Aeronautics: New Engine, New Fuel

Nearly two years ago Pratt & Whitney motor experts flew for newsmen a plane equipped with what looked like an ordinary Wasp engine but which differed in an important respect: the engine had no carburetor, received fuel by direct injection into its cylinders. No more was heard of the experiment until last week when Pratt & Whitney announced that long-time tests had proved successful: a carburetorless Hornet engine of 525 h. p. had been installed in a Boeing mail plane for actual service. Advantages: direct fuel injection eliminates all carburetion troubles including the danger of ice formation in the carburetor during winter operation. Also, like the Diesel, it permits the use of cruder and less inflammable fuels. Successful tests were made with a “safety” gas recently developed by Standard Oil Co. of New Jersey. Producedby hydrogenation, this fuel will not ignite below 107° F. (“flash point”). The flash point of ordinary gasolines lies anywhere between 28° F. and 46° F.