IMO, there are three basic ways to use a GPS on a bushwack:
1a) Follow someone else's track. While the travel may be rougher, navigation-wise it is little different from following a trail.
1b) Make your own track at home and follow it. (Ie the same as 1a except for the source of the track.) As peakbagger noted, there are things on the ground that may not show (of may not be noticed) on maps...
2) Use the GPS to provide headings to some intermediate and/or final pre-planned waypoints and travel between the waypoints using the path of least resistance. This is essentially the same as traditional non-GPS bushwacking except that one can include electronic reference points and can be combined with non-GPS methods.
3) Turn the GPS on at the trailhead, reset the trip computer, throw it into your pack and leave it there until you get back to the car where you check the trip computer. You can think of the GPS as a super pedometer... However, it is a form of safety gear and you may be bolder because you know you have a navigational backup it your pack. (Also known as carrying your security in your rucksack...
) After you get home it can also be nice to check your tracklog so you can see where you actually went.
I personally generally use 3), rarely look at the GPS while hiking, and finally check the trip computer to see how far and fast I/we went. If the route was unusually interesting I may check the tracklog, but often don't bother (particularly if the hike was on mapped trails).
And of course there is the option to not bring the GPS at all. These days when on recreational bushwhack trips I may bring a GPS as Neil and Doug do in mode 3), but if I don't bother to have a GPS with me it is not a big deal at all. While it is certainly a great safety device and operational tool, I grew up navigating without needing one and that remains true today. With a bit of map study and understanding of how to truly navigate, it is not terribly difficult to know your position to the degree necessary at all times from compass and map with terrain observation, using dead reckoning in the more difficult areas, and to then draw your own real-time or post-trip track log. It is always a good idea to do both pre-trip and post-trip navigation analysis, as both will improve your navigation skills immensely.
I have used 2), for instance when solo hiking Isolation from Rte 16 in winter. I was following a traditional largely off-trail M&C route and placed waypoints at the turns of the bushwack portion. (I also carried a written list of the leg distances and headings.) I didn't actually try to hit the waypoints exactly--just get near enough to them. I did place a waypoint at a good stream crossing to make sure that I could find it on the way back if need be. My GPS was off most of the time and I only turned it on a few times for a few minutes to get a heading to the next waypoint which I then dialed into my compass. If necessary, I could have done the route without the GPS, but I was happy to have the backup.
When I pre-trip-plan a bushwhack route of a fair distance, there are almost always reasonably spaced visually identifiable natural terrain features that will mark intermediate points on the way to the destination. They may require a slightly zig-zag course, but to me that is the point of recreational off-trail hiking. Find one after the other to verify your exact intermediate location, then follow a measured compass headings and terrain to the next until the final destination is reached. My trip memories are often more filled with what I saw and experienced (and learned) all along the way than when I got to to the end point. If changes from the pre-plan, such as recent beaver meadow floods or blow downs or any other number of reasons determine otherwise, just alter course and deal with it.
On the other hand I can't do my job as a SAR Crew Boss without a GPS in my hand and recording tracks. When the operations chief gives me responsibility to lead a search crew team in a particular assigned sector block of land, there is no substitute for a GPS in mode 2) to ensure I arrive at my assigned block and perform a thorough search of the entire precisely defined area. If my assignment begins some distance away from the staging area and no transport is available, I plot the best course on the GPS (always with a real map reference) for my team to walk to the closest corner of my block to begin the search sweeps. Reference to the assignment on the SAR topo map and terrain observation confirms what the GPS is telling me is correct throughout the process. At the end of the assignment the incident command planners will download my GPS track to verify the area coverage. Since this is such an important function to efficient SAR, I often carry a second backup tracking GPS to be sure data is recorded. The GPS is fast and efficient as the best tool to use for such a time-sensitive job, and with all the other backups there are no real consequences to myself by primarily depending on the electronics if the GPS unit fails. I'm not really out there to enjoy the sightseeing or to find a destination as the only goal.
I guess you could say that I use 1a/b) during canoe races. For most races I know the route well enough so that I have my own finely detailed route memorized, to avoid subsurface rocks and stumps, for example. In those cases I use the GPS for speed maintenance only, to ensure I and my crew are paddling at a target speed (or higher). There is an unofficial night time non-race that I have been paddling for the past several years. Essentially the Adirondack 90-miler route start to end, done unsupported and the whole route all in a single day. Beginning at midnight the first several hours are paddled in complete darkness, more often than not in thick fog in the wee hours of morning. So in the fog my well trodden GPS route comes in handy there, following an exact known route between invisible waterway obstacles and turn points.
When I first paddled the Yukon River races (440 mile and 1000 mile), as a planning start I used charts from the old paddle wheeler days of the early 1900's to get the basic route in the complex river channels and fast currents. GPS mode 1a). But in reality I knew I could take several obvious shortcuts around turns and between islands in a canoe, so I modified the paddle wheel route somewhat to significantly shorten the distance. Now after 4 races on the river with making experienced improvements to the route each time, I'm happy with the route i have modified, many places trading off shortening the route in sometimes slow current versus staying in fast current over longer distances, to be successful for a 5th return the Yukon. Coordinate registration from Google Earth tends to be excellent with reality, but the Yukon changes from year to year, with shoals and islands and currents often significantly different from the most recent available maps. 793 precisely targeted waypoints make up my Yukon 1000 mile race route in GPS mode 1b).
So while I generally prefer to do my own navigation or follow trails and use 3), 2) can be useful and I view it as a blend of traditional non-GPS navigation and GPS navigation. Or in 2) one can use non-GPS methods while occasionally checking the GPS to verify that you are indeed on the intended route. In all cases, it is a good idea to research the region, route, and escape routes before going out. One can never tell what one may find...
Good advice that I can't argue with at all.
Some accident reports have described situations were a hiker gets confused (lost if you prefer...) and "bends" the terrain to match where he thinks he is. A few seconds with a GPS can cure or prevent such confusion...
I read the weekly SAR reports from the NYSDEC. There are usually several incidents each week, most of them minor. The vast majority are resolved in a few short hours using a couple of rangers only, without calling out other SAR resources. I am convinced that a high percentage of those cases could have been self-rescued if the people would only have done some combination of:
1) Study the route on a map prior to making the trip.
2) Bring a map and compass and understand how to use them.
3) If confused ("lost"), don't panic and immediately resort to using the cell phone. Use the old (pre-electronic age) advise - relax, sit down, review what you did to get there, figure out where you are, and find your own way out to a known location.
4) GPS? Consider it as a tool to get a job done. Understand why you went into the woods in the first place, be it to do a job or rather to enjoy the journey, or just to blindly reach the destination. Use when necessary, but don't rely on it as a your only primary aid.
