Pure Yaw Experiments on a Series of Hull Forms for an Underwater Vehicle: Hydrodynamic Observations and Analysis

Results from towing tank experiments for pure yaw or zigzag manoeuvres on a series of five axi-symmetric hull forms for an underwater vehicle are reported. The length-to-diameter ratio of the bare-hull version of the underwater vehicle models was in a range of 8.5 to 12.5. The coupled sway-yaw motion for pure yaw manoeuvres resulted in sway amplitudes of up to about six diameters, maximum yaw angles of about 15 degrees, and, a maximum turning rate of 17 deg/s. These manoeuvres resulted in new observations concerning the hydrodynamics of underwater vehicles which are presented in the paper.