Porter J. Perkins, Donald R. Mulholland
propeller for protection against icing : 50-percent partitioned blades The icing protection afforded an internal air-heated propeller blade by radial partitioning at 50-percent chord to confine the heated air to the forward half of the blade was determined in the NACA Cleveland icing research tunnel. A modified production-model hollow steel propeller was used for the investigation. Temperatures of the blade surfaces for several heating rates were measured under various tunnel icing conditions.
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