Voith Water Tractor
A tug driven by the Voith-Schneider propellers arranged in the forebody. Underneath the propellers there is a nozzle plate. Its nozzle effect increases the propeller thrust. It also protects the propellers against grounding and supports the vessel in the dock. There is an effective stabilizing fin located underneath the aft body. This provides adequate course stability and shifts the center of lateral resistance aft, thus increasing the lever arm between the propeller thrust and the pivot point.
One of the major fields of application for the VWT is in escorting large tankers with their hazardous loads safely through narrow, winding channels. Such water tractors are especially suitable for escorting supertankers at high transit speeds.