Surveying of ferry Estonia wreck has brought no surprises yet

  • 2021-07-14
  • BNS/TBT Staff

TALLNN - Summing up the surveying of the ferry Estonia wreck on the first days of this week, Rene Arikas, head of the Estonian Safety Investigation Bureau, said that although the amount of data collected already exceeds that of previous surveys, no immediate surprises have yet been identified, Postimees reported. 

According to Arikas, the surveys conducted on June 12 and 13 were successful: the equipment  did not fail, and the weather was very good. The survey group carried out studies with a side scan sonar and a multibeam sonar on the vessel Electra belonging to Stockholm University, which give an excellent overview of the wreck of the Estonia and the seabed surrounding the wreck.

"We are getting a three-dimensional image," Arikas said, adding that all this is needed to understand where to start the main survey and to get a detailed picture of the whole area.

According to Arikas, the seabed was also explored with a profiler, which allows the user to look up to 50 meters inside the seabed. This will provide the survey group with an answer as to the geological state of the seabed, meaning where there are rocks, moraine, clay and sand. 

"We also had this information from the 1995 and 1996 surveys, but it was not accurate enough. Now we get much more detailed and concise information," he added.

Also drilling continued on Tuesday, as part of which samples were taken from the seabed to also gain a vertical understanding of the seabed.

"We started exploring the wreck with a 3D sonar. We moved around the wreck, we had 16 points marked. Basically, we have now received a very detailed image of the wreck, and on Tuesday we began to examine the top of the wreck, meaning the deck house, the board of the wreck and the bottom of the wreck," Arikas said. 

The wreck of the Estonia clearly has damage from contact with the seabed, Arikas said. The wreck lies on the seabed, bottom up. The exact angle will hopefully be known today or tomorrow, he said. 

"If the ship collided with the seabed when it sank, the most severe damage is in the stern section of the ship, where, comparing with drawings, it can be seen that there are lighter structures there that are more vulnerable to damage. These damages are carried over to the central part of the ship, and in great probability the stack section has suffered a good amount of damage," he said. 

According to Arikas, surveying with a submarine robot will also begin.

"We use two solutions together -- a 3D scanner and a submarine robot. Which means that we will create a 3D digital image of the wreck, and then we will take a closer look at the identified objects with a submarine robot," he said.

"By now, we have charted the entire area around the wreck and the seabed under the route of the ship's sinking," said Arikas. "We have this picture now. There were no surprises in that. We have received confirmation of the knowledge that we had before, and rather we have been able to garner more precise data and create a 3D model. ”

As for the wreck itself, researchers knew already earlier that various objects had fallen out of the ship at the time of sinking, the exact location of which was not so well known -- now they have been identified.

The wreck itself shows multiple damages sustained in the course of the sinking.

"I don't think we can write down all the damages in great detail because of their quite large scale. But we certainly plan to pay more attention to more critical places -- especially in view of the potential damage in the starboard: where they are located, how big they are. This is the purpose of the preliminary survey," he said.

"If we find something, it will be documented and we can talk more about it," Arikas said.

"We haven't seen any great surprises so far. Rather, in the coming few days we will get more precise information to talk about in greater length," the head of the Estonian Safety Investigation Bureau added.