SCHRIFTENREIHE SCHIFFBAU Festschrift anlässlich des 100 ...

this system could be switched off, whereas it is not known, whether this system was in
operation in the night of the accident. Therefore it was not taken into account in the HSVA-
Consortium analysis.
If the system was in operation, it may have contributed to the MV Estonia disaster as follows:
The ship was incorrectly loaded, the port side heeling tank was full, the starboard one empty.
When the ship got a heavy list to starboard, it can be expected that somebody on the bridge
tried to close all WT-doors, with the consequence that the valve in the cross-flooding duct
opened. Thus water from the higher port side heeling tank would flow down to the lower
starboard side heeling tank and increase the heeling angle of about 8°. This would have had
two adverse effects: It would lead to increased difficulties in abandoning the ship and also to
earlier tripping of the auxiliary engines generating power. The automatic connection of the
opening of the valve in the cross-flooding duct to the closing of the WT-doors is here
regarded as a potentially dangerous system.
The purpose of this investigation has been to throw light on the MV Estonia accident in
September 1994. Some information provided by this investigation is new, but certainly not all,
as we have come to similar conclusions than previous researchers. Some recommendations
on ship safety were made in this study.
In general some findings of the past MV Estonia investigations have already been included in
the actual international regulations related to ship safety. According to Luhmann, Meyer
Shipyard, (2008) such are, e.g. the “water on deck” requirement of the Stockholm
Agreement, the handling of cross-flooding valves, the availability of LSA in severe conditions
of list and trim, the location of the collision bulkhead and the height of downflooding points
from the vehicle deck.
The regulations have also otherwise been updated since the delivery of the vessel in 1980.
In the framework of this study it has not been possible to check, whether similar changes as
discussed here have after the accident been included in the actual rules related to ship
safety or are under the discussion at IMO level. If so, some of the recommendations or
suggestions given may be obsolete from the point of view of updating rules. Their technical
validity remains.
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