1. What is LWL (Length Waterline)?

The LWL (Length Waterline) is the length of a boat from the point where the hull touches the water at the bow to the point where it touches the water at the stern. It's a crucial measurement in naval architecture and boat design as it affects speed and performance.

2. How Does the Calculator Work?

The calculator uses the LWL formula:

Where:

• \( measured\_length \) — The measured length of the boat hull (ft)
• \( design\_factor \) — A dimensionless factor based on hull design (typically 0.9-1.1)

Explanation: The design factor accounts for the specific characteristics of the hull design that affect where the waterline falls.

3. Importance of LWL Calculation

Details: LWL is critical for determining a boat's speed potential (hull speed), stability, and displacement. It's used in performance predictions and classification rules.

4. Using the Calculator

Tips: Enter the measured length of the hull in feet and the appropriate design factor. The design factor varies based on hull type - consult naval architecture references for specific values.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between LOA and LWL?
A: LOA (Length Overall) is the maximum length of the boat including overhangs, while LWL is only the length touching the water.

Q2: How does LWL affect boat performance?
A: Longer LWL generally means higher potential speed (hull speed = 1.34 x √LWL) and better sailing performance.

Q3: What's a typical design factor?
A: For most displacement hulls, it ranges from 0.9 to 1.1. Racing boats often have higher factors than cruising boats.

Q4: Does LWL change with loading?
A: Yes, LWL increases as a boat is loaded more heavily and sits lower in the water.

Q5: Why is LWL important for sailboats?
A: It affects righting moment, sail carrying capacity, and speed potential - key factors in sailboat performance.