NACA-RM-L53E11

Abstract

INTRODUCTION <br>The present-day airplane with its high control forces has compelled the designer to resort to boosters to enable the pilot to control the airplane. The ability of these boosters and similarly the ability of missile control mechanisms to deflect control surfaces at rather high rates has raised the question of the effect of rate of control deflection on control characteristics. This effect could become especially important if the main lifting surface were at a relatively high angle of attack and the rate of deflection influenced the formation of separated or stalled air flow. It is conceivable for this condition that hinge moment could get Large enough to cause damage to the system before the mechanism had time to reverse and reduce the load. <br>There are considerable static control force and control effectiveness data available throughout the subsonic Mach number range; however, there is very little dynamic control force data available throughout this Mach number range. <br>It is the purpose of this paper to present the data obtained in an investigation of the effect of rate of flap deflection on flap binge moment and wing lift . The wing used had an aspect ratio of 4, a taper ratio of 0.6, NACA 634006 sectiom parallel to the plane of symmetry, and had zero sweep of the 75-percent-chord line. <br>The investigation covered a Mach number range from 0.32 to 0.98 for static condition of the flap and 0.32 to 0.87 for dynamic condition of the flap, with the Reynolds number varying from approximately 1.0 to 2.3 X l0⁶. The angle-of-attack range was from 0&#176; to 20&#176; and the flap angle varied from approximately 0&#176; to approximately 60&#176;. The rate of flap deflection varied from 0&#176; to 1.17&#176; per chord length of travel.