John W. McKee, Rodger L. Naeseth
An experimental study has been made of the drag of flat plates and cylinders in the slipstream of a hovering rotor. The slipstream was generated by a 6-foot-diameter two-blade rotor with constant-chord untwisted blades. The rotor, drive mechanism, and models were set up outdoors in an area surrounded by walls to minimize wind effects, the slipstream being directed upward to provide an unobstructed model test area and to simulate hovering away from the effect of the ground. Models as large as one with an area equal to 0.212 rotor disk area and a span equal to the rotor diameter were tested in a range of distances from the rotor of 0.10 to 1.33 rotor radii.
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