Stability:
Case Study 4
Vessel Type: Dry Cargo
Trading Area: Southeast Asia
Case No: 42200
Incident:
A Feeder Container Vessel had completed cargo operations at one berth and was in the
process of shifting to a second berth. A harbour tug commenced pushing the vessel towards
the berth when the member’s vessel began to heel over. When heeled over to approximately
10-15 degrees, containers began to fall off the vessel; the tug stopped pushing, and this
action in conjunction with the loss of containers enabled the vessel to return to near upright.
Observations:
The subsequent investigations showed that poor operational practices were allowed to take
place onboard with very little regard to the safety of the vessel. The centre of gravity (KG) of
the vessel was determined to be well above the maximum permitted and no account had been taken of the numerous free surfaces in the ballast tanks. To make matters worse, it was
calculated that the vessel was in fact 400t over loaded, which resulted in her having a
freeboard of approximately 30cms less than the minimum permitted.
These factors combined to result in a drastic reduction of transverse stability which was
insufficient to withstand the forces created by the pushing tug. Ironically, the top tiers of
containers had not been secured but this allowed the containers to fall off and the vessel
returned to the upright. One of the contributing factors to the overloading was the under
declaration of the container weights by the shipper. This case highlights the need to monitor
the vessel’s condition at all times. By observing the drafts, the overloading would have been
noted at an early stage and the vessel’s lack of adequate stability detected.
Financial Cost:
The total cost of this claim was in excess of US$660 000; a great deal of this was accounted
for in recovering containers that sank in the approach channel to the berth.
