Today all shipping industry working in very tense market. Time and fuel saving play more and more important role. To respect this lot of ships implement Condition Based Maintenance (CBM) what include Non Destructive Test (NDT) and monitoring systems. It is known that most expensive vessel’s parts are hull and engine crankshaft. Cracks in ship`s hull and large size engine parts, such as a crankshaft, are quite a common occurrence. The sources of these cracks are the different loads influencing the vessel, non- compliance with manufacturing technology, material fatique, etc. In order to prevent drastic consequences, detection of these cracks in the very early formation stage is extremely important. Today many companies and major Classification societies are involved in projects for monitoring systems implementation. The goal is to improve vessel’s safety and extend dry-docking and repair intervals using these systems as part of CBM. Riga Technical University started research works in that field in autumn 2012.