"The increase in world trade has largely contributed to the explosion in sea traffic. As a result, the market demand is leading to Ultra Large Container Ships (ULCS), which have a capacity up to 14,000 TEU with length up to 400 m, without changes of the operational requirements (speed around 27 knots). The particular structural design of the container ships, leads to open midship sections, resulting in increased sensitivity to torsional and horizontal bending loads which is much more complex to model. At the same time, due to their large dimensions, the ULCS become much “softer” and their structural natural frequencies become significantly lower so that the global hydroelastic structural responses (springing & whipping) can become a critical issue in the ship design and should be properly modelled by the simulation tools.On the other hand, it appears that the existing simulation tools do not provide the definite answer to all these design issues and there is a clear need for their improvement.The particular importance of whipping and the insufficient knowledge in its modelling is clearly reflected in the recent MAIB (Marine Accident Investigation Branch) report, following the loss of theMSC Napoli container ship:“It is likely that the hull of MSC Napoli was subjected to additional load due to whipping.”“… it is apparent that whipping effect is currently very difficult to reliably calculate or model.”“In view of the potential increase in wave loading due to whipping effect, further research is required to ensure that the effect is adequately accounted for in ship design and structural analyses, and that sufficient allowance is made for the effect when determining design margins.”The final goal of the project is to deliver clearly validated design tools and guidelines, capable of analysing all hydro-structure interaction problems relevant to ULCS."