UKC

Yes thats right you sad people who have gps and have thrown the compass away! just spoken to someone i know who tracks the global postioning satalites for the uk MOD and he said that they have all been set to be at least 100-200m meters out due to the US (the well oiled machine that got it ass kicked!)

Now which Silva compass should i buy? Hmmmmm ooo that looks good!

In reply to Martin P:

I doubt your information is correct Martin. As far as I know, the US unscrambled public use GPS a year or so ago, so that it should be accurate to 10m or so. Someone who uses GPS may like to correct me if I am wrong.

I was on the bridge of the ferry that goes to the Scillies earlier this year. The captain showed me the two GPS's that the ship uses. One is more or less a bog standard issue one such as you or I might use, while the other is a differential one, that communicates with a fixed position station on the lizard, as well as with the GPS satellites. The lizard station knows its own position, compares this with where GPS says it is, and thus calculates the GPS position error. This it then transmits to the ferry, which can then correct the position ascribed to it by GPS.

Since the US flicked the descrambling switch, this differentila capability has become redundant, the captain said. When I was there, both corrected and uncorrected GPSs were giving positions with 5m of each other.

In reply to mbh: Still not much help if the batteries run out!

In reply to ice: Sure. I'm just commenting on the claimed accuracy of GPS, even when it works. Besides GPS, the captain of the ship I was on had magnetic and gyroscopic compasses, two independent radar sets, and sonar. But most of the time, he said, he just looks out of the window.

In reply to mbh: I use differential gps positioning oil rigs and the like - probably 90% of the time raw gps (ie what you'll get from an Etrex or similar) is within 15m of the differentially corrected position (which is supposed to be within 2m of actual position).

Of course this is with an open sky view & good satellite constellation - if you don't have those then it can be out by a lot more.

Chris

In reply to chris j: Really useful in a cairngorms whiteout ....

In reply to ice: Don't get me wrong, GPS does have a use- but firstly- i'd rather spend 200 quid going to chamonix, and they give people who can't navigate a flse sense of security- met a group on top of the glyders with one- they couldn't figure out how it related to the map- as one folornly said- we left the instuctions in the car- did they have a compass? No. Did they know where they were? On the glyders somewhere near glyder fach or was it fawr... What we could do with is an ultralight cheapish emergency radio beacon, so that lost idiots can be found by mtn rescue.

In reply to ice: Yeah - I'd like a cheap basic GPS which just gives out a grid ref. Well handy if you want to check your position after following a compass bearing in a high wind whiteout.

In reply to Martin P:
The trouble with GPS is that you need good visibility of the sky. If you are in a deep valley, the GPS may not get signals from the satellites, and so you get no fix.

The trouble with a compass is that if you go to the Cuillin, it will not point to magnetic north due to the magnetised rocks.

Both compass and GPS are of limited use if you cannot read a map.

In reply to Martin P:
What you are saying used to be true Martin. Until a couple of years ago the GPS was pretty useless for micro nav. We had one in South Africa for plotting archaeological finds found during field walking a mountainous area covering about 20 square km.and found that it could be out by a couple of hundred metres, particularly when trying to plot altitudes. Unfortunately the maps we had for the area were just as vague....
These days I understand that they can be very accurate and precise, though I am naturally suspicious of them all the same. There is no substitute for map reading and using a compass!

In reply to ice:
The problem you mentioned with people going out on the hills without a compass because they have got a GPS. Is that the fault of the GPS or the people using them? You can't blame the existance of GPS's on poor navigation. It can give some people a false sense of security - but that problem lies entirely with the people.

GPS's are fantastic things that should be used to back up a doubtful navigational decision. Even the most experienced mountaineers can't deny the use of them.

In reply to bob: Regarding the concerns expressed about poor sky visability eg. when in a deep vally. If you are somewhere enclosed it is usually easy to find your position on a map as you have identifiable features around you. Most scenarios where ppl get lost occur on featureless plateau or moorland areas where a GPS should work ok.

In reply to bob: Agreed, ikt's not thefault of the GPS unit- which granted can be very usefull- it's just that they are sold as the ultimate do-all navigation device.

In reply to ice: A cairngorms white out is probably when it would be useful - also when you're most likely to get a good position - up on the plateau, no real landmarks - clear sky view (weather is not important).

Shouldn't need to have it turned on for more than 10 minutes or so to get a position, probably less if you turn it on when you leave the car/camp in the morning to get a position & allow the unit to get the current satellite orbital details - then it should get a position in only a couple of minutes 'cause it knows where in the sky to look for the satellites. So the batteries might just last.

i carry a basic Etrex in winter (only £80 in the USA last spring) - keep it turned off unless I get lost - the idea being if I get lost I can turn it on & get a position on the map & then navigate off using map & compass.

Luckily I haven't had to try this for real yet.

Chris

i guess most everyone has covered what i've thought, but as for someone mentioning an enclosed spot, maybe that needs a bit of clarifications? when i hear enclosed, i'm thinking of the canyonlands of the southwest, where you're hiking through a drainage. basically two walls to your side, and great danger of flash floods. granted you might not see that there, but its hard to find yourself with or without GPS. also, regarding a white out, why even bother moving? i think that's quite dangerous, and its a real easy way to get lost. i don't know what a "cairngorms white out" is, but if i'm stuck in a white out, especially in the winter, i'd prefer to just take out my down sweater and sit it out for a while, even get a brew going. unless you're certain of the terrain, i think its best to just sit it out.

bottom line, its just a tool, its not going to help you get un-lost. your best bet is not get lost in the first place, its not as hard as it seems. if you're not feeling confident, take a course, it may save your life.

In reply to Taki:
Regarding your comments about sitting out white outs... In the Cairngorms sitting out a white out means you run a very real risk of being benighted on a plateau with winds gusting over 100mph and temperatures plummetting (It can get dark at 3.30 pm). If you have a rudimentary shelter or can dig a snow hole I guess it might be an option and I guess it depends on whether you are lost to start with or injured or whatever. Much better to get yourself out of it if you can! Itt is possible to navigate in a white out, as long as you know where you are to start with and navigate away from dangerous obstacles like the edge of corries! Again, nothing like a map and compass....

In reply to Lucy (at home): well, i guess that's quite windy... i've been in about 60 mph, that was quite cold. what i meant by sitting it out is to exercise common sense, to find a sheltered place, make sure you're not totally exposed, and then sit it out... or, alternatively, if its easier to go back, do so, or if you're closer to getting there (again, lets use some common sense, i'm talking a few miles walk, if that) go for it... but regardless, in any winter undertaking, better safe than sorry, be prepared... in the White Mountains of New Hampshire, where i hike around, the winters are cold, and winds up in the 3 digits not uncommon. beginning of the month, it was 100+ all week... people falling into crevasses, or getting in an avalanche is not unusual... i guess from that perspective, its better to stay put (again using some common sense). hope this clarifies some.

yes, i agree. nothing better than a map and compass...

In reply to Lucy (at home): Yup - done that after my mate lost the bearing (next day he found the Shelter Stone instead of the Avimore side ski lifts hehehe). Dug out a snow coffin, fairly safe if cold (ps - never leave it's sanctuary for a pee, two steps and you're out of sight once the wind blows you over). But when the storm keeps up during the morning then it's prob best to get off the plateau, unless you have stove and food for a few days. Rope up and keep the axes ready in case the leader walks over a cornice (prussiks might be useful as well)

In reply to Taki:
The Cairngorms are only just sub arctic, some survival friend said they were like the tundra with big drops at the edge. Staying put is only an option in extremis as there is little shelter from the wind and till you hit the lee of the hill little chance of snowholing. Most days in winter the wind on Cairngorm is over force 6 with 20% force 8/9 with the attendant wind chill. Sensible people do climbs on sheltered slopes and only go on the top for a short distance to descend a safe way when it is like that. New hampshire may have areas like it, I don't know but it is a fine line in survival in winter.

In reply to sutty: is there a website that shows what its like? like to check it out someday...

thanks

In reply to Taki:
This site has some nice pictures of what they look like on a good day: http://www.freefoto.com/pictures/scotland/cairngorms/index.asp

There is a weather station that has a website and it's own wecam but it seems to be broken or at least I can't find it any more....

In reply to Lucy (at home): thanks for the info... i've looked around, and found this:

http://www.users.zetnet.co.uk/gshaw/cairngorm_frame.htm

also, if you're interested, check out:

http://www.mountwashington.org/cam/northeast/index.html

for the mountanin that i usually trek around. there's a weather observatory up on top.

In reply to Martin P:

GPS's are crap, use a compass you lazy git!

In reply to Martin P: S'cuse my french but what a load of bollocks. I use a DGPS at work which has sub-metre accuracy and over the past couple of months have tested it against my Magellan just to check SA hasn't been turned back on. And guess what, that's right no difference.

In reply to jude: Luddite.

In reply to jimbo2: I agree. Managed sub metre accuracy in Canada last year. Compass or GPS however, it depends on your level of confidence using them whether they will get you out of danger or not. GPS has the edge in featureless terrain for sure and a 12 cha receiver works practically everywhere, even indoors. I upgraded from a 6 to a 12 and it's worth the extra 30 quid.

Ideally, you should have both on you - I expect most GPS users carry spare batteries and a Silva too ? GPS is bloody good in the dark too.

In reply to Taki: Disagree with a couple of your comments:

"bottom line, its just a tool, its not going to help you get un-lost." Actually I disagree. Assuming that the GPS can get a fix, it *does* get you un-lost because it tells you where you are. Isn't that the definition of being lost: "I don't know where I am"?

What it won't necessarily do is get you *safe*, because if you don't know how to use the information it gives you, you're still stuck, you just know where you are stuck. This is where the map and compass come in. (You can't reliably use a GPS to follow a bearing on foot. The eTrex Summit doesn't switch from compass to GPS for direction of travel until 10kph, which is difficult to sustain across rough ground in good conditions, let alone bad weather & poor visibility.)

"i'm thinking of the canyonlands of the southwest, where you're hiking through a drainage. basically two walls to your side, and great danger of flash floods. granted you might not see that there, but its hard to find yourself with or without GPS." How much of a problem is it, to locate yourself in such a landscape? I'm thinking that if you're in a canyon then the only other piece of information which could be useful is how far along the canyon you are. If the risk is flash floods, then my main concern would be how close I am to a place where I can climb out or away from it! I'll admit it would be different if you were in a "twisty little maze" of canyons and you needed to know which one you were in. Sounds like interesting country, anyway!

In reply to Martin P:

That's interesting, because I have a mate who does much the same job, and he's still happily navigating with his GPS! I understood they'd only turned the 'wobble' back on over Afganistan kind of area, and the rest of the world was OK.

And in reply to the rest of the world.....

My experience of GPS and Cairngorm whiteout is that it was very accurate. Having paced around in 100m legs for about 2 km, then done a line search to locate a gully shown on the map, we stopped for lunch. Out of interest, we turned on the GPS, which gave a position as accurate as you could locate on the map. Pretty useful for finding yourself should you happen to have got yourself properly lost! (Though, as Pete A says, I'd be quite happy with a GPS that just gives me a grid ref - I'm not sure I've used any of the other features). Mind you, the batteries don't much like the cold, so there's a lot to be said for keeping it in a jacket pocket where it stays a bit longer. BUT....... it might affect your compass if turned on!!! I found up to a 20 degree deflection of the compass needle with the GPS on in a chest pocket, and holding the compass at that kind of height to walk on a bearing. Quite enough to ensure you get lost in the first place......

In reply to ice:
Not having a GPS doesn't stop people who can't navigate going on the Glyders..... I've been with a group on a navigation assessment, who spent ages looking for a trig point on the top of one Glyder........when in fact they were on top of the other Glyder!

And in reply to Taki:
Just to give you some idea of a Scottish whiteout, the day I tested my GPS, someone managed to crash a small plane within 200m of where we walked. We were totally unaware of it, and the associated rescue, until we got back down. They found the folks from the plane, who'd gone on a wander, but didn't find the plane itself for another couple of days as the weather didn't improve. I don't think I fancy sitting still for that long!

In reply to ejstubbs: i don't know about you, but just looking at a bunch on numbers on a GPS isn't going to make me feel better about where i am. so its still a tool, you still need common sense, a map and a compass to locate your self. you'll also have to consider the terrain. if you can locate yourself with map and compass by triangulating or something, i think its more worthwhile. but then, it can depend of when the maps are printed. sometimes things appear since the printing of the maps, especially man-made features. again, like i said, having a GPS, in itself will not get you lost. it can tell you where you are, but unless you have a marked waypoint to the trailhead or something, its not going to get you back to a known location, sans map and compass.

the canyons of the southwest. they are basically cracks in the earth, which can be quite deep and narrow, not wide enough for sat signals to reach in. kinda like trying to use your GPS unit in a densely constructed areas with high buildings. unless you have a bird directly overhead (of course you need at least 3 or 4) its not going to do you any good. better to keep your self known than rely on map and companss when you're lost. besides, in such areas, there can be features that aren't on the map, again, if the map's old, what not. every year people die from flash floods, sometimes bodies are found several miles from the incident. its quite scary, since it could be raining several miles away, you could be quite unaware, and before you know it, you hear the thundering noise of a thick, heavy mixture of mud and water coming at you. in such terrain, you have to keep a mental note of where your last escape was, or you're really screwed.

i'm sure if you have a look around on the web, you'll find plenty of nice pics... shouldn't be that hard.

thanks for the input

btw, i have a GPS unit, but rarely use it. much easier using a map and compass. i'd consider using it in a desert environment, or anything similar in terrain (open prarie, or open seas, that sorta thing)

In reply to Taki:

"i'd consider using it in a desert environment, or anything similar in terrain (open prarie, or open seas, that sorta thing)"

I think that's the crux of the matter - the Cairngorm plateau in a whiteout comes into the same category, in my view. You've basically got a flat piece of ground, with almost all the features hidden under snow, and steep cliffs off some sides. In low cloud and falling snow, you might not be able to see much more than 10m - or be able to tell if the ground in front of you goes up or down. Not a good place to be 'lost'!

I don't think that anyone would disagree that the best plan is not to get lost in the first place. Or that a map an compass, plus the ability to use them, are essential. But if you do get lost, triangulating isn't going to help much. Nor are other skills, like determining the aspect of slope, or walking to a handrail feature. To be honest, it can be much like trying to re-find yourself whilst blindfold! Or, indeed, in the middle of the sea with nothing in sight.

Personally, I was pretty pleased to know that the series of numbers agreed with where I reckoned we were, and means I'd be more tempted to trust it if really lost...... which I don't intend to be! Given any other features, I'd prefer t use them....... but in their absense, GPS ain't bad.

Equally, I'd agree with you that GPS isn't likely to be much use in a canyon. They sound like fantastic places, BTW.

PS Tried to find a piccy of a Cairngorm whiteout on the web, but failed...... will try and remember to bring one in to scan. Or should I just use photoshop?

In reply to Carolyn:
If you look closely, you can see that, in fact, that the background picture for this whole thread is a photo of a Cairngorm whiteout !

In reply to Taki:
People used to wander the hills without any navigational aids. Then, they decided maps would be useful, so people started to carry a map. The same happenned with a compass. I'm not aware of any major outcry about people using maps & compasses. So why the big deal about GPS?

Yes, it is exceptionally important to learn how to use a map and compass, as they are your primary navigational aids. GPS is just an excellent back up.

So if you have one, learn how to use it and put it in your rucsac. If you get lost using Map & compass, or unsure of exactly where you are, then use the GPS and return to your map and compass. What's the big deal?

In reply to Martin P: GPS just seem to take all the fun out of navigation. Give me an old compass any day. Problem people have is that they don't know how to use compasses properly.

In reply to bob: i don't know where people get the idea that i've said it was a bad thing. all i've said was that its a tool, and you shouldn't depend on it too much. before depending on such devices, one should be competent with a map and compass. what' so wrong about that?

there's no bid deal, but some people think there is, for some reason unknown to me

In reply to Steve:

Gosh, you're right!

It loses its effect in a picture, doesn't it? I didn't spot it 'cos I wasn't being blown over or squinting to keep the ice out me eyes......

In reply to Carolyn:
Just had to put my goggles on to read this page. Phew! Thats better!

In reply to Taki: Hmm, your canyons sound..."interesting"!

You say: "having a GPS, in itself will not get you [un]lost. it can tell you where you are, but unless you have a marked waypoint to the trailhead or something, its not going to get you back to a known location, sans map and compass."

I think it's a bit like that Microsoft joke; the one about the guy who's trying to land his plane in Seattle but he's lost in thick fog. He sees a tall building through the murk, and flies round it until he spots a chap next to an open window.
"Excuse me," he asks, "can you tell me where I am?"
"You're seated at the controls of a light aircraft which is flying past the 20th floor of an office building."
"Thanks mate, that's great!"
Twenty minutes later he's landing safely at Seattle airport.
"How on earth did you do that?" asks his passenger.
"Easy," says the pilot, "what he told me was completely accurate, but no use whatsoever. That meant that he worked for Microsoft tech support, and their building is ten miles north-west of the airport."

It's the same with GPS: it can give you remarkably accurate information, but without knowledge of the context (ie a map), it's of strictly limited use.

Agree with you that map and compass are actually easier to use than GPS in most cases. I do worry about my mate who trudges along ridges with his eyes glued to his GPS, but then I've got the map so we still get up and down OK.

In reply to ejstubbs: i guess a few people have shown interest in the canyons of the american southwest... i'll try to find something on the web, and i'll post it. just bear with me.

heres a few (with pics)
http://climbutah.homestead.com/
http://www.canyoneeringusa.com/utah/

i guess there's others, but they didn't seem to have good pics. i guess they'll kinda give you an idea of what the canyons are like... and why GPS won't work, and also why there's a constant flash flood danger.

personally, cedar mesa in utah's been my favorite...

In reply to Taki: Impressive stuff! Thanks for seeking these out, Taki.

In reply to MartinW: don't worry about it... just did a quick search on google for canyoneering. if anyone's interested, give it a go. its quite interesting, to say the least.