Measurements during SWATH ship sea trials

Abstract

A new ship must undergo a rigorous set of sea trials to receive final certification. The sea trials program measures the vessel's performance against its design specifications and code requirements. The performance evaluation includes the ship's powering requirements (ability to achieve and maintain its design speed in a variety of conditions), fuel economy, maneuvering capabilities (safe and efficient handling), and seakeeping ability (stability and comfort in a seaway). One of my tasks over the past few years has been to measure a ship's performance during sea trials. These tests require temporary measurement equipment not usually contained in the ship's built-in instrumentation suite. This article describes that temporary measurement equipment and its operation. The hydrodynamics of a SWATH ferry such as the Cloud X are extremely complex and subject to many variables. The sea trials measurement system on-board has already provided valuable insight into the variables affecting the performance of the Cloud X. The measurement system is simple, easy to reconfigure, and allows for expansion as needed. New channels of nearly any type can be easily integrated into the measurement system on the spot.