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In the years 2008/2009 the world economic crisis caused a reduction in the number of transported TEU, due to a significant decrease in transported goods. Consequently a great number of container vessels had been laid up or were forced to operate with a small amount of cargo on board. In this loading condition container vessels have a very high stability. In many cases their vertical center of gravity is even located below the lightship condition's coordinate. This is due to large amounts of ballast water in wing and double bottom tanks as well as no or only a small amount of cargo located at cargo hold bottom. The high amount of ballast water is needed to obtain an adequate hull and propeller immersion as well as a limitation of the longitudinal bending moments within the hull structure. In the typical loading conditions with higher amounts of cargo, less ballast water is needed ami the stability is lower. Under the described circumstances, several accidents have happened to container vessels during the last years. The accidents caused not only severe damages on ships but also heavily injured ami even killed crew members. They have been thrown through the bridge due to high transversal accelerations caused by heavy roll motions of the ship. This highlights, that modern container ship designs face some problems concerning insufficient seakeeping behavior. Since several accidents have happened to ships sailing under German flag, the BSU analyzed them by default. For three of the accidents, the seakeeping behavior has been examined in detail by order of the BSU at the Institute of Ship Design and Ship Safety at the Hamurg University of Technology (TUHH). This thesis shall examine the seakeeping behavior of several typical container vessels in equivalent environmental conditions.