Wright Whirlwind Engine in 1937




	The seven-cylinder Whirlwind model above had ratings of 235, 250, 285 and 320-350 horsepower.
	The single-row Whirlwind models of five, seven, and nine cylinders, which have been under development for over 16 years, were also refined during 1936. The ratings of the series were: five-cylinder 175 hp.; seven-cylinder 235 hp; 250 hp, 285 hp and 320-350 hp The nine-cylinder Whirlwinds of 330 hp, 365 hp, and 420-450 hp were characterized as "deluxe equipped" Whirlwinds due to their many standard and special features. These engines were provided with automatic valve gear lubrication, a new type of nose exhaust collector ring with built-in carburetor intake and air heater, dynamic damper counterweight, mechanism for the operation of the two-position hydro-control propeller, a three-way drive for the operation of a vacuum pump, a fuel pump, and a constant speed propeller governor, full pressure baffles provided with blast tubes for the cooling of the accessories and ventilation of the engine compartment and heating or cooling and ventilation of the cabin of the airplane; two mounting diameters provided by two sets of mounting lugs, the larger of which, corresponding with that of the Cyclone, provides greater accessibility in installations where the engine is mounted in rubber; complete radio shielding for ignition wiring, spark plugs, and magnetos, and the dynamic damper.
	Some of these features are also provided in the Whirlwinds of 250 hp, 285 hp, 330 hp and 365 hp. The following specifications are common to all Whirlwinds, parts of which are over 90 per cent interchangeable: bore, 5 inches; stroke, 5.5 inches and diameter, 45 inches. Weights, compression and blower ratios vary with individual models. The nine cylinder Wright Whirlwind J-5 was used in the Spirit of St. Louis. Development was continued in the higher horsepower categories with the double row Whirlwinds designed for military service. These engines now have ratings as high as 900 hp for take-off and 800 hp at 6,000 feet. The Curtiss Conqueror, a 12 cylinder V-type engine, used by the Army Air Corps for installation in high speed combat planes, was offered as a geared engine rated at 655 hp and 675 hp. The Conqueror is the only liquid-cooled engine built on a production basis in the United States. It may be operated with either water or Prestone as the coolant. The factory and foundry of the Wright Aeronautical Corporation at Paterson, N.J., comprises more than 650,000 square feet of floor space. During 1936 the Wright Company pioneered in the installation of Magnaflux testing equipment for the inspection of steel parts, nitriding equipment and furnaces to provide a super-hard bore in Cyclone cylinder barrels and machinery for the grinding of studs. All steel parts of Wright engines are subjected to the Magna flux test which shows up defects which might not be discernible under microscopes of 10 to 20 diameter enlargement strengths. The Wright installation of Magnaflux equipment, like its installation of nitriding equipment, were the first to be made in this country. During 1936 the Wright Aeronautical Corporation also, set up a modern experimental testing laboratory which is equipped to make endurance tests on engines of outputs up to 2,500 hp.