Calculate Nautical Miles Between Ports

Haversine Formula:

\[ d = 2r \arcsin\left(\sqrt{\sin^2\left(\frac{\Delta\phi}{2}\right) + \cos\phi_1 \cos\phi_2 \sin^2\left(\frac{\Delta\lambda}{2}\right)}\right) \]

Port 1 Latitude:

Port 1 Longitude:

Port 2 Latitude:

Port 2 Longitude:

Nautical Miles Between Ports:

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1. What is the Haversine Formula?

The Haversine formula calculates the great-circle distance between two points on a sphere given their longitudes and latitudes. It's particularly useful for navigation as it provides accurate distance calculations on the Earth's surface.

2. How Does the Calculator Work?

The calculator uses the Haversine formula:

\[ d = 2r \arcsin\left(\sqrt{\sin^2\left(\frac{\Delta\phi}{2}\right) + \cos\phi_1 \cos\phi_2 \sin^2\left(\frac{\Delta\lambda}{2}\right)}\right) \]

Where:

\( d \) — Distance between the two points
\( r \) — Radius of the Earth (3440.065 nautical miles)
\( \phi_1, \phi_2 \) — Latitude of point 1 and point 2
\( \Delta\phi \) — Difference between latitudes
\( \Delta\lambda \) — Difference between longitudes

Explanation: The formula accounts for the curvature of the Earth to provide accurate distance measurements between any two points on the globe.

3. Importance of Nautical Miles Calculation

Details: Accurate distance calculation between ports is essential for voyage planning, fuel estimation, and navigation safety in maritime operations.

4. Using the Calculator

Tips: Enter coordinates in decimal degrees (e.g., 34.0522 for Los Angeles). Positive values for North/East, negative for South/West. For best accuracy, use coordinates with at least 4 decimal places.

5. Frequently Asked Questions (FAQ)

Q1: Why use nautical miles instead of kilometers or statute miles?
A: Nautical miles are based on the Earth's circumference and are the standard unit of measurement in maritime and aviation navigation.

Q2: How accurate is this calculation?
A: The Haversine formula provides good accuracy for most practical purposes, though it assumes a perfect sphere (Earth is actually an oblate spheroid).

Q3: What's the difference between great-circle and rhumb line distance?
A: Great-circle distance is the shortest path between two points on a sphere, while rhumb line maintains a constant bearing.

Q4: Can I use this for air navigation as well?
A: Yes, the same formula works for air navigation distances between airports.

Q5: How do I convert decimal degrees to degrees-minutes-seconds?
A: Multiply the decimal portion by 60 for minutes, then multiply the remaining decimal by 60 for seconds.