1. What is the Boat Speed Formula?

The boat speed formula estimates a vessel's speed based on its power, displacement, and a hull-specific factor. It provides a theoretical maximum speed for displacement hulls.

2. How Does the Calculator Work?

The calculator uses the boat speed formula:

Where:

• \( power \) — Engine power in horsepower (hp)
• \( displacement \) — Boat weight in pounds (lb)
• \( factor \) — Hull-specific coefficient (typically 1.34 for displacement hulls)

Explanation: The formula shows that speed increases with the square root of power-to-weight ratio, modified by hull efficiency.

3. Importance of Boat Speed Calculation

Details: Understanding potential speed helps in boat design, engine selection, and performance expectations. It's crucial for fuel planning and safety considerations.

4. Using the Calculator

Tips: Enter power in horsepower, displacement in pounds, and appropriate hull factor. Typical factors range from 1.1 to 1.5, with 1.34 being common for displacement hulls.

5. Frequently Asked Questions (FAQ)

Q1: Why is the factor important?
A: The factor accounts for hull efficiency. Different hull types (displacement, planing, semi-displacement) have different characteristic factors.

Q2: What are typical speed ranges?
A: Displacement hulls typically max at 1.34 × √(LWL in feet). Planing hulls can exceed this with sufficient power.

Q3: When does this formula not apply?
A: For planing hulls at high speeds, other factors like hull lift become significant and this formula underestimates speed.

Q4: How accurate is this calculation?
A: It provides theoretical maximum for displacement hulls. Actual speed depends on conditions, load, hull cleanliness, and other factors.

Q5: Should this be used for sailboats?
A: For sailboats under power, yes. Under sail, different formulas considering sail area and wind speed are used.