Propulsion characteristics of multi-mode ships in aspect of ships dynamic positioning application

The dynamic positioning systems require multi-element ship propulsion application. The chosen solutions have decisive effect on propulsion system possibilities, in ship dynamic positioning accuracy also. The automation system has an essential influence on it, because it is an integral part with propulsion system mponsible for this process. The most often ship propulsion solution based on unconventional thrusters driven by electric motor s also. A few independent propulsion systems is essential but it complicates this system, it is limited the number (most often to 4, seldom more up to eight). There are no solutions with traditional rudder and steering gear. These functions take over azimuthing thrusters because they can generale directional thrust force. It must be settle the question of the number of thruster choose and the span angle of azimuthing (most often by thruster turning). In that case it gets the possibilities of ship positioning, they may display as propulsion system characteristics, giving a view on ąuality of positioning process. The last veriflcation is made in real sea conditions when it may test if chosen solution of ship propulsion system fulfils the requirements of positioning accuracy. It was presented the examples of multi-mode ship propulsions and parameters of theirs propulsion plants.