The Cooling of Radial Engines

THE remarkable strides made by designers of commercial and military aircraft during recent years have been most strikingly evidenced by the ever-increasing performance of their products. This progress has been gained, to a great extent, in two ways: by improving the aerodynamic cleanness of the aeroplane and by increasing the specific power output of the engine. However, the successful utilisation of both methods has been complicated by the difficulty of providing the higher-powered engines with proper cooling and accessibility while retaining the cleanness of the aeroplane. Each addition to the power-plant output has not only further complicated that unit and made necessary more controls and accessories, but has also made the engine harder to cool. Designing the cowl to favour the cleanness of the aeroplane has often proved to be detrimental to both proper cooling and accessibility.