy Technical Board. The speed with which the work was pushed is remarkable, for on July 3rd, the first model of the eight cylinder type was delivered to the Bureau of Standards. Work was then concentrated on the 12 cylinder model, and one of the experimental engines passed the 50 hour test August 25, 1917.
It is of the "V" type with the cylinder blocks at an angle of 45 degrees instead of 60 degrees as in the majority of 12 cylinder "V" motors. This makes the motor much narrower and more suitable for installation in the fuselage, and in this respect is similar to the arrangement of the old Packard aviation motor. It has the additional advantages of strengthening the crank case. The bore and stroke is 5" x 7" as in the Hall-Scott models A-5 and A-7. The cylinders combine the leading features of the German Mercedes, the English Rolls-Royce, Lorraine-Dietrich, and Isotta-Fraschini. Steel cylinder walls are used with pressed steel water jackets, the latter being applied by means of a method developed by the Packard Company. The valve cages are drop forgings, welded to the cylinder heads.