Which method is least effective for verifying the vessel’s position on ECDIS during coastal navigation?

Which method is least effective for verifying the vessel’s position on ECDIS during coastal navigation?

• A. Using GPS
• B. Switching the ECDIS into DR mode
• C. Referencing radar data
• D. Visual landmarks

Answer: (B)

Switching the ECDIS into DR (Dead Reckoning) mode is the least effective method for verifying the vessel’s position during coastal navigation because DR mode relies solely on the vessel's last known position, which is often derived from previous position fixes. This method calculates the vessel's current position based on speed, course, and time since the last position fix, without taking into account any external influences that could affect the vessel's actual position, such as currents or wind. In coastal navigation, where precision is crucial due to the proximity to hazards and landmarks, relying exclusively on dead reckoning can be misleading. This method does not incorporate real-time position updates from navigational aids or environmental conditions that can alter the vessel's actual path. In contrast, using GPS provides accurate and real-time positioning data, referencing radar data allows for guidance and verification against coastal features, and visual landmarks can help to verify the vessel's position against known points on the chart. All these methods offer more reliable checks against a vessel's actual position, especially in the dynamic environment of coastal waters.

Switching the ECDIS into DR (Dead Reckoning) mode is the least effective method for verifying the vessel’s position during coastal navigation because DR mode relies solely on the vessel's last known position, which is often derived from previous position fixes. This method calculates the vessel's current position based on speed, course, and time since the last position fix, without taking into account any external influences that could affect the vessel's actual position, such as currents or wind.

In coastal navigation, where precision is crucial due to the proximity to hazards and landmarks, relying exclusively on dead reckoning can be misleading. This method does not incorporate real-time position updates from navigational aids or environmental conditions that can alter the vessel's actual path.

In contrast, using GPS provides accurate and real-time positioning data, referencing radar data allows for guidance and verification against coastal features, and visual landmarks can help to verify the vessel's position against known points on the chart. All these methods offer more reliable checks against a vessel's actual position, especially in the dynamic environment of coastal waters.