Which factors influence the swing circle radius for a vessel at anchor?

• A. The vessel's length overall and the distance from the bow to the pivot point
• B. The weather conditions
• C. The color of the anchor chain
• D. The time of day

Answer: (A)

When a vessel is at anchor, it can swing around the anchor point, tracing a circle whose size is set by geometry rather than mood or color. The swing circle radius reflects how far the hull can reach from the anchor as it rotates, which depends on how much rode you have out and how the boat’s hull sits relative to the anchor. The two geometric factors that determine that radius are the vessel’s length overall and the distance from the bow to the point where the rode is attached (the pivot point). A longer boat or a greater offset between the bow and the pivot point means the hull can sweep a larger circle around the anchor. Weather conditions will influence where you actually end up within that circle, but they don’t change the circle’s size itself. The color of the anchor chain or the time of day don’t affect the achievable swing radius.