Accidental damages of ships can occur in any number of ways being the two most concerning ones the collision with other ships and hard grounding on seabed. When a ship is damaged, the operators need to decide on immediate repair actions by evaluating the effects of the damage on the safety of the ship by considering simultaneously effects of the damage in the hull girder ultimate bending moment and in the applied loads. Recent disaster of the tanker „Prestige“ in 2002 close to the Spanish coast clearly showed that the ship in damaged condition can be broken and sink as the most unfavourable outcome of such accident with likely spillalge of a large amount of oil onboard.

The aim of the paper is to investigate if there is possibility of ultimate hull girder collapse of damaged oil tanker in the Adriatic Sea.  Location and extent of the damage due to grounding or collision are defined according to the ABS document „Guide for Assessing Hull-Girder Residual Strength for Tankers“.

Still water bending moments of damaged oil tanker are estimated using data from available references. Wave loads are calculated by seakeeping software applying 3D panel method. The most probable extreme values of the vertical wave bending moment during the towing period of damaged ship  is calculated using available wave statistics for the Adriatic Sea.

Ultimate vertical bending capacity of the intact and damaged ship are calculated by  MARS software and compared with other similar studies. Finally, safety factors against collapse of damaged ship are determined and corresponding conclusions are drawn.