Investigation of the Influence of Fuselage and Tail Surfaces on Low-Speed Static Stability and Rolling Characteristics of a Swept-Wing Model

A wind-tunnel investigation was made in the Langley stability tunnel to determine the influence of the fuselage and tail surfaces on the static stability and rotary derivatives in roll of a transonic airplane configuration which had 45 deg sweptback wing and tail surfaces. The tests made in straight flow showed that the wing alone has marginal longitudinal stability characteristics near maximum lift. The variation of rolling-moment coefficient with angle of yaw of the complete model is almost the same as for the wing alone. The results of the tests made in simulated rolling flight indicate that for this model the effects of the fuselage and tail surfaces on the rate of change of the rolling-moment, yawing-moment, and lateral-force coefficients with wing-tip helix angle are small in comparison with the effect of the angle of attack on these rotary characteristics. The vertical tail produces larger increments of the rate of change of lateral-force and yawing-moment coefficients with wing-tip helix angle than the fuselage or horizontal tail.