Great Circle Flight Distance Calculator

Great Circle Distance Formula:

\[ d = 2 R \arcsin\left(\sqrt{\sin²\left(\frac{lat2-lat1}{2}\right) + \cos(lat1) \cos(lat2) \sin²\left(\frac{lon2-lon1}{2}\right)}\right) \]

Latitude of Point 1:

degrees

Longitude of Point 1:

degrees

Latitude of Point 2:

degrees

Longitude of Point 2:

degrees

Distance Unit:

Great Circle Distance:

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1. What is Great Circle Distance?

The great-circle distance is the shortest distance between two points on the surface of a sphere, measured along the surface of the sphere. For Earth, this represents the shortest flight path between two locations.

2. How Does the Calculator Work?

The calculator uses the Haversine formula:

\[ d = 2 R \arcsin\left(\sqrt{\sin²\left(\frac{lat2-lat1}{2}\right) + \cos(lat1) \cos(lat2) \sin²\left(\frac{lon2-lon1}{2}\right)}\right) \]

Where:

\( d \) — Distance between points
\( R \) — Earth's radius (6371 km)
\( lat1, lat2 \) — Latitude of points 1 and 2 (in radians)
\( lon1, lon2 \) — Longitude of points 1 and 2 (in radians)

Explanation: The formula calculates the central angle between two points and converts it to distance using Earth's radius.

3. Importance of Great Circle Distance

Details: Great circle distance is crucial for aviation and navigation as it represents the shortest path between two points on Earth's surface, saving time and fuel.

4. Using the Calculator

Tips: Enter coordinates in decimal degrees (e.g., 40.7128 for New York latitude). Positive values for North/East, negative for South/West. Select desired distance unit.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: Very accurate for spherical Earth model. Actual Earth is an oblate spheroid, but difference is typically less than 0.5%.

Q2: Why not use straight-line distance?
A: Straight-line distance would go through Earth. Great circle distance follows Earth's curvature.

Q3: What's the maximum possible distance?
A: Half Earth's circumference (~20,037.5 km or ~12,450.8 miles).

Q4: Does this account for altitude differences?
A: No, it assumes both points are at sea level. Altitude differences have negligible effect at Earth's scale.

Q5: Can I use this for other planets?
A: Yes, if you adjust the radius (R) parameter for the specific celestial body.