[crashdive123]

Alpine Zone - I'm looking forward to your tutorial on the use of a compass. Thanks for doing that.

A note on the GPS though - clouds, rain and snow do not attenuate the signal. Trees and other canopy's do though.

[kevin]

Alpine, navigation is one of my favorite topics. look forward to your post. would love to here your recommendations for getting out of an above tree-line featureless whiteout when it's too damn cold and windy! how do you control the map? follow bearings? etc.

[AlpineZone]

Originally Posted by kevin

Alpine, navigation is one of my favorite topics. look forward to your post. would love to here your recommendations for getting out of an above tree-line featureless whiteout when it's too damn cold and windy! how do you control the map? follow bearings? etc.

Kevin, never have I been caught in a whiteout above treeline. This really isn't about navigation at this point as it is survival. Watching radar maps and the pressure domes is very important before heading out especially above tree line in the winter. And plan an escape route ahead of time in case the weather closes in unexpectedly you get down out of the wind/driving snow.

If you are caught in one above treeline, your best bet if your alone is stop where you are if the visibility is gone and setup your Mt tent and wait it out or dig a snow cave or makeshift shelter using your bivy sack/ garbage bag whatever you have. If your with a party rope up together so no one gets lost providing you have visibility to carry on and the party is strong enough. The physically smallest in the front to the strongest in the back is the order you rope up in. If you have an ice ax with you give it to the person in the back if you need to self arrest, preferably everyone should have one. Again, if visibility is zero the party should dig in, stay put, stay close for warmth, light candles, handwarmers, stuff extra clothes in your jacket/pants, sleeping bag, be patient and stay calm.

In a whiteout with zero visibility its virtually impossible to tell the ground from the sky and what direction your heading even if you know the area well without instruments. It can be very unnerving not to mention its an easy way for disaster to happen like walking off a cliff, hyperthermia, frostbite to extremites or worse, dehydration from the massive physical output.

Hope this was useful.

[Bladed]

One thing to consider is that if SHTF with the Government, they will shutoff the civilian GPS signals, so learning to use a compass and map is a pretty important skill.

[crashdive123]

Originally Posted by Bladed

One thing to consider is that if SHTF with the Government, they will shutoff the civilian GPS signals, so learning to use a compass and map is a pretty important skill.

Actually, all they can really do is disable the P code. When that happens your accuracy decreases. Still not too bad - more like Loran-C type accuracy.

[Bladed]

Originally Posted by crashdive123

Actually, all they can really do is disable the P code. When that happens your accuracy decreases. Still not too bad - more like Loran-C type accuracy.

Still a GPS requires power, a compass doesn't so why carry more than you have too?

Was thinking about this some more and I realize that yes they could disable the code, or since they have control of the satellite they can reprogram it to only work with military and government gps systems.(how ever if you get a Russian made GPS they have a complete different set of satellites.)

[Ashlar]

Just a note I haven't seen brought up yet.

The "Order of Working" when converting from magnetic to true or vice versa, is as follows (if memory serves correctly)... I spent some time in our Coast Guard (non-military, search and rescue only), so let's see if I can recall it correctly:

Write this down the page:

T
V
M
D
C

(Remember the old sailor's mnemonic: true virgins make dull company (TVMDC))

T: True (true north on your map)
V: Variance (the local magnetic variance wherever you are in the world)
M: Magnetic (magnetic north)
D: Deviation (for boating use - unless you figure it out for your car!)
C: Compass (compass heading)

The "D" step is used in boating because all the metal and magnetism from some electrical systems affects the compass, so a compass adjuster hangs the boat up off the ground and measures the deviation from magnetic north caused by this... so if you use the TVMDC method, you can take a true north heading from your map and translate it to the heading you should use on your boat compass. If not in a boat, disregard the "D" step and I think it should work just fine.

Example:

You want to head 090 degrees true (east on your map). You don't just use that heading on your compass. If your magnetic variance (the variance in your region from the true north) is +10 degrees, you then walk/drive 100 degrees magnetic (on your compass). If you are in a boat, add or subtract the compass deviation listed on your compass adjuster's certificate.

The reverse also works. To go from a compass heading to a true heading on your map, just work in reverse.

This translation of true north to magnetic north is more important the further you go. If you are hiking one mile to an outlook on a small mountain, I doubt the error from not adjusting for magnetic variance would be minimal. You'll still get where you are going.

Sorry if this is a bit confusing, I think I have some sun stroke from working on my car in the heat too long. Just google "order of working" and "compass" or something and it should be explained nicely.

There's a good chance I screwed something up here due to the amount of heat I had today - so please feel free to tell me if I got it wrong.