Given the latitude and longitude of two points on the Earth's surface, UltimaCalc can calculate the Great Circle and Rhumb Line routes between these points. Please note that any route calculated by UltimaCalc is meant for demonstration purposes only, and should not be solely relied upon for real-world navigation.

The following image shows two routes from New York's JFK airport to London's Heathrow airport, based on a Great Circle (the shortest path), and on a Rhumb Line (a route for which the bearing remains constant).

The button marked 'Reverse' interchanges the starting and finishing points, thus allowing the calculation of the route in the reverse direction.

Notice the considerable differences between these two routes. One thing that the numbers do not indicate is that when travelling on a Great Circle course, the required bearing is constantly changing. Thus the reverse course is a mirror image of the original only for a Rhumb Line course.

At the bottom of the window, in the middle, the log book icon allows saving of the calculation to a plain text log file.