Tuesday, July 13, 2010
From the Trainer:
Here's a good subject for a praxis: AO Maps.
Folks can go to www.mytopo.com and build 1:50,000 and 1:25,000 MGRS (Military Grid Reference System) maps for large AO's.
All they have to do is choose the 36X48 inch size map, orient it the desired direction (tall or landscape), center the area, and they've got an AO map. Subsequent smaller area maps can be generated from the specific AO in question for detailed navigation.
Why 36X48? Because they cover 860.6 square miles or 550,784 acres. If the AO for the group in question is not as large, they should get a 1:25,000 scale which will cover 215.8 square miles or 138,112 acres.
These will come in very, very handy, especially when used in conjunction with a protractor and a lensatic compass. The GPS satellite system is nice, but once is shut down or has a large error programmed into them, it will be irrelevant.
Cost for the larger maps starts at $29.95 and will go up depending on the paper and the detail required, such as aerial photos or hybrid maps, which are great, by the way, but you get what you pay for. In the end, more detail means more accuracy. I used the free enhanced relief on a simple topographical map with MGRS. Some of the Map Source Data is from 2001 (and even later) as you'll see in the example link, so they're pretty up to date.
As is appropriate to Alabama, I used Birmingham. http://www.mytopo.com/review.cfm?mytopoid=499180C8FA
Once the page comes up, click on "View a preview of your printed map". It'll take a couple minutes to load a thumbnail, but click on it and it will be readable quickly.