This thesis reports on the construction of a 1/12th scale model of the award winning Arapaho attack helicopter design and wind tunnel test to determine both the model and full scale equivalent flat plate area. Tests were conducted for lg level flight and included yawed flight conditions up to 10 degrees. The significance of equivalent flat plate area for helicopters is that it is the principal parameter that establishes rotor propulsive force requirements. The Model was constructed from the original design submitted by the 1993 NPS Helicopter Design Team and is 47.5 inches long with a 48-inch main rotor diameter. The model was tested in the NPS Low Speed Wind Tunnel to measure the drag force on the main body of the model at wind tunnel velocities up to 72 knots. Drag force on the model was also measured with the rotor head and longbow radome installed, and at various yaw angles up to 10 degrees. The equivalent flat plate area was then calculated from these measurements and compared to other helicopters. Recommendations for further wind tunnel testing were made.
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