Max C. Kurbjun
naca-tn-4068
Aug 1957
In order to obtain information on the effects of blade plan form on the near-field noise of propellers, a series of measurements have been made of the oscillating pressures near a tapered-blade-plan-form propeller at flight Mach numbers up to 0.72. Flight Mach number, power, and engine speed were controlled in an attempt to duplicate the conditions of the flight investigation reported in NACA Technical Note 3417, where oscillating pressures were measured near a rectangular-blade-plan-form propeller.
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