Distance Calculator For Flights

Great Circle Distance Formula:

\[ Distance = 2 \times R \times \arcsin\left(\sqrt{\sin²(\Delta\varphi/2) + \cos \varphi_1 \cos \varphi_2 \sin²(\Delta\lambda/2)}\right) \]

Latitude 1:

degrees

Longitude 1:

degrees

Latitude 2:

degrees

Longitude 2:

degrees

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. For flight planning, it represents the most efficient route between two airports, following the curvature of the Earth rather than a straight line on a flat map.

2. How Does the Calculator Work?

The calculator uses the Haversine formula:

\[ Distance = 2 \times R \times \arcsin\left(\sqrt{\sin²(\Delta\varphi/2) + \cos \varphi_1 \cos \varphi_2 \sin²(\Delta\lambda/2)}\right) \]

Where:

\( R \) — Earth's radius (6371 km)
\( \varphi_1, \varphi_2 \) — Latitude of points 1 and 2 in radians
\( \lambda_1, \lambda_2 \) — Longitude of points 1 and 2 in radians
\( \Delta\varphi \) — Difference in latitude
\( \Delta\lambda \) — 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 Great Circle Distance

Details: Great circle routes are essential for aviation and maritime navigation as they represent the shortest path between two points on Earth's surface, saving time, fuel, and costs for long-distance travel.

4. Using the Calculator

Tips: Enter coordinates in decimal degrees format. Latitude ranges from -90° (South) to +90° (North). Longitude ranges from -180° (West) to +180° (East). Ensure all values are within valid ranges.

5. Frequently Asked Questions (FAQ)

Q1: Why is great circle distance shorter than straight line on a map?
A: Maps are 2D projections of a 3D sphere, which distorts distances. Great circle routes follow Earth's curvature for the true shortest path.

Q2: What is the typical accuracy of this calculation?
A: The Haversine formula provides accuracy within 0.5% for most practical purposes, assuming a spherical Earth model.

Q3: Can I use this for driving distances?
A: No, this calculates straight-line distance. Driving distances follow roads and terrain, which are always longer than great circle distance.

Q4: How do I convert degrees to decimal format?
A: Decimal degrees = degrees + (minutes/60) + (seconds/3600). For example, 40°45'30" = 40 + 45/60 + 30/3600 = 40.7583°.

Q5: Why use 6371 km for Earth's radius?
A: This is the mean radius of Earth. For higher precision, you could use 6378.137 km (equatorial) or 6356.752 km (polar), but 6371 km is standard for most calculations.