compass test vs GPS

12:59 a.m. on December 3, 2009 (EST)
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Hi to all you compass oficianados. This is a test but you have to be able to use Google Earth. If you don't have google earth download it, then go the "fly to" box in the upper left corner and type or copy and paste and then click on the magnifying glass. It will zoom into that spot.

44 11 09.51 n 121 38 27.98 w

I was sitting at that spot the other night at sunset. I had about one gallon of gas in my truck and it was dropping below freezing. You can zoom in and out using the rolly thingy on your mouse or you can go to vertical bar on the upper right that has a + on the top and a - on the bottom. Zoom out about 25 miles high viewing altitude - read off a digital display on the lower right corner of the screen. At that height you should be able to see the Three Sisters volcanoes and the town of Sisters on the screen at the same time. To make it really easy on you lets say you happen to have a clear view of the mountains (you don't actually its in forest).

Now zoom in to about 12,000' to 14,000' so you have a clear picture of the roads in the area, theyre all dirt and they aren't exactly as pictured because the data for the map is old. Now back out to about 18,000' and all you know is that you are someplace on the screen because you've been 4wheeling for a while and all know is that you are on one of those roads in that area, you don't know that you are at that spot because you don't have a GPS. But you have this awesome map and a normal backpacking compass. You need to locate a road that goes back to Sisters and you don't have the gas to make many errors. You take a bearing on those peaks or you measure the direction the road goes where you are but there are too many trees to actually see where the roads go, all you have is a compass and this map that you can zoom in and out.

oh and the roads toward the mountains are getting higher and have more snow, enough that you are concerned about driving in it.

Tell me how you will determine where you are? Without traveling in a straight line north or east, (which would take the truck cross country) how will you get back to Sisters with your remaining gas?

I simply turned on the light, zommed in on my GPS display and drove. I could see that I was not going in the same direction that I came in on because my GPS showed that my track was getting longer so I turned around. As I drove I could see that my "location" was moving along the prerecorded track that I made coming in. Every couple miles I looked and sure enough the center of my screen showed the prerecorded entry path. Soon I was back home in Sisters and entered the coordinates into google earth to see where I had been - you see - I didn't even have a map in the truck, all I new was that I was in the mountains, it was getting dark and cold and that I was following the exact track that I followed to get in.

Thats why I carry GPS and neither a compass or a map.

Or assume your truck is parked exactly at that point and youve been hiking for a while along the twisted roads and then gone cross country for a ways so you don't have a simple compass bearing and you're maybe a mile up hill from the truck - find it before dark.

Thanks for your indulgence. Jim S

7:59 a.m. on December 3, 2009 (EST)
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OK, I'll bite: what would you have done if your GPS unit picked that day to die on you? ?

1:40 p.m. on December 3, 2009 (EST)
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Jimmy,

Your "challenge" would make more sense if you had stipulated that you have been dropped blindfolded into the location. But you said you drove there. First rule of navigation, as you well know, is to pay attention to where you are going, looking around, including behind you.

Tom, first part of the response is that "I remembered to bring the cigar-lighter plug for the GPSR, so I don't have to worry about battery power". But my personal experience was the day (in Antarctica) when my Garmin 60CSx somehow lost its memory (the software version for both sections was ver 0.0, it said). So it was unable to even know where to begin to look for the SVs, or what the PRNs were to do an open search. (Garmin has never been able to figure out why the memory lost both sections of the software.) But I had been following where we were on the map by landmarks, with some help from the compass.

7:53 p.m. on December 3, 2009 (EST)
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BS

So are you saying that your passive compass worked down there? I've had a passive compass reverse its direction of point.

The fact that I drove there is immaterial, the purpose was to show that merely having a map or a compass can be totally worthless and anyone who thinks they will find their way with them is seriuosly misguided - ha ha

JS

9:31 p.m. on December 3, 2009 (EST)
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that merely having a map or a compass can be totally worthless

Very true.


anyone who thinks they will find their way with them is seriuosly misguided

Ouff! I don't know where to start! I have a feeling this thread will be interesting...

10:55 p.m. on December 3, 2009 (EST)
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Franc

Or will it be boring? I could give many better examples but it wouldn't change anybodies mind. I figured the ten essentials refered to survival, as in to help someone lost, but peops think they won't get lost if they have a compass, and others think GPS are unreliable, never mind that they are used to deliver smart munitions.

I'm already too bored to go on.

Jim S

6:15 a.m. on December 4, 2009 (EST)
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I think it's fine to flout conventional wisdom -- it's been an article of faith on outdoor boards since I've been reading them that GPS cannot be relied upon to save your bacon in a survival situation. Frankly it can save your bacon, if you know how to use it (till you lose battery power).

Frankly I find the complexity of my Garmin GPS unit maddening and the software support insufferable. Just figuring out how your GPS unit works is easily as difficult as learning to read a map with a compass. Loading base maps and tracks is another can o' worms (mine allows only 500 track points -- about three miles of hiking -- so I have to cut and paste tracks to get useful routes. Aggravating).

Perhaps a useful guideline for GPS is to never stray further than your unit's battery power will last. The likelihood of it just plain dying on you for no reason is very small compared to the chance of its batteries running dry. I generally never walk more than a couple hours without knowing exactly which trail I'm on. I missed a turn last month that took me four miles off-course; my GPS unit revealed the error, but the only way I knew for sure I was going the wrong way (in deep woods with overcast) was to compare my GPS track to the shape of the the trail on my map.

I still find there's no substitute for a good ol' paper map produced by a professional mapmaker.

2:01 p.m. on December 4, 2009 (EST)
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As a colleague of mine once said in an invited talk he gave at a meeting of our professional society (American Astronomical Society - my professional training is as an astrophysicist) -

Don't confuse the tools of the trade with the trade itself. Having a telescope does not make you an astronomer. Having a computer does not make you a computer scientist. Having a hammer and saw does not make you a carpenter.

In the present context, I would add having a GPSR, or a map, or a compass, or an altimeter, or a sextant or a whole truckload of electronic and non-electronic navigation-related things does not make you a navigator or pathfinder.

The bottom line is that if you do not understand your tools, how to use them, and their limitations, you have nothing but toys that are just useless dead weight.

I would contend that the majority of people in the woods and hills or in the city have few or no skills in using map, compass, or GPSR. Google Earth is just a bunch of pretty pictures you can zoom in and out and pan for 99% or more of the people who ever look at it.

But for that fraction of a percent who have made the effort to use the tools, map, compass, GPSR, altimeter, sextant, etc are extremely useful.

Having spent the last decade of my life as a "salary-man" working as a systems designer and analyst for the Global Positioning System, I am always happy to see people using my product. At the same time, I am more than a little dismayed at how many people treat their GPS receiver as a magic black box that will save their butts no matter how little they understand it (GPSR is the proper acronym - GPS means the entire Navstar Global Positioning System: space vehicles, ground control system, and user systems, one of which is a GPSR). Sorry, folks, it ain't magic. That little chip in your cell phone or that pocket-sized piece of electronic gadgetry has a lot of limitations that can get you in a heap of trouble really fast if you do not understand those limitations, just as a map or compass can.

Jim, don't forget that you are a highly trained and experienced engineer. You have been on both the design and application end of things, unlike the majority of people out there. That makes a huge difference.

4:15 p.m. on December 4, 2009 (EST)
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I just don't trust any battery powered device and I wouldn't never carry one o'them thar battery powered flashlight thingamajigies neither.

Jim

http://farm3.static.flickr.com/2683/4158838642_49fc571cc4.jpg

3:56 p.m. on December 5, 2009 (EST)
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I was wondering where my carbide lamp got to.

Carbide has become virtually impossible to obtain, except maybe in Or-e-gone

July 30, 2014
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