Distance By Air Calculator

Great Circle Distance Formula:

\[ Distance = 2R \arcsin\left(\sqrt{\sin^2\left(\frac{\Delta lat}{2}\right) + \cos(lat_1) \cos(lat_2) \sin^2\left(\frac{\Delta lon}{2}\right)}\right) \]

Latitude Point 1:

degrees

Longitude Point 1:

degrees

Latitude Point 2:

degrees

Longitude Point 2:

degrees

Airline 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. For Earth, this represents the airline distance between any two locations, following the curvature of the planet rather than a straight line through the Earth.

2. How Does the Calculator Work?

The calculator uses the Haversine formula:

\[ Distance = 2R \arcsin\left(\sqrt{\sin^2\left(\frac{\Delta lat}{2}\right) + \cos(lat_1) \cos(lat_2) \sin^2\left(\frac{\Delta lon}{2}\right)}\right) \]

Where:

\( R \) — Earth's radius (6371 km)
\( lat_1, lon_1 \) — Latitude and longitude of first point
\( lat_2, lon_2 \) — Latitude and longitude of second point
\( \Delta lat \) — Difference in latitude
\( \Delta lon \) — Difference in longitude

Explanation: The formula calculates the central angle between two points and multiplies by Earth's radius to get the great circle distance.

3. Importance of Airline Distance Calculation

Details: Great circle distance is essential for aviation navigation, flight planning, maritime navigation, and any application requiring the shortest path between two points on Earth's surface.

4. Using the Calculator

Tips: Enter latitude and longitude coordinates in decimal degrees. Latitude ranges from -90° (South) to 90° (North), longitude from -180° (West) to 180° (East). Use positive values for North and East, negative for South and West.

5. Frequently Asked Questions (FAQ)

Q1: Why use great circle distance instead of straight line?
A: Great circle distance accounts for Earth's curvature and represents the actual shortest path between two points on a sphere.

Q2: How accurate is this calculation?
A: Very accurate for most practical purposes. The formula assumes Earth is a perfect sphere, while in reality it's slightly oblate (flattened at poles).

Q3: Can I use this for driving distance?
A: No, this calculates airline distance. Driving distance follows roads and terrain, which is always longer than the great circle distance.

Q4: What's the maximum distance I can calculate?
A: The maximum great circle distance on Earth is approximately 20,000 km (half the circumference).

Q5: How do I convert coordinates to decimal degrees?
A: For coordinates in degrees-minutes-seconds (DMS), use: Decimal = degrees + minutes/60 + seconds/3600.