While most of the marine weather data are in the public domain and free, there are also commercial services that provide specialized weather services on a subscription or fee basis. Captains Jon Harrison and Mark Remijan demonstrated this type of capability when I visited them on board APL China. They have access (via satellite and e-mail) to the latest NOAA and other weather reports to enable them to plot their own routes across the Pacific Ocean, or they can use a weather routing service. Harrison and Remijan said that generally they do their own routing using a program developed by Dr. Henry Chen. The program is very sophisticated and enables the ship master to program acceptance criteria for a route—that is, beam seas no higher than 5 meters, head seas no greater than 6 meters, no rolling greater than 20 degrees, no tropical storm approach (at 35-knot wind speed contour) closer than 50 nautical miles, etc. The program then takes the latest weather data and the ship’s parameters and computes a route that satisfies the input criteria or, if this is impossible, reports “no solution.” Different routes can be evaluated by simulating against forecast weather conditions.

Subsequently, I visited Dr. Chen, the president of Ocean Systems, Inc., at his office in Alameda, California. He demonstrated how a shipboard computer would download forecast current, wind, and wave information for an ocean area of interest. The program he developed is called Vessel Optimization and Safety System (VOSS). A unique feature is that it has the ship response characteristics (such as fuel consumption versus speed, roll and pitch periods, etc.) generated for the ship’s actual loading condition (drafts and GM) and stored in memory. The ship’s master can input safe operating envelope parameters unique to the vessel. These can include such parameters as maximum wave, maximum wind speed, maximum roll angle, number of bow slams per hour, number of times green water hits on the deck per hour, and other conditions. With this information, the master can select a destination and the program will define the optimum route that avoids exceeding the safe operating envelope and minimizes the fuel consumption for the desired arrival time. Alternate routes can be evaluated in terms of total fuel consumption, average speed, and estimated time en route so the master can evaluate the consequences of one versus another. Glo-

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