Boat Speed Calculator

The Boat Speed Calculator helps users estimate their boat’s hull speed, theoretical maximum speed, speed-length ratio, power-to-weight ratio, and efficiency index based on input parameters like boat length, waterline length, hull type, engine power, and boat displacement.

Use Our Boat Speed Calculator

Using the Boat Speed Calculator

This step-by-step guide will help you effectively use the Boat Speed Calculator. Follow each step carefully to input the required information and obtain accurate results.

Step 1: Input Boat Length

  1. Locate the input field labeled Boat Length (feet).
  2. Enter the length of your boat in feet in the “Enter boat length” field.
  3. The value is required and must be between 10 and 200 feet. You can input numbers with a step of 0.1 feet.

Step 2: Enter Waterline Length

  1. Find the field labeled Waterline Length (feet).
  2. Input the length at the waterline in feet in the designated area.
  3. This field is also required and must accept values ranging from 8 to 180 feet, allowing increments of 0.1 feet.

Step 3: Select Hull Type

  1. In the Hull Type section, choose the type of hull your boat has from the dropdown menu.
  2. Available options include Displacement Hull, Semi-Displacement Hull, and Planing Hull, with corresponding values of 1.34, 1.51, and 2.0.
  3. This selection is required to calculate the theoretical maximum speed of the boat.

Step 4: Input Engine Power

  1. Identify the field labeled Engine Power (HP).
  2. Enter the power of the engine in horsepower.
  3. You must provide a value between 1 and 5000 HP, allowing integer inputs.

Step 5: Enter Boat Displacement

  1. Proceed to the section labeled Boat Displacement (tons).
  2. Enter the displacement of the boat in tons.
  3. Values must be between 0.1 and 1000 tons, accepting increments of 0.1 tons.

Step 6: Review Calculated Results

After inputting all the required fields, review the following calculated results:

  • Hull Speed: Calculated as 1.34 * sqrt(waterlineLength). Displayed in knots.
  • Theoretical Maximum Speed: Derived from hullType * sqrt(waterlineLength). Displayed in knots.
  • Speed-Length Ratio: Presented as theoreticalMaxSpeed / sqrt(waterlineLength).
  • Power-to-Weight Ratio: Computed with enginePower / (displacement * 2240). Displayed in HP/lb.
  • Efficiency Index: Calculated using (theoreticalMaxSpeed * displacement) / enginePower.

By following these steps, you can ensure that you have accurately calculated various aspects of your boat’s performance based on its specifications and characteristics.