Improving Safety of Ships at Sea

Applied Weather Technology (AWT) announced that its Route Optimization Service, used by ships to help identify the most efficient routes to their destinations, now includes technology that helps AWT's Route Analysts warn ships at sea of the potential for resonance, a physics phenomenon that can cause ships to severely roll and lead to crew injury and cargo loss. The severe motion alerts /resonance alerts are based not only on the weather, but also on the vessels' size, draft, stability, heading and wave conditions.

Numerous ships each year experience severe rolling and/or crew injuries and/or cargo loss. One of the reasons why a ship might suddenly and severely roll is due to resonance, when the roll period of the vessel and the wave period relative to the vessel are nearly the same. When this happens, a vessel can go from slight or moderate rolling, to dangerous 35+ degree rolls very quickly. Violent rolling can cause cargo to shift or break loose, which can change the stability of the vessel and further endanger the cargo, vessel and crew.

Previously the industry standard was to only intuitively take into account the stability of a specific vessel when analyzing how a ship might react to certain wave or weather conditions. This new service analyzes criteria specific to the vessel in addition to the wave conditions to anticipate the motions that each vessel might experience that could lead to resonance and severe rolling. Different vessels going through the same weather could experience dramatically different motions, depending on factors such as the ship's speed, length, beam, draft or stability.

According to the company, AWT monitors approximately 1500 vessels and fields between 10-30 resonance alerts each day, depending on the time of year and weather patterns. AWT evaluates each alert and sends a course change and/or a speed recommendation to the ship in the cases when the company believes the vessel may experience a problem. The alerts show where severe motions are most likely to occur at a specific time along the vessel's route, and indicate which headings and/or speeds could be used to avoid these areas, thereby minimizing the potential of heavy weather damage. These types of alarms allow AWT to find the most efficient route while helping to keep the crew, vessel and cargo safe.