As several serious incidents have taken place, where car carriers have capsized as a result of inadequate stability, operators should be aware of the final cargo weight distribution.
As Gard Club informs, car carriers are on a tight schedule with quick port rotations and operate in a very different manner when compared to other vessel segments such as tankers and bulk carriers, where the cargo planning is done onboard.
On car carriers, it is the shore side that does it with no involvement of the ship’s crew, whose role is limited to ensuring that the vessel can achieve adequate stability based on the proposed pre-stowage plan, and this is typically done by adjusting the ballast onboard
Gard said.
Taking this into consideration, the biggest challenge is that the weight distribution of the cargo actually loaded onboard could differ significantly from the pre-stow plan.
In fact, these changes might not be communicated in a positive manner to the ship’s crew timely before departure from port.
Either the crew are not given a copy of the final stowage plan or if provided then there may not be enough time for the crew to check and ensure that vessel has adequate stability
The result of this miscommunication is that the ship departs with inadequate stability, having a small or negative metacentric height (GM).
To address this problem, Gard recommends the following:
- Operators should make sure that the weights of the vehicles mentioned in the stow plans are not estimates. Accurate weight declaration of the cargo should be prioritized prior to loading.
- Vessel operators should have a procedure in place to advise the vessel if there are changes to the preliminary / pre-stow cargo plan. Responsibility for communicating this would typically rest with the person in charge of tallying the cargo (plan clerk, checker or supervisor), usually appointed by the operator.
- After the cargo operations are complete, ship’s crew should be given a copy of the final stow plan with accurate weight of the cargo and stowage location. The final departure stability condition should be calculated using the final stow plan.
- The vessel should not carry out unmooring operations until the final stability calculations are complete. If this is not done, the crew should be empowered to delay the departure.
- Any concerns should be communicated to both the vessel operator and the ship owner / ISM manager and rectifications made prior to unmooring operations.