Weight Estimation of Superyachts

Abstract

Superyachts are expected to be perfect since the owner pays millions for them, and the worst that could happen is tilting the ship once it floats. The lightweight, including the center of gravity, is essential to know with a high degree of certainty to prevent this. However, the lightweight is already expected in an early design phase, when still a lot is uncertain. When the weight deviates from the initial estimations, it would predominantly lead to unwanted changes in speed and stability.
The objective is to research a standardized way of estimating the weight of a superyacht in different stages of the project, including validating the current, improved, and new methods and combining this in a single tool. In the design phase, at the beginning of the project, most weight items or groups are based on comparisons with another yacht. Currently, this is done based on a single ship similar to the new design. Still, a significant improvement will be to compare the new design with multiple yachts, with the possibility for the designer to choose the comparison vessels.
The margins can also be researched. Currently, only the starting margin and the production margin at the end are set, but not in between. A guideline should be provided to indicate what margin is expected during each project stage. Also, the complexity level can influence the expected margin, which can all be placed in a table for a clear overview.
The center of gravity estimation of the items is done similarly to the weights. The weight distribution of the yacht is currently not included in the weight estimations, but it will be included in the new weight estimation tool. To achieve this, besides the CoG, the length of the items also needs to be noted for the longitudinal weight distribution. With this information, distribution along the ship in the length direction can be calculated per meter. The model can be validated by comparing these early design stage estimation methods with the more detailed estimates at the end of the engineering stage.
Finally, the research question can be answered, concluding the research. The weights and centers of mass of a superyacht can be predicted in the design phase by comparing the new ship to a database of existing yachts. These estimations can indicate the calculations’ completeness and accuracy at the engineering phase. The weight list includes margins based on the project’s stage and complexity. This way, the estimations and calculation accuracy are transparent and explainable. Also, the longitudinal weight distribution is added to complete and track the center of gravity estimations. Both the design and engineering department can present their findings and estimations next to each other, resulting in a clear overview of development during the project.