The decrease in water level near the quarter of the vessel due to screw suction is known as what?

• A. Bank Cushion
• B. Bank Effect
• C. Bank Suction
• D. Venturi Effect

Answer: (C)

The phenomenon where there is a decrease in water level near the quarter of the vessel due to screw suction is referred to as Bank Suction. This occurs as a result of the ship's propeller drawing water away from the surrounding area as it operates. When a vessel moves forward, the rotating screws create a low-pressure zone, leading to a drop in water level near the hull. This effect can be particularly pronounced when the ship is close to the shoreline or in narrow channels where the boundaries can influence water movement.

Bank Suction is an important consideration in naval operations, especially regarding maneuvering in confined waters, as it can influence the vessel's draft and stability. Understanding this concept helps in ensuring safe navigation and maneuverability of the vessel in various maritime environments.