Arrangement and method for manoeuvring a floating vessel (1) that is towing a load (10), such as a trawl. The vessel has a block (4, 5) at the aft end, over which at least one tow line (6, 7) extends. The block (4, 5) is moveable transverse to the longitudinal axis of the vessel. The position of the moveable block (4, 5) defines a point of attack for a tension force from the tow line (6, 7). An autopilot (11) is coupled to an actuator (21) moving said block (4, 5) transverse of the longitudinal axis (24) of the vessel (1), in order to change the moment of force of the tension force (W) about a point on the longitudinal axis (24) of the vessel (1). The autopilot (11) is equipped with a calculation unit (12), which detects the tension force (W1, W2) of the at least one tow line (6, 7) and calculates the moment of force from the tension force (W) on the vessel (1). The autopilot is thus capable of using a change in said moment of force to manoeuvre the vessel (1).