AIR FORCES on Radial Air-Cooled Engine Cowling - (as Determined from Pressure Distribution Tests)

THE purpose of this paper is to discuss some of the factors influencing engine cowl surface pressures; to present and analyze the results of pressure tests on one cowl model in the wind tunnel and on three representative cowl designs in flight; and to suggest methods of applying pressure-distribution data to the stress analysis of other cowls. The flight-test data presented are taken from test reports of the United Aircraft Corp.

The structural design of an engine cowl is a matter of considerable importance. Because continued improvement in airplane speeds and the increased severity of tactical maneuvers have increased greatly the aerodynamic forces on the cowling, the need for data from which to calculate these air loads has become increasingly imperative, especially for certain military types which are required to execute terminal velocity dives.