Older reports

Investigations made before the establishment of The Accident Investigation Board (1986-1995)


Investigation report on the collision between MT TEBOSTAR and the fishing vessel LADUSHKIN SW of Gotland on Sept.5,1989

South of Gotland, at about 23.40 local time on Tuesday, 5 September 1989, the Finnish tanker Tebostar collided with the Soviet fishing vessel Ladushkin, which sank. In the accident all 15 Soviet seamen aboard the Ladushkin lost their lives.

Download here the investigation report (abridged version) (pdf, 2.12 Mt)


The Grounding of the M/S SILJA EUROPA at Furusund in the Stockholm Archipelago on 13 January 1995

The Finnish passenger/car ferry MS SILJA EUROPA ran aground at Furusund in the Stockholm archipelago on 13 January 1995 at 4.35 A.M. Finnish time. The vessel managed to refloat on her own power at 5.07 A.M. She received only minor damage to her bow bulb. There were no injuries or environmental damage.

Before the grounding occurred, the bridge staff observed that the vessel was turning too much to starboard. Control was transferred from automatic to manual, but the vessel didn’t respond to the rudder. Attempts were made to switch off the SPEEDPILOT automatic speed control system apparently in two different ways and it was also checked that control had not been transferred to the engine room. The vessel remained unsteerable. Finally she ran aground immediately to the right of the Furusundsskaten beacon.

The sequence of events leading to the grounding began when the position sensor of the vessel was transferred, at 04.22, from one DGPS receiver to another. However, the speed sensor that gave the speed data to the SPEEDPILOT system was not switched at the same time to the other DGPS receiver, and instead remained in the previous receiver. In this connection the SPEEDPILOT went over automatically to the MANUAL SPEED control mode. The SPEEDPILOT continuously received information indicating a speed of 17,62 knots, which was the most recent information recorded in the system before going over to the second DGPS receiver. The SPEEDPILOT reacted to this by giving a SP SPEED FAULT alarm, but the vessel had not been supplied with a list of alarms which would have indicated what this alarm was about, and what steps should be taken.

When the vessel approached the Furusund narrows where the speed limit was eight knots, the SPEEDPILOT began to automatically reduce speed by lowering the pitches of the propellers. The SPEEDPILOT no longer received up-to-date information regarding speed from the speed sensor, since this had gone over to the MANUAL SPEED mode. Nonetheless the equipment continued to function automatically as if the speed sensor would have continued to input the same speed of 17,62 knots. The result was that the propeller pitch decreased to zero, and the vessel was no longer steerable. Such performance by the equipment can be considered a design error.

After the grounding occurred, the SPEEDPILOT was found to be still engaged. Efforts were made to switch it off in the same way as before the grounding, and also with the BYPASS switch, which should disconnect power to the SPEEDPILOT system. However, the system remained on. The SPEEDPILOT was overridden when control was transferred to the engine room. When control was transferred again to the bridge, the SPEEDPILOT continued to be in the engaged mode.

The bridge regained control by pressing the KaMeWa BACKUP push-button and thus switching to emergency manual control. This control system overrides the SPEEDPILOT, so the SPEEDPILOT can be switched on while it is used. The vessel was floated off the rocks with the BACKUP emergency control system.

The grounding could not be avoided by using the rudder since the propeller pitch had decreased to such an extent that the vessel was no longer manouverable. A malfunction led to a failure in switching the SPEEDPILOT off. The malfunction was probably a result of the engine interface card 1 becoming detached from the electronics frame. In simulations, the detachment of this card has been found to have the same effects as those that occurred in the accident. This is the only possible malfunction that has been identified by the investigation commission. The failure of components on the card could also result in the same fault situation. During the investigation however nothing has appeared that would suggest that there were faulty components on the card. Furthermore, a program failure also cannot be ruled out entirely.

Lack of familiarity with the emergency systems made it even more difficult for the officers on the watch to bring the situation under control before the grounding. Control was not switched to the emergency manual system by the BACKUP push button. The SPEEDPILOT could have been overridden with the BY-PASS switch. This switch, which was installed separately afterwards on this vessel and poorly located ergonomically, was not used.

The officers of the watch did not have the ability to use the emergency systems, due to inadequate emergency drilling and because of omissions in training.

The Grounding of M/S SILJA EUROPA at Furusund in the Stockholm Archipelago on 13 January 1995 (pdf, 1.02 Mt)