Assessment of percent-time-operable of surface combatants with conventional and wave-piercing hulls

The present study concerns assessing and comparing the operability of two surface combatants with conventional and modern wave-piercing hulls. The operability is measured in terms of the percent-time-operable (PTO), based on the capability of missions in the annual operating condition by seakeeping analysis. The seakeeping criteria of the surface combatant in various missions are selected by the literature review applicable to the basic design stage. The numerical seakeeping analysis is performed to obtain ship motion spectra in seaways around the Korean peninsula and North Pacific, after corrected by comparison to the experiments in regular waves. It is found that the wave-piercing hull has higher PTO than the flared hull under a generic operation scenario owing to reduced pitch motion and low resonance frequency of roll motion, the main restraint of seakeeping performance in PTO assessment.