– Ortho-Cities flight2000it 16 years ago Ortho-Cities orthodromic calculator. Useful for inertial navigation systems, calculating distances on the Earth. Offers easy input of coordinates from the list of selected airports. By Bohumil Stadnik. 250 Kb X-Plane 9.70 – Scenery 61S Cottage Grove StateX-Plane 9.70 – Scenery S05 Bandon StateX-Plane 9.70 – Scenery S51 Andy McBeth