Navigation/Coordinate systems lesson

Subject
This lesson plan reviews and touches on the coordinates systems that may be used in our area:
 * UTM
 * Geographic Coordinates (Lat/Long)
 * Legal Land Description

Authors
Brett Wuth

Objectives
At the conclusion of this lesson the participants:
 * 1) will be able to ...

Time Plan
Total Time: 120 minutes

Introduce topic title

Introduce Instructor

Present Objectives

Distribute maps, pencils, erasers


 * safe pencils to use on maps
 * safe eraser to use on maps

coordinates systems

A coordinate system is a way of specifying a location on map

3 systems you're likely to use in SAR.


 * UTM - Universal Transverse Mercator
 * Geographic Coordinate System - Latitude/Longitute
 * Legal Land Description - Section, Township. Roads and Approaches

UTM
 * SAR uses mostly
 * taught in SAR fundamentals


 * 3 parts: ZEN
 * Zone
 * Easting
 * Northing

Zones


 * Each zone is a grid system that stretches from near the antarctic to the far north
 * different strips necessary because laying a square grid on a round world
 * Each zone is 6 degrees wide
 * Pincher Creek is right at the boundary between zone 11U (on west) and zone 12U (on east)
 * Each map shows it's zone

Northing
 * how far north of the equator (in meters)
 * written on left and right edge of map
 * horizontal blue lines have same northing
 * every 1000m
 * only 2 of the digits are shown for most blue lines

Easting
 * relative to the center of the Zone
 * center of Zone is 500,000m
 * bigger number the further east you go
 * smaller number as you fo west
 * written on the bottom and top edge of the map
 * vertical blue lines have same easting
 * sometimes starts over from 99 to 00 (with carry)

Stating a UTM
 * order: Z - E - N
 * e.g. 12U 710000mE 5477000mN
 * find this location: middle of Beauvais Lake

Being more precise
 * estimate inside blue square
 * using roamer

Short form UTM
 * used mainly over radio
 * 6 digits (3 easting, 3 northing, no zone)
 * assumes they know which map you're using
 * accurate to 100m

Geographic Coordinate System
 * Latitude and Longitude
 * used by aircraft
 * Better when dealing with 100's of kilometers
 * used by untrained people (all they've heard of)

Degrees


 * A circle has 360 degrees.
 * World is a sphere. Equator is a circle.
 * measure longitude West 180 degrees along the equator from the prime meridian (Greenwich England)
 * measure East 180 degrees
 * meet at about the International Date Line in the Pacific


 * Measure north or south along the longitude to get the latitude
 * 90 degrees Latitude North to the north pole
 * 90 degrees South to the south pole

Minutes


 * Degrees are too big
 * Every degree of latitude is 60 nautical miles
 * = 69 miles
 * = 111 km


 * On the equator a degree of longitude is also 60 nautical miles
 * gets smaller the closer to the poles you get


 * Degrees are divided into 60 minutes
 * written as '
 * 1' of latitude is 1 nautical mile
 * = 1.15 miles
 * = 1.9 km


 * 1' of longitude varies depending on how close to the poles

Seconds

Getting even more accurate.
 * 60 seconds in a minute
 * written as "
 * 1" of latitude is 101 feet
 * = 31m

Full Lat/Long


 * example: 49deg 23' 24" N, 114deg 20' 25" W

Reading on a map


 * latitude goes from bottom to top along edges of map
 * each minute is marked by a black or white bar
 * seconds have to be estimated


 * longitude goes from right to left along top and bottom edge of map
 * size of minute is different


 * no lines join opposite sides of map
 * gray lines (township and section) are sometimes close
 * roll edge of map to create temporary straight line
 * read degrees and minutes, estimate seconds

Exercise

find lat/long of several features

Convert by GPS


 * create waypoint in one coordinate sytem
 * display in another


 * need to match Map Datum used on map

Question bank
See

License
Copyright © 2013, Brett Wuth.

This work is licensed under a Creative Commons Attribution-NonCommercial 2.5 Canada License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/2.5/ca/ or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.

Reference Material
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