© 2004 The Independent Fact Group


Naval Architect Anders Björkman's contribution regarding the IFG 2002.12.24 M/V Estonia analysis - damage on the forward bulkhead

By Anders Björkman

Damage on the forward bulkhead of MV Estonia

On Christmas Eve 02.12.24 the IFG posed the question how the upper part of starboard visor lug opening in the superstructure bulkhead plate of the Estonia could have been damaged - indented and buckled - as the visorlug itself is apparently seen still being fixed by the visor lock; the lug and a part of the visor support plate having been ripped off from the visor.

The IFG concludes that the damage must have been caused by the visor lug itself, when the visor was partly lose, permitting the visor and the lug to move towards the upper edge of the opening and denting and buckling the plate. This can evidently not take place, if the side lug was fixed from moving by the side lock locking pin in the closed position.

So how was the lug opening damage caused?

This writer has concluded that the visor did not cause the accident at all. The suggested scenario of the JAIC, that the visor got lose by wave forces and then, when it was free and fell off, ripped open the ramp so that water could enter the superstructure, is impossible. The simple reason is that a certain amount of water trapped in the superstructure would only have caused immediate capsize, when the Estonia would have turned upside down and floated with the bottom up on the undamaged hull. It never happened.

The writer therefore supposes that the Estonia suffered a massive hull leakage, e.g. a long fracture in the side shell plate structure below waterline, whereby a plate or welded connection split and allowed large amounts of water to enter one or more watertight hull compartments. The structural damage could, e.g. be inside the starboard stabilizer fin box, which was installed during 48 hours in January 1994. The fin was never tested as the electric and hydraulic installation was not completed at the yard. It seems that the first time the fin was actually used in severe weather was the night of the accident. It is possible that welded connection between fin box plate and side shell plate fractured - 5 meters long - and water entered at high rate.

Defective hull welding during repairs and modifications is a common cause of later structural collapse or damage in heavy weather. This writer believes that both the Erika and Prestige suffered from fractures starting in defective welding between new and old steel at repairs 12-18 months before respective tanker accidents and large oil spills.

The Estonia stabilizer fin box was installed eight months before the accident inside a watertight compartment on deck 0 and this compartment could only be reached via watertight doors, i.e. there was no access or sounding facility to this compartment from a deck above. Thus, when this compartment on deck 0 was filled with water due a hull leak, there was no way to know that the compartment was filled with water ... except by opening watertight doors in the forward (two doors) and aft bulkhead (one door) of the compartment. If one forward watertight door was open, a narrow corridor space would have been flooded and this space was similar to the stabilizer space, i.e. it could not be accessed from the deck above. If the forward watertight door in the "corridor" space was flooded, water would reach the sewage tank room on starboard side, which was equipped with an escape stairwell from deck 0 to deck 7. Thus if the forward and aft watertight doors of the dead "corridor" space were open, a leak at the stabilizer fin would flood three compartments, enough to cause loss of initial stability and a sudden list to starboard. Water could also spill up on deck 1 above through the stairwell in the sewage tank room and other openings (drains or down flooding hatches in deck 1).

It is not clear if the three compartments could have been pumped dry by the bilge system.

If the crew in the engine room aft of the stabilizer room tried to enter the stabilizer room by opening the watertight door (trying to stop the leakage), it would have resulted in immediate flooding of the engine room and subsequent sinking of the ship without capsize. The crew members would have been standing to their knees in water (and it is likely that they actually did that. Then they immediately evacuated the engine room).

It should be clear that the watertight doors in the stabilizer, "corridor" and sewage tank compartments on the Estonia were illegal. Access should have been only from the deck above and the doors should have been permanently welded tight.

Surviving crew members and stand-by crew members of the Estonia has informed that there were problems with the stabilizer installation, that there was water in the engine room and that the bilge pumps had been started prior to the sudden list, thus severe hull leakage and flooding of several watertight compartments causing the sinking is a reasonable hypothesis (which has not been investigated).

The visor fitted on the superstructure had therefore nothing to do with the accident. The German investigators suggest that the visor didn't fit and could not be locked properly and was secured by ropes to the superstructure. This writer has concluded that the Atlantic lock was probably damaged long before the final accident and not in use at all. The Atlantic locking bolt would therefore have been rusty and dirty. All documented damages of the Atlantic lock seems "old" caused by an impact from starboard to port, bending the Atlantic visor lug and tearing off the small lugs welded on the forepeak deck. No convincing evident has been presented by the JAIC to the effect that the Atlantic lock was undamaged and in use on the fatal voyage and damaged then by an external wave force. The Atlantic locking bolt was of course salvaged but thrown back into the sea before being photographed and properly examined.

However, the IFG asks how the upper part of the starboard side lug opening could have been damaged with the lug found connected to the locking bolt.

This writer is bold to suggest that the visor was still connected to the superstructure, when the Estonia sank, and was later simply blown off using explosives under water after the accident, so that the JAIC could blame the accident on the visor. The visor then, after being blown off, just dropped down to the sea floor below the wreck. Evidence of an explosion under water is, e.g. the 2 x 0.8 meters large hole with plate missing and sharp edges in the starboard superstructure front bulkhead adjacent to the visor lug openings, which was discovered and filmed and investigated by Gregg Bemis divers in August 2000. The IFG has not yet analysed and explained this big damage. There are of course other damages indicating one or several underwater explosions; deformed and fractured plates on the ramp (found by the IFG on various films).

If the side lock lugs were in the locked position, when the visor was blown off under water is not clear, as the Germans suggest that the visor and the lugs did not fit. One possibility is that only the port side lock was engaged at the fatal trip and was in fact ripped off the visor, when the Estonia sank, and therefore ended up as seen on the edited films, i.e. remained in the port recess located on the locking bolt.

However, the starboard locking lug was probably not engaged at the final trip. It could then have damaged the upper plate edge of the starboard recess as found and described by the IFG, either when the ship sank and when the port lug was ripped off or when the visor was blown off under water after the accident.

In either case the starboard visor lug was therefore still attached to the visor after the accident and this could evidently not be admitted by the JAIC. The JAIC must show that the visor was correctly locked before the accident. The obvious solution was then to simply rip off the starboard visor lug from the visor under water and reposition it in the recess on the wreck ... and then film it for the first time on 9 October 1994 suggesting that also the starboard visor lug was located on its locking bolt after the accident!

There was a lot of unreported underwater activity at the Estonia wreck early October 1994 and removing the visor from the wreck by explosives, removing the starboard visor lug from the visor and reposition it in the recess were probably some of these activities. To cover-up these activities the JAIC reported a false wreck position (2100 meters NE of the real position) and at the same time denied that the visor had been found (it was then still hanging on the wreck superstructure). The finding of the visor on 17 October "a mile West of the wreck" was another false announcement, as the visor was then in a position below the wreck. There is no evidence that the visor was found 1560 meters due West of the wreck. Filming of the visor prior to that date is mentioned in the SHK diary, even if no films can evidently can be found in the same archive.

Hopefully the above will contribute to solving the IFG riddle how the recess was damaged.


Anders Björkman Heiwa Co,
European Agency for Safety at Sea 03.12.25

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