Page 24: of Maritime Reporter Magazine (November 2004)

Naval Architecture & Marine Engineering "The vessel involved in that initial incident is a fairly typical containership, which means that what happened to it could happen to a lot of vessels," he says. In fact, the two years of intense study that Belenky has devoted to the subject have revealed that almost all containerships, under certain conditions, are vulnerable to parametric roll.

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Vadim Belenky, Ph.D., Engineer, Product

Research & Development tests from which we can develop a series of diagrams that will define what combi- nations of speed and sea state for given load conditions might be dangerous," he says.

Armed with such information, and, say, meteorological data from weather services, the navigating officer could, for example, determine the direction and intensity of a storm, and thus avoid dan- gerous course and speed combinations. "However, many things happen to a ship in a storm; parametric roll is just one of them," Belenky says. "Sometimes, for example, by turning into a quartering sea you reduce your control of the ves- sel, or by changing speed encounter heavier slamming that can damage the bow. The safety of the ship depends on decisions from the bridge. With our product, we help the navigating officer make a truly informed decision."

Additional products presently in vari- ous phases of development include para- metric roll advisory diagrams and a computer-based early warning system that, drawing on weather data and ship operations and navigational information, will alert the Master to potential trouble ahead. "In recognition of designers' efforts to deal with the problem, option- al class notations have been created for measures taken against parametric roll," says Belenky. "Because it is original work, many questions will arise as the industry absorbs the technology. In anticipation, we have developed the sup- port system to answer user questions and help with its application," he says. "It is, after all, the first time anyone can say to the industry regarding parametric roll, we understand the problem, and we have a solution."

This article was reprinted, with permis- sion, from ABS Surveyor magazine.

Maritime Reporter & Engineering News