What is the effect of squat on a vessel?

• A. Reduces stability
• B. Increases ship speed
• C. Causes an increase in draft
• D. Decreases under keel clearance

Answer: (C)

The effect of squat on a vessel primarily involves changes to its draft as it moves through the water. When a ship, particularly a larger vessel, moves at a speed through shallow water, the water flow beneath the hull can create a negative pressure area, leading to a phenomenon known as squat. This effect causes the vessel to sink further into the water, resulting in an increase in draft.

As a result, the ship displaces more water, and the submerged part of the vessel, known as the draft, is greater than it would be at rest. This increased draft must be considered during navigation in shallow waters to avoid grounding or other navigational hazards. Proper understanding of squat is crucial for safe vessel operation, especially when maneuvering in areas with limited under keel clearance. Thus, recognizing that squat leads to an increase in draft is essential for effective maritime operations.