SCHRIFTENREIHE SCHIFFBAU Festschrift anlässlich des 100 ...

� After the mentioned 2-3 minutes the vessel must have turned away from the waves and
reduced speed. Otherwise it would most likely have capsized.
� The simulations show the high vulnerability of a vessel like MV Estonia to a serious
damage exposing the ship’s vehicle deck to open seas: The difference between a rapid
capsize and survival can be as low as about 30 seconds on the initial course and speed
with the ramp open.
� The sudden heel is probably also related to the start of the turn of the vessel initiated by
the officers on the bridge.
� The computed time-histories of the heeling angle shown in the figures show a high peak
just in the beginning, when the ship speed is high, the vessel starts to turn, and there is
already water on the vehicle deck. This high heeling angle is caused by at least three
factors: (1) the turning rate of the vessel; (2) the chosen random wave pattern realization;
(3) the amount of accumulated water on the vehicle deck.
� In the simulations the compartments below the vehicle deck can have a considerable
water ingress via the center casing relatively early during the course of the accident. The
Engine Room related spaces can be flooded at this phase only via the ventilation ducts
on ship sides. The inlets of these ducts are located just below Deck 4 and they submerge
below the sea surface only when the ship has a considerable heeling angle. The ingress
of water to the Engine Room related spaces is therefore likely to start later and is
somewhat slower than to the spaces flooded by water entering from the vehicle deck via
the center casing.
� The water flow down into the center casing from the vehicle deck and the flow through
the side ducts into the spaces below the vehicle deck significantly contributed to the loss
of the MV Estonia.
� The hydrostatic analysis of the TUHH showed that from that moment on, when the side
ventilation duct inlets were submerged, the vessel would irreversibly sink.
� In his testimony the passenger P76 describes how the window just outside the Karaoke
Bar on Deck 5 was partly submerged during the sudden initial heel. The simulations show
this, too. This implies that (1) The ventilation duct openings at the ship side just below the
Deck 4 had a hydrostatic pressure head of more than 3 m; (2) The large windows on
Deck 4 were loaded near to their estimated breaking load.
� The absolute breaking load of the windows could be estimated only crudely. Thus the
computed moment of time the windows break is not very accurate. As, however, the
larger windows are structurally much weaker than the smaller ones, it is very clear that
when the vessel heels to the side and the windows submerge, the larger windows break
first. As the larger windows are located in the stern and middle of the ship this fact
contributes to the vessel sinking stern first.
� The location of the visor, those of the various items dropped from the vessel and that of
the wreck on the sea bottom define the points, above which the vessel must have passed
54