C4/2004M Passenger Vessel SUOMENLINNA II, Grounding in Helsinki on 5.7.2004 and Seven Other Incidents

On 5.7.2004, SUOMENLINNA II, the new vessel operating the 3 km long ferry connection between Kauppatori and Suomenlinna in Helsinki, lost its manoeuvrability and had a light bottom contact. The Accident Investigation Board initiated an investigation, during which the vessel was involved in seven other incidents. All of these incidents were addressed in the investigation.

Technical faults experienced on 5.7.2004 and 12.8.2004. On both occasions, the vessel suffered a blackout and loss of manoeuvrability. On the first occasion, this resulted in a bottom contact off the shore of the island Valkosaari. On the second occasion, the vessel collided with a bridge in Suomenlinna. These situations were caused by malfunction of the fuel system and incorrect installation of electrical cables. In both cases, the situation was compounded by faults in the diesel-electric propulsion system settings, resulting in total failure of the electrical system. There was no personal injury, and other damage was minor.

Collisions with quay in Suomenlinna on 5.10.2004 and 7.10.2004 and in Kauppatori on 17.12.2004. All three quay collisions resulted from the crew neglecting to turn off the autopilot. The system allowed turning the control levers while the autopilot was turned on and did not warn the skipper even though turning the levers had in reality no effect on the position of the rudder propeller. A total of five persons were slightly injured in the collisions. In addition, the Suomenlinna ramp was damaged beyond repair, and the latest collision made a hole in the vessel above the waterline.

Momentary losses of control on 13.12.2004, 15.12.2004, and 28.5.2005. In two cases, the loss of control was caused by abandoning an attempt to overtake another vessel due to traffic conditions. When the skipper reduced engine power in order to allow the SUOMENLINNA II to slow down, it began to turn. This happened because, after engine power was reduced, no course-keeping forces existed. One of the loss-of-control situations began after a turn, when the skipper’s attempt to manoeuvre had no effect. The skipper then turned the control lever more, causing the vessel to quickly turn too much. The essential element in all three cases was the difficult manoeuvring of the vessel, mainly related to its lack of directional stability. In all cases, the skippers had all steering functions available, and they still had means to prevent potential accidents, regardless of the loss of control. There was no damage.

Summary. With the exception of one loss-of-control situation, all of the incidents involved risk factors that could be expected to occur in a new-building project. The technical problems were not identified during the design and construction, before the vessel was taken into use. The quay collisions involved the autopilot system, when related risks had not been anticipated. However, the loss-of-control situations were caused by the fact that the parties were surprised by the vessel’s properties and how difficult it was to handle, even though they could have prepared for these in advance.

As a contributing factor, the shipowner was inexperienced with newbuilding projects especially consisting of new technology. The Danish trading house acting as supplier, and the Polish shipyard were also unfamiliar with this kind of projects and it contributed to the first two incidents. The inexperience of the parties was not taken into account by the supervising authorities, who could have predicted risks of the type that occurred. The problems with the fuel system were caused by the original system design being risky from the operational standpoint. Better supervision could have affected the faulty cable installation and mistakes in the settings of the automation. For example, sufficient professional skills on the part of the electricians in the installation work should have been ensured. In addition, the integration of the machinery and propulsion automation should have been planned and performed better. When the vessel was taken into use, the training provided for the SUOMENLINNA II skippers was insufficient and too focused on normal operations. For example, it should have included more training involving exceptional situations.

Ships are normally built in small series. Accordingly, most ships can be considered prototypes. This is particularly true of the SUOMENLINNA II, because vessels of this size have never before been built equipped with electric-powered rudder propeller systems at both ends. Utilising new technology and new vessel types promotes progress in the marine technologies and provides new kinds of possibilities and characteristics for the vessel in question. On the other hand, such solutions increase the risks and require high-quality operations of all parties.

No recommendations are made on the basis of the investigation. The investigation report itself attempts to provide information on how demanding such new construction projects can be and what kinds of risks should be taken into account.

C4/2004M Report (pdf, 1.55 Mt)

Published 13.5.2004