The hike into the backcountry has come to an end. Now it’s time to return to the trailhead. By selecting “Find” or “Where Is” the GPS receiver
provides direction to the trailhead.
Before returning, the hiker should review several GPS navigation
considerations:
·
The Electronic compass: It must be calibrated after each battery
change. If the hiker doesn’t remember
doing this, calibrate the receiver. Bearing
information will be more accurate by several degrees.
·
Distance information: This data (e.g., 10.2 miles) is line of sight
or more commonly, “as a crow flies.” The GPS receiver doesn’t take into account
topography and detours that may be needed.
Thus, a distance of 10.2 miles may really be 11.2miles or more at the
end of the hike.
·
Bearing: Make sure that bearing information
is presented in degrees and not “cardinal letters” such as NNE (North North
East). The hiker’s compass provides
direction information in degrees. When
aligned this keeps navigation simple; both compass and GPS complement each
other. Make this change by adjusting the
compass setup.
·
GPS Map Page: Select the map page. Use this page to corroborate the electronic
compass information.
Figure 3. The blue squiggly line is the recorded track; it
is where I have been. The black triangle
indicates my position on the map page and the direction travel.
·
Bushwhack:
Occasionally the hiker may elect to bushwhack from a current position to
a new destination. The hiker should
consult the map to assess the overall big picture to determine if the route is
safe, find and identify natural obstacles and evaluate terrain.
·
Map and Compass: Don’t leave these important tools stuffed away
in the pack. Practice with them during
the hike. For example, use the map and
compass to orient the map to get the general lay of the land. Use the compass to further evaluate the
bearing to a destination. For example, the
GPS’ determines that the bearing to the trailhead is 298°. Use the compass to sight a bearing of 298°
and follow the compass rather than the GPS’ electronic compass.
Navigation is not hard but it takes
practice and repetition. Don’t assume
you will have the same visual landmarks on the return trip. A change in weather (fog and snow) can
increase the complexity of your navigation.
Practice and experience significantly helps develop confidence in the hiker’s
skill level and equipment.
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