Bow thrusters usually have one or more tunnels built into the bow, below the waterline in order to improve manoeuvrability. Depending on the type of vessel, the range of application for bow thrusters extends from brief docking and casting-off in ports with a limited number of operating hours every year up to continuous operation under extreme load conditions in demanding offshore applications with dynamic positioning. Allow the ship to dock without the assistance of tugboats, saving the costs of such service.
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