On the performance of a large high-speed trimaran

Abstract

Trials and measurements conducted on an aluminium 127 metre long trimaran fast ferry are presented, covering the period of builder’s trials, delivery voyage, and during operation. Measurements were taken of strains at strategic locations in the structure, together with accelerations in all principal directions and the wave environment. Strain correlation factors were derived to be applied to the Finite Element models for future trimaran structural design. Comparisons are made between the trimaran and a range of equivalent catamarans, and the superior speed of the trimaran over the catamaran in both calm water and in waves is demonstrated. The measured speed loss in waves for the trimaran is also compared against a numerical prediction. Improved roll and pitch characteristics are presented for the trimaran and generally improved levels of comfort, with a demonstrated 50% reduction in passenger sea sickness for the trimaran compared with the catamaran.

Keywords:

• Fast ships
• Trimarans
• seakeeping

Additional information

Notes on contributors

Tony Armstrong

Tonyt is Manager of R&D at Austal Ships, the leading manufacturer of high-speed aluminium craft. Tony has been involved in the design of very many large aluminium fast ferries since the first one was built 17 years ago. Austal invests heavily in R&D, particularly hydrodynamic optimisation and structural design, as well as manufacturing techniques. The design of the world’s first high-speed trimaran was the results of four years of dedicated research into improving the comfort of these types of craft.