Effects of compressibility at Mach numbers up to 0.8 on internal-flow characteristics of a cowling-spinner combination equipped with an eight-blade dual-rotation propeller

Report presenting an investigation studying the effects of compressibility on the internal-flow characteristics of an NACA 1-series cowling-spinner combination equipped with a dual-rotation propeller at Mach numbers up to 0.8. Two propellers were examined, one with a sealed propeller-spinner juncture and one with a raised-platform-airfoil shaped juncture. The propeller was not found to have appreciable compressibility effects on the impact pressures when operating at design cruise blade angle.