NACA-TN-1377

Abstract

INTRODUCTION <br>An investigation has been made in the Langley 7- by 10-foot tunnel and in flight of the horizontal tail surface of a torpedo bomber. Preliminary flight tests of the airplane showed that a large undesirable change in trim force occurred when the flaps were extended and that the maneuvering forces were excessive. The wind-tunnel investigation was undertaken to determine the aerodynamic characteristics of the tail surface with various amounts of unshielded horn balance so that a satisfactory configuration could be determined. The variations consisted of removing part of the unshielded horn and adding it to the stabilizer. Flight tests of one arrangement were made to corroborate the wind-tunnel results. <br>The present paper gives only the details of the wind-tunnel investigation. The control characteristics obtained in flight are compared with those estimated from wind-tunnel data.