Effect of Longitudinal Bulkheads on Damage Stability of Model RO/RO Ferries

The paper reports on experimental investigations which have been made on three model RO/RO ferries. One of these was based on a 1/100th scale model of the Herald of Free Enterprise ferry. The other models were modified versions of the Herald of Free Enterprise which were so modified that they did not decrease the efficient concept of the throughput of a conventional vessel. One modified model had nine longitudinal compartments, while another had six longitudinal compartments; these vessels should meet SOLAS90+50 regulations. The RO/RO ferry models with nine and six compartments had considerably better damage stability characteristics than the conventional model. The experiments were carried out on all models without the consideration of waves and wind. Small weights were placed on the model ferries, to represent motor vehicles, and water was added on the car deck. Measurements of the resulting heel angles were taken. All results were plotted on graphs and they were compared and discussed. The effect of cargo shift on the transverse damage stability of these vessels was found to be significant. The paper also contains a brief history of a few very important RO/RO ferry accidents that have taken place since the end of the Second World War.