GPS: Primary and Backup Navigation
I’m a pilot and one of the things that comes up over and over again in flight school is always having multiple methods of navigation. You never want to rely on only one means of navigation. Sometimes pilots navigate via “dead reckoning” where you follow the compass on a particular heading for a certain amount of time. Other types of navigation include “pilotage” where you navigate by looking at sectional charts and matching what you see from the air with what you see on the chart. Pilots also can use GPS to navigate, as well as other means of radio navigation (like following VORs) and inertial navigation systems. So what does this have to do with those of us who use GPS in our cars or during outdoor recreational activities?
Even in those activities it is always a good idea to have a backup to your GPS based navigation or only use GPS as your backup means. Most everyone who has used a GPS for road navigation knows that gps maps can be outdated and provide incorrect information. I’ve read numerous “off-beat” reports citing someone who drove into a stream or onto a closed road because they were too closely following the instructions of their GPS and not paying attention to their surroundings.
The lesson learned there is you need to exercise some common sense and pay attention to what is going on around you. Just because your GPS says to turn right doesn’t mean it knows about the road closure. Take advantage of the re-routing feature nearly every GPS has and let it route you around the closed road.
The same goes for outdoor use of GPS. Many “purist” hikers for example scoff at those who carry a GPS device with them. They suggest not to rely on anything that uses batteries as batteries can fail. I like to point out that I agree…. they should not “rely” on GPS, but rather use it as a tool available to them. A compass and map can be your primary means of navigation, but there shouldn’t be anything fundamentally wrong with carrying a GPS as a backup. Just like a first aid kit, hopefully you won’t need it, but carry it just incase.
GPS devices are wonderful, but understand their limitations. Eventually the batteries will run out an the maps are sometimes wrong. Be smart and always have a backup means of navigation.