{"id":14206,"date":"2025-06-03T16:09:53","date_gmt":"2025-06-03T10:39:53","guid":{"rendered":"https:\/\/ibexaviation.com\/pilot-training\/?p=14206"},"modified":"2026-07-26T10:09:40","modified_gmt":"2026-07-26T04:39:40","slug":"great-circle-and-rhumb-line-tracks","status":"publish","type":"post","link":"https:\/\/ibexaviation.com\/pilot-training\/great-circle-and-rhumb-line-tracks\/","title":{"rendered":"Great Circle and Rhumb Line"},"content":{"rendered":"<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-1.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<h2>Great Circle and Rhumb Lines<\/h2>\n<p>A Great Circle is the shortest distance between two points on the Earth&#8217;s surface. Its direction (bearing) changes continuously during the flight, making it the most fuel-efficient route for long-distance travel. A Rhumb Line (Loxodrome) is a path that crosses all meridians at the same angle, so the aircraft maintains a constant heading. It is longer than a Great Circle route but is easier to navigate, especially for shorter distances.<\/p>\n<h3>Vertex of a Great Circle<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-2.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Great circle vertices are the northernmost and southernmost points of a great circle.<\/li>\n<li>The <strong>Northern Vertex<\/strong> is the point on the great circle closest to the North Pole.<\/li>\n<li>The <strong>Southern Vertex<\/strong> is the point on the great circle closest to the South Pole.<\/li>\n<\/ul>\n<h3>Properties of Great Circle Vertices<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-3.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The northern and southern vertices are antipodal points.<\/li>\n<li>Antipodal means diametrically opposite points.<\/li>\n<li>The shortest distance between the vertices is <strong>10,800 NM<\/strong>.<\/li>\n<li>Flight along a great circle results in a continuous change in direction.<\/li>\n<li>At either vertex, the great circle direction is due East or West.<\/li>\n<\/ul>\n<h3>Latitudes and Longitudes of a Great Circle<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-4.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The numerical value of the latitudes of both vertices is the same but in opposite hemispheres.<\/li>\n<li>The longitudes of the vertices lie on a meridian and its anti-meridian.<\/li>\n<li>An anti-meridian is the meridian located 180&deg; from a given meridian.<\/li>\n<\/ul>\n<h3>Equator Crossing of Great Circles<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-5.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Great circles intersect the Equator at two points.<\/li>\n<li>Each intersection occurs at a longitude 90&deg; from the vertex.<\/li>\n<li>The angle between the Equator and the great circle equals the latitude of the vertex.<\/li>\n<li>This relationship allows calculation of the great circle track at the Equator crossing.<\/li>\n<\/ul>\n<h3>Equator Crossing on an Easterly Track<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-6.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>North-to-South Equator crossing = <strong>90&deg; + Vertex Latitude<\/strong>.<\/li>\n<li>South-to-North Equator crossing = <strong>90&deg; \u2212 Vertex Latitude<\/strong>.<\/li>\n<\/ul>\n<h3>Equator Crossing on a Westerly Track<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-7.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>North-to-South Equator crossing = <strong>270&deg; \u2212 Vertex Latitude<\/strong>.<\/li>\n<li>South-to-North Equator crossing = <strong>270&deg; + Vertex Latitude<\/strong>.<\/li>\n<\/ul>\n<h3>Properties of Rhumb Line<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-8.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Rhumb lines are uniformly curved lines joining two points on the Earth&#8217;s surface.<\/li>\n<li>Meridians converge toward the poles.<\/li>\n<li>A rhumb line intersects every meridian at the same angle.<\/li>\n<li>Rhumb lines maintain a constant track direction with respect to True North.<\/li>\n<li>The track angle between True North and a rhumb line remains constant.<\/li>\n<li>Only one rhumb line can be drawn between any two points.<\/li>\n<li>Infinite rhumb lines can be drawn between diametrically opposite points.<\/li>\n<\/ul>\n<h3>Equator is a Special Line<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-9.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The Equator is both a rhumb line and a great circle.<\/li>\n<li>As a great circle, it represents the shortest distance.<\/li>\n<li>As a rhumb line, it has a constant direction.<\/li>\n<li>The Equator is a great circle with vertices at 0&deg; latitude.<\/li>\n<li>It has infinite vertices pointing due East or West.<\/li>\n<li>All points on the Equator have a constant direction of <strong>090&deg;<\/strong> or <strong>270&deg;<\/strong>.<\/li>\n<\/ul>\n<h3>Meridians are Special Lines<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-10.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Meridians are both rhumb lines and great circles.<\/li>\n<li>As great circles, they represent the shortest distance.<\/li>\n<li>As rhumb lines, they maintain a constant direction.<\/li>\n<li>Meridians have vertices at <strong>90&deg; North<\/strong> and <strong>90&deg; South<\/strong>.<\/li>\n<li>Meridians intersect all latitudes in northerly and southerly directions.<\/li>\n<li>All points on a meridian have a constant direction of <strong>000&deg;<\/strong> or <strong>180&deg;<\/strong>.<\/li>\n<\/ul>\n<h3>Rhumb Line and Great Circle Directions<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-11.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Rhumb lines maintain a constant track direction.<\/li>\n<li>Great circles do not maintain a constant track direction.<\/li>\n<\/ul>\n<h3>Rhumb Line and Great Circle Distances<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-12.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Great circle routes provide the shortest distance between two points.<\/li>\n<li>Rhumb line distances are always greater than or equal to great circle distances.<\/li>\n<\/ul>\n<h3>Appearance of Rhumb Lines and Great Circles<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-13.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<h4>Great Circle<\/h4>\n<ul>\n<li>Great circle tracks are convex toward the nearer pole.<\/li>\n<li>Great circle tracks are concave toward the Equator.<\/li>\n<\/ul>\n<h4>Rhumb Line<\/h4>\n<ul>\n<li>Rhumb lines are convex toward the Equator.<\/li>\n<li>Rhumb lines are concave toward the nearer pole.<\/li>\n<\/ul>\n<h3>Great Circle vs Rhumb Line<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-14.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>A rhumb line is a regularly curved line with constant direction.<\/li>\n<li>A great circle track changes direction continuously.<\/li>\n<li>Up to the midpoint, a great circle moves toward the nearer pole.<\/li>\n<li>At the midpoint, its direction matches the rhumb line track.<\/li>\n<li>After the midpoint, it gradually moves toward the Equator.<\/li>\n<\/ul>\n<h3>Value of Great Circle Track in the Northern Hemisphere<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-15.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The numerical value of a great circle track depends on the hemisphere and direction of flight.<\/li>\n<li>For easterly tracks, the track value increases while moving toward the North Pole (clockwise).<\/li>\n<li>For westerly tracks, the track value decreases while moving toward the North Pole (anti-clockwise).<\/li>\n<\/ul>\n<h3>Value of Great Circle Track in the Southern Hemisphere<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/general-navigation\/g3-great-circles-and-rhumb-lines-16.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The numerical value of a great circle track depends on the hemisphere and direction of flight.<\/li>\n<li>For easterly tracks, the track value decreases while moving toward the South Pole (anti-clockwise).<\/li>\n<li>For westerly tracks, the track value increases while moving toward the South Pole (clockwise).<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Great Circle and Rhumb Lines A Great Circle is the shortest distance between two points on the Earth&#8217;s surface. Its direction (bearing) changes continuously during the flight, making it the most fuel-efficient route for long-distance travel. A Rhumb Line (Loxodrome) is a path that crosses all meridians at the same angle, so the aircraft maintains a constant heading. It is longer than a Great Circle route but is easier to navigate, especially for shorter distances. Vertex of a Great Circle Great circle vertices are the northernmost and southernmost points of&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"disable_featured_image":false,"footnotes":""},"categories":[324],"tags":[],"class_list":["post-14206","post","type-post","status-publish","format-standard","hentry","category-cpl-atpl-general-navigation"],"_links":{"self":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14206","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/comments?post=14206"}],"version-history":[{"count":1,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14206\/revisions"}],"predecessor-version":[{"id":16620,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14206\/revisions\/16620"}],"wp:attachment":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/media?parent=14206"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/categories?post=14206"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/tags?post=14206"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}