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?tanker. Eniram started with an assump- tion that there would be limited scope for real performance improvements on a large commercial vessel of this type through trim optimization, due to their relative ?box? shape and the large varia- tion in their drafts according to whether they are in laden, partly laden or ballast condition. Previously, the complexity of large tanker operations has created access is- sues on VLCCs for the purpose of site surveys, technical attendance, and in- stalling measurement equipment. Off- shore operations can cause additional hurdles around immigration and custom clearance. A comparative limitation in satellite broadband capabilities on some tankers in comparison to other types of vessels adds to the challenges of getting the necessary data from the vessel to our data processing center without delays. Eniram patiently overcame these is- sues and, using its proprietary technol-ogy, embarked on extensive monitoring of all internal and external conditions af- fecting the given vessel over a 450-day study period during its lengthy voyage across the world?s oceans. To ensure the research was robust, Eniram integrated its technology with engine automation and bridge systems. Attitude sensors were also installed, to collect informa-tion on dynamic movements of the ves- sel including trim, list, accelerations and decelerations.Isolating the different inß uencers of performance Eniram was able to analyze the amount of energy consumed by differ- ent factors (trim, sea state, wind, squat, hull and propeller fouling, etc). Model-ing all the dynamic factors for various ?To establish the broader potential of trim optimization across commercial vessels, particularly VLCCs, Eniram set out to investigate in detail the impact of dynamic trimming on propulsion power consumption on of a 320,000+ DWT tanker. www.maritimeprofessional.com | Maritime Professional | 57