ABSTRACT
This paper deals with a problem of propulsion system torsional vibrations of a catamaran vessel. Ship crew noticed significant vibration motions at some operating modes associated with changes in engine noise, temperature increase of flexible torsional coupling as well as with movement of angle bar for power change on the controller. Measurements and testing have been made to investigate and to eliminate the problem. The problem is described in details in the following chapter. A description of the problem is followed by a full detail measurement description. Further on, measurement and testing results are listed and commented. Finally, circumstances which lead to significant shaft line vibrations are detected.
