"Wind-tunnel tests of several propeller, cuff, and spinner combinations were conducted in the 20 foot propeller-research tunnel. Three propellers, which ranged in diameter from 8.4 to 11.25 feet, were tested at the front end of a streamline body incorporating spinners of two diameters. The tests covered a blade angle range from 20 deg to 65 deg. The effect of spinner diameter and propeller cuffs on the characteristics of one propeller was determined" (p. 1).