 Poster: A snowHead
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| So how do you utilize your map in zero vis, \'when the mist comes in\'? |
PJSKI Do you have jedi-force and a special 6th sense that allows you to navigate with out a map ?
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Not on an Iphone it isn't which was my point.
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As I said, get a proper GPS! But you can get a proper reference from an iPhone with most navigation apps. And lat/long is still perfectly accurate, just means an extra step to plot your position.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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| Haggis_Trap wrote: |
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| So how do you utilize your map in zero vis, \'when the mist comes in\'? |
PJSKI Do you have jedi-force and a special 6th sense that allows you to navigate with out a map ? |
ifirc he has a special jacket 
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| stevomcd wrote: |
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So how do you utilize your map in zero vis, 'when the mist comes in'?
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On skis/board, I wouldn't be referring to the map constantly, but I'm very confident I could still give an acceptably accurate reference even in poor visibility. GPS, if available, would
obviously be helpful in this situation - but I would always sense-check a GPS reading against my own calculated reference. |
Using what methodology?
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Do you know the local french name for Stairway to Heaven Because Stairway To Heaven is very much the anglicized name.
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You mean that isn't what the Swiss call it [/feigned surprise]
I don't speak fluent French but I'd be ok to give my altitude and my position relative to the Gentianes cable car wires. That said, I've almost always got the 1:25 with me if I'm doing anything serious and yes, I can navigate fairly well in the mountains. I'm not saying don't equip yourself properly, just do what's fastest when you are in the situation you are in.
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| scottishskier wrote: |
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A GPS position, both in France and in the UK, IS a map grid reference!
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Not on an Iphone it isn't which was my point. |
In what way is it not a proper grid reference on an iPhone?
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| Haggis_Trap wrote: |
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| So how do you utilize your map in zero vis, \'when the mist comes in\'? |
PJSKI Do you have jedi-force and a special 6th sense that allows you to navigate with out a map ? |
So how do you utilize your map in zero vis, 'when the mist comes in'?
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Using what methodology?
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In that situation, you'd have to base it on dead-reckoning from your last-known position, combined with observation of the terrain you've travelled over and any terrain feature that you are able to see (e.g. if you're in a gully, on a ridge, on a small summit, etc.).
E.g. "I dropped in from the summit of Le Fogliettaz. We rode the first pitch, then bore left to avoid the cliff bands. That's where we entered the clouds and visibility got bad. We dropped into the gully to the left of the main pitch and we're now just at the point where the steepness of the terrain starts to mellow-out."
If you can read a map, you can use the thought-process above to give a pretty accurate reference. In this example, you would know roughly where you were, and you could then use the combination of the gully with the change in contours denoting the change in steepness to give your position to an accuracy of probably better than 100m or so (which is as accurate as you can ever be with a 6-figure grid ref anyway).
This isn't being an armchair smart-ar$e or wishful thinking, this is basic navigation and it works.
If you have no idea where you've been all-day, have been muddling around in bad visibility for a long time and then decide to pull a map out to figure out where you are, then you're a muppet and god help you!
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You'll get to see more forums and be part of the best ski club on the net.
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PJSKI How do you navigate without a map ?
This fourm needs an injection of TGR style self policing.
i.e So why dont you STFU JONG! Rather than fishing for a debate / bun-fight.
Fyi I would ideally use a GPS to confirm where I thought I was on the map.
However GPS reference alone, without a map, is totally useless.
(many people people still safely navigate using traditional map and compass techniques).
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| stevomcd wrote: |
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Using what methodology?
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In that situation, you'd have to base it on dead-reckoning from your last-known position, combined with observation of the terrain you've travelled over and any terrain feature that you are able to see (e.g. if you're in a gully, on a ridge, on a small summit, etc.).
E.g. "I dropped in from the summit of Le Fogliettaz. We rode the first pitch, then bore left to avoid the cliff bands. That's where we entered the clouds and visibility got bad. We dropped into the gully to the left of the main pitch and we're now just at the point where the steepness of the terrain starts to mellow-out."
If you can read a map, you can use the thought-process above to give a pretty accurate reference. In this example, you would know roughly where you were, and you could then use the combination of the gully with the change in contours denoting the change in steepness to give your position to an accuracy of probably better than 100m or so (which is as accurate as you can ever be with a 6-figure grid ref anyway).
This isn't being an armchair smart-ar$e or wishful thinking, this is basic navigation and it works. |
Do you think this is where an accurate measurement of hight comes in, so you can work out what contour line you're on?
You're not coming across as a smart-ass at all. More like someone who knows what he's talking about.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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| stevomcd wrote: |
| If you can read a map, you can use the thought-process above to give a pretty accurate reference. In this example, you would know roughly where you were |
The one thing which struck me when I've done navigation training is it's a constant process of observation and double checking whatever landmarks you can reference on the map, whether they be obvious points you can take a compass reading off or small scale terrain changes. By doing this it is straightforward, although requires some skill, to navigate in poor seeing conditions. I suppose this is much the same for reading snow conditions: you have to be constantly looking for all the indicators you can see, rather than just ignoring them then trying to make a spot decision when you're at the top of a slope.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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^^^ an accurate altimeter is incredibly helpful in those circumstances
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Do you think this is where an accurate measurement of hight comes in, so you can work out what contour line you're on?
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Yes, an accurate altimeter would be really useful in that situation. If you're on some kind of linear feature (e.g. gully, ridge) then having an altimeter alone is enough to give you a very accurate position. Obviously less use on a big flat plateau or similar.
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You know it makes sense.
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| Arno wrote: |
| ^^^ an accurate altimeter is incredibly helpful in those circumstances |
Agreed. When I did the BASI mountain safety we were allowed an altimeter but not a GPS, so had to pay a bit more attention to traditional navigation skills.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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| Haggis_Trap wrote: |
PJSKI How do you navigate without a map ?
This fourm needs an injection of TGR style self policing.
i.e So why dont you STFU JONG! Rather than fishing for a debate / bun-fight.
Fyi I would ideally use a GPS to confirm where I thought I was on the map.
However GPS reference alone, without a map, is totally useless.
(many people people still safely navigate using traditional map and compass techniques). |
My primary method of navigation is visual. But I do carry map, compass, GPS and a barometric altimeter. I don't do much in the way of exploring, so the map remains secondary and it would only come out if something went wrong.
Is a map your primary way of navigating in the mountains?
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Poster: A snowHead
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In my local area, where I know where I'm going, I don't use a map very much, just have it there as a back-up.
If I'm going somewhere new, or just doing a route I haven't done before, I'd always plan it on the map, then navigate visually unless it was really complicated.
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Agreed. When I did the BASI mountain safety we were allowed an altimeter but not a GPS, so had to pay a bit more attention to traditional navigation skills.
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IML is the same, altimeter but no GPS. I can't quite remember if you're even "allowed" an altimeter at ML level. Think you are, but you're much more encouraged in its use at IML.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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| stevomcd wrote: |
In my local area, where I know where I'm going, I don't use a map very much, just have it there as a back-up.
If I'm going somewhere new, or just doing a route I haven't done before, I'd always plan it on the map, then navigate visually unless it was really complicated. |
Yep, that what's I do. Those Jedi senses are very handy.
Last edited by Obviously A snowHead isn't a real person on Thu 13-01-11 12:44; edited 1 time in total
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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stevomcd, if you did your ML stuff in Scotland, I'd imagine you'd need to have approached altimeter readings with great care!
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Arno, I'm told the area of the Monadh Mhor where we did our assessment is known as "the ML graveyard"!
BTW, got the transceiver the other day, thanks a lot (with the holiday season and how busy we've been it took me a while to get to the post office!). Just what I needed.
What happened to it out of curiosity?
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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As I understand it from reading various internet articles and therefore being an expert  , if a burial victim is wearing a transceiver, the locating phase is generally shorter than the digging/extraction phase. Furthermore, death is likely to be from asphyxiation, ie lack of oxygen due to depletion of the air in the snow matrix close to the victim. Is there any mileage in the thought of ‘buying time’ by supplying air to the victim whilst the dig is going on. Picture a hollow avi-probe with a set of holes at the bottom and the means to attach a simple pump (bicycle pump?) to the top. Once the victim has been located with the probe, attach pump and operate to create/keep a bubble of cleanish air close to the victim. Obviously, this would be done such that it wouldn’t slow down the digging effort. Thoughts?
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MontriondSkier,
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Furthermore, death is likely to be from asphyxiation, ie lack of oxygen due to depletion of the air in the snow matrix close to the victim.
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No, death is likely to be from asphyxiation due to the inability of the victim to expel CO2 from around their face.
In reply to everyone: IMO there is nothing scarier than people who have hard fast rules and "the way" of doing something in a fluid situation.
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| MontriondSkier wrote: |
| Thoughts? |
How would you know where the victim's mouth was? Pointless pumping air to them unless it's very close to the mouth. What would happen if the victim's airway was blocked by snow? Would an extra metal probe get in the way of digging?
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Swirly, I don't disagree with you, but having been unfortunate enough to have been in a couple of real situations, having a plan and a procedure to follow is a good thing when there is likely to be a lot of panic going on.
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You'll get to see more forums and be part of the best ski club on the net.
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stevomcd, I agree but that's different to sitting in front of a computer saying you should do this.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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stevomcd, although it would be nice if they really had been shown to save more than a few lives...
MontriondSkier, I am sure you have seen this already?
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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stoatsbrother, agreed, I have one but don't use it as it's a faff to wear along with a pack and, as you say, they're not very well-proven.
Although some day I must go out with transceiver, ABS, avalung, avalanche ball, avalanche cords, helmet, body armor, harness and 10ft long pole strapped to my back (so I don't fall down crevasses) just for the look of the thing...
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Swirly - Asphyxiation is defined as a lack of oxygen to the brain and can be caused by crushing the chest to physically stop breathing or by having a low oxygen atmosphere, ie air that has been continually rebreathed. Hypercapnia (too much carbon dioxide) will cause rapid breathing, etc. but will not directly cause death until the concentration is extremely high. These semantics are however rather irrelevant; whatever you call it, a buried avalanche victim rebreathing the same air will die. Supplying that person with clean air will buy time. This is the principle behind the avilung. Could it be achieved externally?
If the probe was inserted into a clean homogenous snow pack, the air pumped in would spread out evenly in all directions forming a spherical ‘bubble’ round the tip of the probe. If the snow were compacted in one area the bubble would be distorted with the air following the paths of least resistance. If there was an air pocket it would travel much more freely through the crevice that through the matrix of snow. If the probe were in contact with the victim then I hypothesise that the air would preferentially flow in the crevice between the body and the snow matrix. The hope would be that the free air would displace the depleted air and help the victim. Obviously if the probe was in contact with the foot it would be less effective than if it was in contact with the shoulder. I am interested to hear if this has been tried/tested before?
Would the probe get in the way? The advised technique is to start digging approx 1.5 times the burial depth downhill from the probe used to locate the victim. If the probe used to find the victim doesn’t get in the way of the dig, why should any additional probe used to supply air get in the way. In principle they could both be the same probe.
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You know it makes sense.
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| In what way is it not a proper grid reference on an iPhone? |
I don't own and haven't used an iphone much but I think without specific apps it will only give you lat/long which most search and rescue teams won't take. You need the lat/long converted to a 6 digit grid reference specific to the country you are in.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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MontriondSkier, one of the issues is that when a victim exhales the moisture in his breath freezes on the snow around his mouth/nose forming an impermeable layer (there is a bit of jargon for this which I forget). There is plenty of air in the snow but this impermable layer prevents a victim from using it. The avalung works on the basis that it allows you to continue to breath the air in the snow
stevomcd, i don't know whether the bleeper had already been weakened by something else but i had my camera in a pocket near the bleeper. i bent down to undo my boots, heard a crunch and the case had caved in! it was a powder day on the Grands Montets so a duct tape repair and a quick test suggested it was still transmitting so i took a deep breath and kept on skiing
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Poster: A snowHead
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| scottishskier wrote: |
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| In what way is it not a proper grid reference on an iPhone? |
I don't own and haven't used an iphone much but I think without specific apps it will only give you lat/long which most search and rescue teams won't take. You need the lat/long converted to a 6 digit grid reference specific to the country you are in. |
OK, I understand. I use a GPS application which does just that (selectable to different grid reference systems), as well as being able to download topo and road maps to it. Perhaps not as good as a dedicated GPS unit and not a replacement for a topo map, but useful as a backup not least because I always carry it.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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scottishskier, I don't think it would be a case of rescue teams "not taking" a lat/long reference. If that's all you've got, they'll take it, but it's obviously not ideal.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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MontriondSkier, you may well get ice masking over the victim's mouth and nose. One of the reasons the Avalung works is that it helps prevent this.
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MontriondSkier, ^^ what Arno said. You'd have to get the probe to the victims mouth to penetrate the ice that forms from the condensation of their exhaled breath.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Never having been buried by snow I don’t know, but I would suspect that in most cases there would be some degree of air gap between the face and the snow matrix. Some claim that the snow sets like concrete but most advice includes trying to create an air space in the seconds after coming to rest, presumably by moving the head as much as possible. If the matrix really was close across the face then I concede the air flow from the probe may not be able to get to the airways due to the condensation/freezing mechanism. I guess the only way to prove the idea would be to try it. Volunteers to be buried anybody? 
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MontriondSkier, Problems with this are 1) The buried victim may actually be head down and vertical, or horizontal and face down. 2) It is difficult enough pin-pointing a whole body let alone a head. 3) all this subtracts time from what is proven to work, digging in an organised fashion from downhill of the victim, not standing on him, and when you can see which way they are pointing, prioritising getting to their airway first.
One interesting point the bloke who sold me my new snowpulse made is that if you are competely buried with that deployed -it is partially permeable and filled with compressed air - effectively increasing your air space by 150L. Whether this is proven is another matter.
Dislcaimer: I am probably the least expert person posting on this thread.
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So regarding the map, I am being very serious. I don't ski off piste with one.
However I suspect my definition of off piste is different to you guys who carry a map! Mine will be (or has been so far) lift served, where I am within 5-30mins ski from a lift or piste. If I have gone further afield I have taken a guide.
So far I have not walked/skinned/heli'd miles from civilisation and therefore have not needed a map to get in or out of the area.
I don't think I have ever skied anywhere off piste where I didn't know a route out/back to a lift/piste in case of an emergency, or if the weather came in.
Hopefully that makes sense???
cheers,
Greg
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kitenski,
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If I have gone further afield I have taken a guide.
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So, if further afield, you'll presumably be stuffed if the guide happens to be the one to be taken out?
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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| kitenski wrote: |
So regarding the map, I am being very serious. I don't ski off piste with one.
However I suspect my definition of off piste is different to you guys who carry a map! Mine will be (or has been so far) lift served, where I am within 5-30mins ski from a lift or piste. If I have gone further afield I have taken a guide. |
30-minutes is a relatively long distance for lift served off-piste, so I would very definitely suggest taking a map.
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| stoatsbrother wrote: |
MontriondSkier, Problems with this are 1) The buried victim may actually be head down and vertical, or horizontal and face down. 2) It is difficult enough pin-pointing a whole body let alone a head. 3) all this subtracts time from what is proven to work, digging in an organised fashion from downhill of the victim, not standing on him, and when you can see which way they are pointing, prioritising getting to their airway first.
One interesting point the bloke who sold me my new snowpulse made is that if you are competely buried with that deployed -it is partially permeable and filled with compressed air - effectively increasing your air space by 150L. Whether this is proven is another matter.
Dislcaimer: I am probably the least expert person posting on this thread. |
Interesting... I wonder if there might be a way, in the even of a burial, to use the air in an airbag to increase how much air you have to breath before it gets too CO2 tainted? What gas do they use in the airbags?
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