The Falcon had enough rudder control power to easily keep the yaw string straight. Go To Top Dynamics Investigation Classic aircraft, that is aircraft without feedback systems in the flight controls, have five dynamic stability modes. The short period is the most important pitch mode to the pilot because it is the mode that most impacts pitch maneuvering. Because of the long period, pilots can tolerate low phugoid damping. Lateral-directionally classic airplanes have Dutch roll, spiral, and roll modes.
Dutch roll is a coupling of roll and yaw oscillations that cause the nose to wander.
The frequency is high. Pilots like high damping. Spiral is the response to a bank angle disturbance. If positive, an airplane will roll back toward wings level. If the time for the bank angle to double is over about 12 seconds, pilots often do not notice an unstable spiral.