Measurement of the dynamic lateral stability of the Douglas D-558-1 airplane (BuAero No. 37971) in rudder kicks at a Mach number of 0.72

In the course of a stability and control investigation of the D-558--1 airplane, rudder kicks were made at a Mach number of 0.72 at a pressure altitude of 8500 feet. The lateral oscillations resulting from the rudder kicks required 1 1/2 seconds to damp to half amplitude and had a period of 1.1 seconds. The Navy requirement which specifies the damping of lateral oscillations was satisfied by a small margin. The oscillation damps completely leaving no residual constant amplitude oscillation. The yawing oscillation produces an oscillation in pitch which apparently is caused by the gyroscopic moment of the engine.