Welcome to a chapter of the e-book Disaster Investigation.
2.19 No Water on the Car Deck caused the Accident
The inner bow ramp was allegedly found on the wreck superstructure partly open or, rather, almost closed.
After the Final report (5) was issued, it has been reported (33) that there were in fact great problems with the ramp prior the departure. The ramp was deformed - twisted - and could not be locked (which the Commission ignored to report - they concluded the contrary). The ramp was apparently leaking a little, but as it was located more than 2,5 meters above the waterline, water could only flow in, when the bow pitched into a wave every 6-7 seconds at the time prior to the accident. This water then flowed aft due to stern trim on the starboard side due to slight list and flowed out through the existing scuppers on the car deck. The water could be heard sloshing around by the passengers on deck 1 below. But it is assumed that less than 100 litres/min flowed in through this defect and that less than 3 000 litres of water ever sloshed around on the car deck due to the leaking ramp. This could never have sunk the 'Estonia'. But 3 000 litres of water makes a lot of noise, when it moves around.
The Commission had first announced in October 1994 that the ramp had only been part open throughout the whole accident. Assume then that the ramp was part open 60-70 cms at the top and 30-35 cms halfway up about 2,5 meters above the car deck. The area of the wedge shaped openings is about 0,82 m², where water flows in, when the car deck pitches 2,5 meters below a wave. We ignore the fact that the ramp was inside a 'tunnel', which blocked the openings. As stated the car deck is 2,5 meter over the waterline. Assume the pitch period was about 8 seconds and the relative motion about 4,5 meters. Then the two openings at the ramp sides were below water two seconds every eighth second - the remaining time the ramp was out of the water. Say that the inflow velocity was 3 meters/second. Then 4-5 m3 would have flowed in every eighth second, i.e. the inflow was 36-37 m3 per minute!
It would therefore have taken at least 15 minutes to fill the car deck with 600 tons, so that the ship would list 10-15 degrees! Such an event must have been detected by the crew! And the survivors reported a sudden, deep listing >30 degrees!
Then we have to assume that the ramp was suddenly pulled fully open - the Commission in December 1994 concluded just that and that it happened suddenly after 01.15 hrs, say 01.16 hrs as proposed in 1.17. But if the ramp was down and fully open, the open area in the fore of the superstructure, where water came in, was then about 15 m². With a speed of 7 m/s, and pitching as assumed above, 1 575 m3/minute would have flowed in! 2 000 m3 would have flowed in during 75 seconds.
Dr Huss states that it would have taken 28 minutes 1.9 but compare with Appendix 4 for more detailed calculations. With a fully open ramp in the fore of the superstructure the ship would have listed 34 degrees in 75 seconds, the windows would have broken in the deckhouse side and the ferry should have capsized like the 'Herald of Free Enterprise' in less than a minute after that. The 'Estonia' would have ended up floating upside down if 2000 tons of water had been loaded in the superstructure cardeck space.
But the 'Estonia' stopped listing and returned to equilibrium at 15 degrees list! After the initial loss of stability and equilibrium at 15 degrees list everything went very slowly. And the ship was rolling 15 degrees port and starboard around the equilibrium, so that 100's of passengers and many crew could escape during 5-10 minutes, when the roll was to port and the ship was almost upright. Then you would expect that all water on the cardeck simply flowed out again.
According the Commission only 1 000 tons of water suddenly entered the car deck at 01.15 hrs - the ship listed 15 degrees - and then the inflow stopped - the ramp closed itself or the ship stopped or turned.
The Commission states this, 1.9 and 1.17. But nowadays we know that the ramp was never fully open - it was not open at all! - and there was no water on the car deck that could have caused the accident 3.10. Only a little leak water was on the car deck at 01.00 hrs. And it could hardly have flowed down to deck 0 or deck 1 - and there, on deck 1, some passengers saw water on the deck! This water came from below! And it was in all probability caused by a collision and hull leakage.