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The effect of blocking completely or partially one engine intake on the side force and yawing moment of the C-105 aircraft was investigated at supersonic speeds. A 1/80 scale model was tested in the 10 inch tunnel, the force and moment measurements being taken at a Mach number of 2.04. Schlieren photographs are presented for Mach numbers of 1.64 and 2.04. Over the whole range of yaw angles explored complete blockage of one intake resulted in a yawing moment (ΔCₙ =0.001) tending to put the blocked intake on the windward side of the fuselage.

Six-component supersonic wind tunnel tests were carried out on a 1/80 scale model of the C-105 aircraft at four Mach numbers. In all, 27 model configurations were investigated over a period of three months requiring a total of 1991 tunnel runs. This memorandum contains the results of these tests in the form of basic plots, cross plots and final aerodynamic derivatives. In order to expedite the publication of the data, the results are presented without detailed analysis.

Zero lift drag measurements of a 1/80 scale model of the C-105 aircraft were made in the 30-inch tunnel at subsonic and supersonic speeds. The Mach number range extended from 0.53 to 1.57 corresponding to a Reynolds number range of 1.2 to 1.7 x 10⁶ based on wing mean aerodynamic chord, see Fig. 1.

At supersonic speeds the values of C ₘₒ predicted and measured by the N.A.E. were found to disagree with the values measured by the N.A.C.A. In an attempt to discover a possible explanation for this discrepancy a detailed investigation was made in the area of interest and at a Mach number of 1.57. The effect of tunnel flow angularity was assessed by testing the model in both the inverted and upright positons while the effect of flow through the rather long and narrow intake ducts of the model was determined by testing the model with and without fairings over the intakes. In addition the effect of duct flow on the drag was determined at zero lift.