Accident Investigation Report: Bowsprite
Read our marine accident investigation report, which includes what happened, actions taken and subsequent recommendations:
During the night of 4/5 December 1988 the suction dredger BOWSPRITE was bound from a position off Nieuwpoort, Belgium, towards the River Thames with a cargo of marine aggregate. Just before midnight, when about 15 miles NNW of Nieuwpoort, the bottom shell fractured. The weather was severe, with strong gale (force 9) westerly winds and very rough seas. The fracture occurred at about midships (half length) and quickly developed to the extent that the ship broke into two, the forward part sinking and the aft part remaining afloat.
high stresses were generated in the region of frames 66 to 68 in the ship’s bottom shell as a result of the motions of the ship when heading fully loaded into very severe weather conditions. It has not been possible to quantify these stresses due to the complexity of the local concentration and interactive stresses caused by the geometry of the structure, the intersection of welds and the shell plate wastage and pitting in the areas concerned.
the high stresses resulted in hull plate fractures being initiated and propagated in the bottom shell
the primary source of initial fracture occurred in the bottom shell starboard in way of frames nos 66 and 67. and spread rapidly to the port side. Weakened by this fracturing, the ship broke completely in two.
A number of recommendations have been made as a result of our investigation.
This report was published on 2 May 1991.
Published 23 January 2015