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sudden heeling took place, the list could not be compensated even partially with the heeling
tanks. The consequences are known.
The JAIC Final Report lists altogether 16 bow visor damages, which occurred during the
years 1973-1994 in the Baltic Sea on vessels built by various European shipyards. These
individual damages were in general not reported to authorities and collected and thus no
conclusions were drawn. Thus the MV Estonia case was not a separate failure, but a rather
culmination point for the safety problems in the Baltic ferry traffic. If this information would
have been collected and analyzed, preventive measures could have been taken before the
MV Estonia accident and not after it.
2.3 The Accident Scenario
The accident can be considered to have started already around 01:00 with the loss of the
bow visor. It is very likely that already before, the ramp was leaking, letting water onto the
vehicle deck, not least because the bow visor and ramp structures were slowly breaking. The
location of the visor, those of the debris from the vessel and that of the wreck on the seabed,
together with the survivors’ testimonies clearly show that the vessel made a turn to port. Most
likely already before the turn the vessel had heeled strongly to starboard as a consequence
of the massive inflow of water onto the vehicle deck. The heeling of the vessel was at least
partly related to the turning of the vessel. As a result of the reducing speed the centrifugal
acceleration reduced and the ship righted itself somewhat. The heeling during the turning
was so massive that the ventilation ducts ending at the ship side just below the Deck 4
submerged, and water could flow down into several compartments below the vehicle deck.
Simultaneously some water was flowing from the vehicle deck into the center casing and
further down into the passenger compartments below the vehicle deck. The draught of the
ship increased, which further increased the flow onto the vehicle deck through the opening at
the bow. At some point the strength of the windows at the ship side was exceeded and the
windows started to break causing the heeling further to increase. Little before starting finally
to sink the vessel probably had a list of about 125°-140° to starboard. The ventilation ducts
on the port side of the vessel, which submerge very late, allowed so much rest air from the
watertight spaces below the vehicle deck to escape that the vessel could sink. According to
the calculations of the HSVA-Consortium the vessel could sink with closed WT-doors under
the vehicle deck.
2.4 The Heeling and Sinking Process
� The accident can be considered to have started already around 01:00 with the loss of the
bow visor and not at 01:14 as stated by the JAIC.
� The bow visor detached from the MV Estonia as a result of structural failures in the deck
beams and locking systems of the visor.
� The structural failures were most likely caused by wave loads, which are normal
operational loads. The survivors’ testimonies and most other evidence support neither the
hypothesis of the visor loss being caused by an explosion, nor by a collision with a
submarine.
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