Comment by holgerschurig
8 hours ago
> Mercator useful for sailing+
It is also used by the military (or at least NATO). They use https://en.wikipedia.org/wiki/Universal_Transverse_Mercator_...
While most of that system is a way to tag coordinates that are "simpler" than just latitude and longitude to a position, it's underlying system is also the Mercator projection. And some properties of Mercator, e.g. that it is angle-correct. So you can use UTM e.g. in Elint for direction finding.
It's not distance or area correct, but for normal infantry this is meaningless, since this only shows on large scales, but not the slow scales of infantry.
The transverse Mercator projection is completely different than what people are complaining about. The UTM system is roughly what you get if you only take a narrow band of the ordinary Mercator projection near the equator, but turn the globe 90°, and use the projection for a narrow strip of a specific longitude, with a different projection for each strip, overlapping at the seams.
It was adopted by the US military between WWI and WWII, and similar projections were adopted by other militaries around the same time, because earlier (non-conformal) map projections led to dramatic errors when they were used for artillery targeting.
Maybe to be more precise, conformal projections like the transverse Mercator projection and the conformal conic projection were adopted by militaries after WWI, and the UTM system per se was created during WWII.