Analysis on Motion Stability of High Speed Underwater Vehicle in Longitudinal Plane

In order to study cavitation drag reduction of a high speed underwater vehicle, we establish a longitudinal motion model of the vehicle in supercavitation condition, analyze the step responses of attack angle and pitch angular velocity of the vehicle under turbulence in the balance state of cruise phase, and also analyze the motion stability through the root locus method. The results show that the vehicle can exhibit static stabilization under given balanceable attack angle and rudder angle, which is beneficial to keeping stability of a high speed underwater vehicle with straight running trajectory.