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.
Figure 1. Using a magnetic compass.
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.
Figure 2. GPS Compass display. The bearing to the destination is 298°. The hikers heading is about 115°.
·
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.
As shown (figure 2 above), the GPS
provides direction (298°) and distance (10.2 miles) to the waypoint. The direction is the “Bearing” to the
waypoint. The red arrow and digital read
out provide the return direction to the waypoint, in this case is 298°. (The
red arrow points the hiker to the waypoint.) As the hiker moves down the trail, expect the
receiver to provide continuous updates to the selected destination. Movement on the will may cause the red arrow
to move and the digital information to change too.
Note that the return direction (Bearing)
to the original waypoint may very likely be different than the heading as the
hiker moves down the trail. Heading is
the hiker’s direction of travel, his path through the backcountry. In the example (figure 2 above) the heading is
115°; the direction of movement. Later, as
the hiker moves directly to the waypoint, both the bearing and heading may be
the same.
·
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.
- In this view, the wide blue line is the GPS track; the
hiker’s historical path through the woods.
The exaggerated black triangle points in the direction of travel. (The
other red and brown lines are logging roads.)
To obtain this type of presentation the GPS has been left on capturing
satellite data during the entire hike.
Using the black triangle, the hiker can follow his movement down the
trail to the waypoint destination such as “CAMP” at the bottom right of the
screen.
·
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.
