Force tests have been made in the Langley 4- by 6-foot vertical tunnel to determine the aerodynamic characteristics of an NACA 0009 tapered semispan wing equipped with a plain and a balanced flap having three different included angles at the trailing edge.
A comparison was made between lift and hinge-moment parameter values as calculated by existing methods from two-dimensional data and the comparison showed that the differences between the measured values of the lift and hinge-moment parameters and the values calculated from two-dimensional data by lifting-surface theory were, in general, no greater than the differences between the measured values for wings of the same aspect ratio but with different chord distributions.
The effects of overhang, gap, and trailing-edge angle on the lift and hinge-moment parameters were similar to the effects previously found in tests of two-dimensional models. Interference between bevel and overhang was indicated by the fact that the incremental effects of the overhang on the hinge-moment parameters varied as the trailing-edge angle was increased.