Super-Motors

Detroit is a city of great manufacturing executives. None of them is greater than Alvan Macauley, President of the Packard Motor Car Co. A great, burly man with a firm yet benevolent face, a steady eye and a firm handshake, he combines perfect business efficiency with imagination and public spirit* At the present moment, the Packard Company may make tens of thousand of excellent automobiles per annum, but the production of a few super-motors for the Air Services pleases Mr. Macauley a great deal more.

The aero engine must meet much severer requirements than the automobile engine. It must work at a greater proportion of its full power most of the time, it must be more compact, more reliable, and above all it must be lighter.

A 1,000 horsepower locomotive may weigh 20 or 30 tons. A small Ford motor weighs over 200 pounds and develops only 25 horsepower or so. The Liberty motor weighs 873 pounds for its 400 horsepower, i. e. a little over two pounds per horsepower. The great object of the aero-engine design is to achieve the truly wonderful goal of one pound per horsepower. This is almost attained by the two new Packard motors, descriptions of which have just been made public by Mr. Macauley. The smaller of the two develops 500 horsepower at 2,000 revolutions per minute and weighs 700 pounds, or 1.4 pounds per horsepower. The larger develops 800 horsepower at the same speed and weighs only 1,072 pounds, or 1.34 pounds per horsepower. Both have stood up to the severest tests, in their normal position and inverted, on the testing block.

This is the result of two years' steady development work. While every new device is constantly being tried and suggested, progress in aero engines seems to consist in improvement of existing features, with gradual changes only. The strongest steel alloys are used throughout. Many parts are made totally of duralumin. The valve mechanism of the overhead type is driven by a cam system and placed in a housing of the lightest possible construction. The cylinders are of larger bore and shorter stroke than the old Liberty motors so that the height of the motor is diminished. The exhaust valves working in the terrific heat of the outgoing gases are cooled by a column of oil forced under pressure through the stems and heads of the valves with greater reliability of the valve system as the result. A specially designed magneto furnishes a double spark. The general appearance of the motor is not unlike a Packard twin-six automobile engine with two sets of six cylinders arranged in V form. It differs by its superiority.

The saving in weight of the motors themselves has a repercussion on the weight of the whole plane. In fact, the saving in motor weight is doubled, since less wing area is required and all dimensions of the plane go down correspondingly.

*Alvan Macauley, 53, began his career as a patent attorney, moved to the National Cash Register Co., then to the Burroughs Adding Machine Co. The latter organization was dilapidated; its product was imperfect, its personnel was inefficient. Mr. Macauley improved the machine, built a sales force to distribute it. In 1910, the Packard Motor Car Co., a small company making 2,000 cars a year, asked for his services. He turned it into the most enterprising motor car manufactory in the U. S. When the U.S. entered the World War, Mr. Macauley had just developed an airplane motor, called it the "Liberty-Packard," demonstrated to experts that it was the best airplane motor available. He was told that the U. S. would use his motor, promptly made 200 without a contract, deleted the name Packard, since he felt that to call it "Liberty" alone, "would insure cooeperation." He is custodian of an investment of $30,000,000, sponsor of 12,000 workmen.