NACA-TN-1049

Abstract

INTRODUCTION <br>In an effort to provide satisfactory methods for predicting control-surface characteristics, the NACA has undertaken a program of summarizing, analyzing, and correlating the results of various experimental investigations of airplane control surfaces. A collection of balanced-aileron test data is given in reference 1. Reference 2 presents a collection of data applicable to the design of tail surfaces. The results of analyses of data for control surfaces with internal balances, plain-overhang and Frise balances, beveled trailing edges, and unshielded horn balances have already been published in references 3 to 6. An analysis of the lift effectiveness of control surfaces is presented in reference 7. The present report gives the results of an analysis of the tab hinge-moment effectiveness based on the tab data of references 1 and 2 with additional data from references 8 to 2D. The terms flap and control surface are used synonymously in the present report. The data were obtained for the most part under conditions of low Reynolds number, high turbulence, and low Mach number. <br>No data are presented on the tab lift effectiveness, which determines the loss in control-surface lift effectiveness resulting from balancing-tab action, because this control-surface-lift effect can be evaluated as indicated by the analysis of reference 7.