Map, Compass & GPS

Map, Compass & GPS
Wild flowers along Fall Creek on the way to the Green Lakes - Oregon

Sunday, November 16, 2014

Land Navigation Errors

Land Navigation is a very perishable skill.  It is a skill that takes practice.  As a SAR team member I find that all to often people who get lost in the back country don't have that skill or the equipment.

In 2012 I came across a blog dedicated to land navigation.  Lyle Brotherton had a super post on the 12 most common errors navigators make. I will highlight just a few his points.

  • Compass deviation - Keep ferrous objects away from the compass body.  Items such as rifle barrels, watches, ice axes and some electronics will impact compass accuracy.
  • Declination - Keep your navigation simple and buy a declination adjustable compass like the Silva Ranger; that's a great compass for the price.  Verify your declination and visit for current data.  Many maps are dated and present declination information that is out of date. 
  • Orient the map - Orient your topographic map at the trailhead and at trail junctions.  The map and its features (terrain, streams, man made objects) should correlate with the ground that is laid out before you.  If terrain and map do not agree pause until they do.  For more information on orienting a map go here.

  • Compass bearings - Keep your compass close at hand.  When shooting a bearing turn your body to the bearing don't just turn the compass base plate.  For more information about shooting a bearing go here.

  • Terrain Clues -  Key terrain features such as mountain peaks, trails, waterways and
    elevation should be compared regularly.  This begins at home before striking out.  Study the map to develop a mental image of the backcountry route; his pays off once in the field.
  •  GPS receivers - A few recommendations:
    1. Keep fresh batteries in your receiver
    2. Delete old waypoints that haven't been used recently
    3. Give important waypoints a name such as camp or truck
    4. Calibrate the electronic compass after changing batteries 
    5. Delete the old track log (the bread crumb trail) via the track manager
To read Lyle Brotherton's complete post  go here.

No comments:

Post a Comment