Core Calculation Formula

The calculator uses the fundamental relationship between fuel consumption, speed, and range:

Time Aloft (Hours) = Fuel Tank Size / Engine Fuel Consumption

Estimated Range (Nautical Miles) = Time Aloft × Average Cruising Speed

Step-by-Step Calculation Process

1. Input Collection

• Fuel Tank Size (Gallons or Liters)
• Engine Fuel Consumption (GPH or LPH)
• Average Cruising Speed (Knots)
• Fuel Price per Unit ($/Gallon or $/Liter)

1. Time Calculation

• Determines how long the boat can operate on a full tank
• Formula: Time = Tank Size ÷ Consumption Rate

1. Range Calculation

• Calculates maximum distance achievable
• Formula: Range = Time × Speed
• Results displayed in Nautical Miles (NM)

1. Cost Estimation

• Calculates total fuel cost to fill the tank
• Formula: Cost = Tank Size × Fuel Price

Safety Margin Implementation

For practical boating applications, the calculator includes a 15% safety reserve:

• Safe Range = Estimated Range × 0.85
• Safe Time = Time Aloft × 0.85

This safety margin ensures you maintain adequate fuel reserves for unexpected conditions or emergencies.

Chart Visualization

The calculator provides a visual comparison between:

• Total Range (NM) – Maximum theoretical range
• Safe Range (NM) – Recommended range with 15% reserve
• Time Aloft for each scenario