Originally posted by akash386
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As opposed to more usual projections an important consequence of conformality is that relative angles at each point of the map are correct, and the local scale (although varying throughout the map) in every direction around any one point is constant. This means that in smaller areas of the map, like the continental US or Western Europe the compass headings and distances are true. This is important and helpful for both pilots and local or adjacent Area Traffic Controls. For longer distances and transcontinental flights various forms of GPS navigation and/or gyrocompasses are used to plot out a Great Circle Map route because polar areas cannot be represented in any Mercator projection.
On an ordinary map Greenland seems bigger than Africa although Greenland is only one fourteenth of its size. Similarly Finland seems as big as India when in reality India is ten times the size of Finland.
Most people use Google Maps. It uses a Web-Mercator projection with WGS84 data to pinpoint places. This is useful only in local close-ups. In world wide view the map slowly turns in to a globe. It cannot be used for accurate navigation.
The Conformal Transverse projection and variations of it were developed by the US Army Corps of Engineers and it is or has been used by NOOA and NATO systems and the current US Military Grid Reference System is based on it.
The Universal Transverse Mercator coordinate system
Map projection
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