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1.47 Various Points of View about the Speed of the 'Estonia' before the Accident. The Stern
The Final report (5) states that the speed of the 'Estonia' was 14.5-15.0 knots until one or two minutes after the listing had occurred; see figure 13.2 1.9. 3/E Treu has stated that the main engines were running normally and that no orders were given or carried out to reduce the speed, before or after the accident - the listing - occurred at 01.15 hrs.
On the other hand there are statements that the speed was reduced as early as one hour before the listing occurred 1.4 based on assumed observations of the lost Utö plot. The only evidence that the speed was unchanged seems to be the statement of Treu and we know today that Treu has lied 1.48. The Commission evidently had to suggest and maintain that the speed was unchanged in the severe weather and that the accident - the listing - came as a total surprise for the crew.
The Final report does not study what happens at the stern in heavy weather. The Commission has made model tests in June 1995 Appendix 2 to see what happened at the fore ship. Apparently very big wave impacts were recorded at the bow every minute, when the bow pitched into the waves. You would then expect that the propellers at the stern came out of the water and that the speed was automatically reduced.
The relative motion (movement up down relative the moving surface of the sea) seems to have been >five meters at the bow. By experience you know that the relative motion is about half at the stern, which means that the propellers should in fact have come out of the water in the model tests. However, the report of the model tests does not include any information what happened at the stern.
This writer believes that, before big impacts would occur at the bow (in any weather), the relative motion at the stern was so great that the propellers come above water and that the speed must have been automatically reduced, and that therefore big impacts at the bow could never have developed or occurred!