Understanding Great Circle Routes
When you look at a flight path on a flat map, it often appears as a curved line. This can be counter-intuitive, as we're used to straight lines being the shortest distance between two points. However, because the Earth is a sphere (roughly), the shortest path between any two points on its surface is an arc known as a Great Circle.
Orb Vector visualizes these true trajectories in 3D space, showing you the actual path an aircraft would take to minimize travel distance. This is why flights from New York to London, for example, appear to arc northwards over Newfoundland and the Atlantic Ocean.
Frequently Asked Questions
- What is a Great Circle?
- A Great Circle is the intersection of a sphere and a plane that passes through the sphere's center. It represents the largest possible circle that can be drawn on a sphere and defines the shortest path between two points on the surface.
- Why do flight paths look curved on 2D maps?
- Most 2D maps use the Mercator projection, which distorts size and shape as you move away from the equator. A straight line on a Mercator map (a rhumb line) is actually a longer path than the curved Great Circle route. Pilots fly the Great Circle route to save fuel and time.
- How accurate are the distances?
- Orb Vector calculates distances using the Haversine formula, which accounts for the Earth's curvature. While the Earth is not a perfect sphere (it's an oblate spheroid), the error margin is negligible for general flight planning and visualization purposes, typically within 0.5%.
- Can I measure multi-stop routes?
- Yes! You can chain multiple airports together to create a complex itinerary. The tool will calculate the distance for each leg of the journey as well as the total cumulative distance.
- How is flight time estimated?
- Our flight time estimator uses a standard cruising speed of 900 km/h (approx 485 knots) and adds a 30-minute buffer for takeoff and landing per leg. Crucially, it also accounts for the Jet Stream: eastbound flights are calculated as ~15% faster due to tailwinds, while westbound flights are slower due to headwinds.
- What are the "Discover Routes"?
- We've curated a selection of extreme and interesting aviation routes, such as the world's longest flight (Singapore to JFK) and the "Island Hopper" across the Pacific. Use the "Discover Routes" menu to instantly visualize these famous trajectories.