This project is finished.
After the founderings of the RoRo ferries MV Herald of Free Enterprise in 1987 and MV Jan Heweliusz in 1993, MV Estonia was the third total loss of a ferry in the waters of northern Europe within a few years. All these three ferries had one thing in common: an end-to-end RoRo deck. Soon after the MV Estonia disaster several north European countries committed the so called "Stockholm Agreement" in 1995, which deals with a specified amount of water on the Main Car Deck additionally to the existing rules. Numerous rumours concerning the sinking of MV Estonia and a major change in damage stability regulations in 2009 putting the "Stockholm Agreement" into question - were the reasons for the governmental agency VINNOVA to investigate the foundering of MV Estonia again. Two independent research consortia carried out this research project, one under the leadership of the Swedish ship model basin SSPA and the other one under the leadership of the German ship model basin HSVA. The Institute of Ship Design and Ship Safety (M-06) of Hamburg University was a member in the HSVA-Consortium, opening the opportunity to have insight in documents of non public access.
This research project reconstructs the sinking sequence of MV Estonia in the Baltic Sea due to the sequence of time and to chain of causation aiming for an improvement of the ship safety in general but especially of RoRo type of vessel. The starting point of this project was the investigation and evaluation of the testimonies of the survivors via a synopsis, firstly used in this context. The testimonies and numerical calculations reconstruct the following sinking sequence: Sea loads on the bow visor lead to a failure of its locking devices. Through out an upper extension of the bow ramp in a box like housing, the drop off the visor ripped the bow ramp open and a large amount of water flushed on the Main Car Deck of the RoPax ferry. Due to the quick water ingress the vessel was destabilised and capsized to a quasi equilibrium floating condition at about 30° of list to the starboard side. At this heeling angle the vessel remained for a few minutes till the first ventilation duct was immersed. The mainly symmetric arranged ventilation system played a decisive role within the sinking sequence. From the immersing of the ventilation opening, a progressive flooding started. At a list of about 130° the stern of the ferry hit the sea floor and after this the bow section sunk.
The result of this research project is a reconstruction of the foundering via sensitive modelling and simulation was evaluation by survivors to be realistic. Further results are the arrangement of ventilation openings must not immerse at large heeling angles and a very instrument of ship safety is a sufficient free board to the Main Car Deck of RoRo and RoPax vessels. Finally, the SOLAS regulations have to be fulfilled.