Theoretical load distributions on fin-body-tailplane arrangements in a side-wind

Abstract

A theory has been developed for calculating the distributions of sideforce and lift on fin-fuselage-tailplane arrangements in a side-wind but with the tailplane set at zero incidence. The analysis is limited to incompressible flow and has been further simplified by assuming that the geometrical arrangement is in each case such as to give constant induced sidewash. The results, which can be extended to other arrangements and to compressible sub-critical flow, are required for stability and stressing analyses. This paper is a continuation of an earlier note by the first author (Ref. 1), where the interference between fin and fuselage was considered. The addition of the tailplane introduced into the present report brings considerable changes in the load distribution as well as in the overall forces. The actual calculation procedure is very simple and quick since the main functions needed are presented in tables and charts for representative cases. The results for other geometrical arrangements can be obtained by interpolation.