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Boat Max Speed Calculator

Max Speed Formula:

\[ S = C \times \sqrt{\frac{P}{D}} \]

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1. What is a Boat Max Speed Calculator?

Definition: This calculator estimates the theoretical maximum speed of a displacement hull boat based on its power-to-weight ratio.

Purpose: It helps boat owners, designers, and marine enthusiasts understand the speed potential of a vessel given its specifications.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ S = C \times \sqrt{\frac{P}{D}} \]

Where:

Explanation: The formula calculates speed based on the square root of the power-to-weight ratio, modified by the hull type constant.

3. Importance of Speed Calculation

Details: Understanding maximum speed helps in boat design, engine selection, fuel efficiency planning, and performance expectations.

4. Using the Calculator

Tips: Enter the hull constant (default 1.34), engine horsepower, and boat displacement in pounds. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical hull speed constant?
A: 1.34 for displacement hulls, 1.1-1.2 for semi-displacement, and lower for planing hulls.

Q2: How accurate is this calculation?
A: It provides theoretical maximum; actual speed depends on hull design, sea conditions, and load.

Q3: Can I use this for planing hulls?
A: This formula works best for displacement hulls. Planing hulls have different speed characteristics.

Q4: Where do I find boat displacement?
A: Check manufacturer specs or calculate as boat weight plus fuel, water, and load.

Q5: Why square root in the formula?
A: Water resistance increases with speed, so doubling power doesn't double speed.

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