C5/2003M Boat Accident Offshore Pärnu 8.6.2003 and Five Other Boat Accidents
This accident investigation report is composed of three parts. The first part deals with sinking of a Sun 33 -type motor boat offshore Pärnu 8.6.2003. The second part includes short presentations of five boat accidents where a boat started leaking without a hull damage caused for instance by a grounding or a collision. One of these boats sunk while fastened to a jetty when waves from stern started throwing in water. The third part of the report gives safety recommendations on the basis of all investigated cases.
The Sun 33 -type pleasure boat, built 1990, was on a passage from Hanko to Pärnu via Haapsalu when the accident occurred. There were two men on board. The boat called Haapsalu 7.6.2003 for refuelling and resumed her passage the same evening towards Pärnu. The boat navigated through the marked sea area between Manilaid and Kihnu islands. From the last marked gate in a position of about 64° 12,8 N 024° 13,2 E the boat turned towards the lights of Pärnu.
The sterndrive of the boat jammed in a big fishing trap at about 24.00 in a position 58° 15,2 N 024°18,8 E. The ropes jammed on the propeller stopped the engine and the two man crew was not able to get rid of the ropes by own means. The wind and 0,5-1,0m high waves from the stern filled the boat by water and she sank at about 01.50, in the above mentioned position, despite of attempts to empty the boat. The two men had to abandon the boat. The coast guard from Pärnu rescued the men 8.6.2003 at 03.27.
The accident was caused by the boat jamming in a faulty marked fishing trap, and the boat having a low freeboard at stern and not watertight hatches and skin fittings. Waves could flood the cockpit through a gate at the transom and the not watertight engine space hatches let the water into the engine space.
Also one of the five other accidents, considered shortly in the report, was caused by waves flooding the cockpit through a gate at the transom and the water flowing into the engine space through the not watertight hatches. Hits by waves had detached the door at the transom gate, due to which the freeboard at stern decreased significantly.
The accident investigation commission recommends that the water tightness and freeboard requirements of sterndrive cabin boats at stern, at stern cockpit and at the door from cockpit to cabin should be checked. It is also recommended that these items should be part of boat owners’ training and part of the voluntary boat inspection.
The other four flooding cases investigated occurred due to breaking or corrosion of sea water piping or seacocks. On the basis of these cases, the accident investigation commission recommends that the endurance of critical parts exposed to corrosion or other ageing should be evaluated and a recommendation should be given for their renewal time.
In addition, the accident investigation commission recommends that the navigation training given to boat owners should also emphasise the importance of route planning and finding out the special characteristics of the passage sea areas, and the importance of taking into account special situations.