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Rudder Size Calculator

Calculate optimal rudder dimensions for steering control and performance.

Quick Samples
Try these common configurations to get started

30ft Cruising Sailboat

Balanced cruiser design

25ft Sport Fishing Boat

Fast, maneuverable powerboat

40ft Racing Yacht

High-performance spade rudder

Hull Dimensions
Enter your boat's principal dimensions
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About This Tool
The Rudder Size Calculator provides essential dimensions and parameters for designing a boat's rudder. A well-designed rudder is critical for steering control, maneuverability, and overall safety. This tool estimates the required rudder area, aspect ratio, and stock diameter based on your boat's key specifications, helping you to create a balanced and effective steering system.

Key Concepts:

Rudder Area: The total surface area of the rudder, determining its steering force.
Aspect Ratio: The ratio of the rudder's depth to its chord (width). Higher ratios are more efficient but can stall.
Rudder Stock: The shaft that the rudder pivots on; must be strong enough to handle steering loads.
Lateral Plane: The underwater profile of the hull; rudder area is calculated as a percentage of this.
Frequently Asked Questions

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