An investigation was made in the Ames Aeronautical Laboratory 7- by 10-foot wind tunnel of the effects of various modifications to the profile of a 0.20-chord plain sealed aileron and a 0.15-chord plain sealed aileron on an NACA 66,2-216 (a = 0.6) airfoil. Aileron profiles tested consisted of one profile conforming to the normal NACA 66,2-216 (a = 0.6) ordinates; a profile consisting of straight-line surfaces from the trailing edge to the hinge-line ordinates; an intermediate thickened profile; and a profile thinned below the normal airfoil ordinates. Thickening of the aileron profile was found to reduce the aileron effectiveness, reduce the slope of the wing section lift curve, and reduce the hinge-moment coefficients. Thinning the profile had the opposite effect. The effects of profile on the aileron characteristics decreased with increasing angle of attack, there being practically no effect at an angle of attack of 12 deg. Thickening the profile caused a slight increase in minimum profile-drag coefficient, but thinning the profile had no effect. It is demonstrate that deviations of the order of + or - 0.005c sub a from the specified profile on the ailerons of a typical pursuit airplane can cause stick-force variations of + or - 20 pounds for a large rate of roll at an indicated airspeed of 300 miles per hour. It is also shown that the danger of overbalance at small deflections of closely balanced ailerons can be diminished by thickening of the aileron profile if the internal-balance chord is simultaneously reduced to maintain the same stick force for a large rate of roll.
Wind-Tunnel Investigation of Ailerons on a Low-Drag Airfoil. 1 - The Effect of Aileron Profile
1944
65 pages
Report
No indication
English
Aeronautics & Aerodynamics , Ailerons , Aircraft , Airfoils , Airspeed , Angles , Deflection , Low drag , Profiles , Surfaces , Thickness , Trailing edges , Wind tunnel tests , Ati-13964 , Ati collection
Wind tunnel investigation of ailerons on low drag airfoil
Engineering Index Backfile | 1944
|Wind-tunnel investigation of ailerons on low-drag airfoil. III -- Effect of tabs
Engineering Index Backfile | 1944
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