Messages posted by : ise
Profile for ise > Messages posted by ise [1815]
And I was going to comment on that. For those that weren't there, bandit was skiing towards me slowly and I moved my Tracker to receive. This is a standard "ski by" transceiver test, people often stand by each other and check which is good but this is better, the idea is you can pick the other person up at around 30m and they move towards you etc, it's a good range check for the transceiver. What happened the other weekend though was as bandit closed the distance my receiver leapt about 1.5 m away from here signal. That's consistent with the reported problems with mobile phones so I asked if bandit had a phone. What's interesting there is that you're only 100m from the phone mast so is the signal stronger or weaker? I did subsequently wonder if you'd hit a flux line though and that's what happened although I don't think I've seen that happen on a "ski by" before. |
|
technical correction... it's just struck me that the helicopter mounted receivers with the dish at the front of the heli' may receive at that distance. So, technically we are transmitting a fair way but the receive range of a hand unit is lower, say 40-60m approx |
|
:oops: long posts are horrible I know, but I think I just described this. If you want the executive summary, RECCO detectors are great for recovering bodies. There's practically no recorded live recoveries. |
|
|
gavin2020 I've taken a couple of your comments from the thread about RECCOS because I think they're worth some more comment and that it's a pretty important thing to understand. It looks a bit like I've singled you out there for which I'm sorry, I think you're obviously thinking about the hazards and what you can do about them and that's a really, really good thing.
If your practice isn't taking more than a few minutes then I've got to say that you're not testing realistic scenarios. We ran an exercise yesterday with multiple burials in a steep slope (in excess of 45') include one burial at nearly 2m and it's simply not possible to locate beacons in a couple of minutes in these conditions. Unless you test and practice in these conditions then you're not really fully prepared. Burying transceivers in snow near the piste is good practice but you need to build that scenario to being on a 30' plus slope up to your waist in snow with multiple burials. Until you move to that type of terrain you're effectively practicing in two dimensions alone, it's gets very 3D on a steep slope.
Anyone that runs scenarios in the conditions as I've described doesn't share that peace of mind I'm afraid. Yesterday even though we pulled the first burials out in under 12 minutes it was a full 38 minutes before we'd located and pulled out the deep burial. As searchers we'd both got some previous advanced training in avalanche awareness and snow analysis, we had state of the art equipment and some experience using it. You absolutely cannot get peace of mind from that experience, the only possible conclusion you can get is that you never, ever want to do it for real. There's a whole series of common denominators for fatalities in avalanches and one of them is a perception of awareness of risk from the victims, an unrealistic confidence in their ability to analyze snow stability and an unrealistic confidence in their ability to use transceivers. We all (I include myself) need a reality check from time to time on this really. What this means is that typically when interviewed surviving members of a party nearly always know the avalanche risk that day, are carrying transceivers and material, have practiced with that material etc. It's rare that they are not equipped or can't use the material and oblivious to the risk as we like to think Take a look here : http://www.slf.ch/avalanche/avalanche-en.html and follow the links for previous accident reports. Take note how long it takes to locate victims at various burial depths. Again, it's just great that you're practicing with the beacons but if you think you can locate victims in a few minutes you really need to think again. I highly recommend taking real training and I recommend particularly these people : http://www.alpineguides.info They're very good and members of the Leysin Rescue team as well with real experience. That's who I was with over the weekend in fact (http://snowslider.net/) I absolutely know how this works, everyone's aware of the figures, 75% of people die from asphyxiation, of the those buried that survive initial trauma 92% survive if recovered in under 15 mins, people take that 15 minute figure, bury a transceiver, find it in around 10 mins and are confident they're safe, it's just not true though. |
|
As they weigh practically nothing and cost about the same there's no strong reason not to have them. It's just a copper coil with a transponder and a diode basically but it's actually highly accurate, as it's not transmitting a detector will go straight to a transponder without traversing flux lines as in a transceiver search. It's a passive system and doesn't interfere with anything else. The typical use is from helicopters and the detectors can pinpoint other devices like phones, radios or transceivers even if they're turned off. In terms of a primary system it's not so good, a lot of ski stations do have detectors but getting them or a helicopter on scene takes too long for them to be useful. Here in Switzerland the main rescue helicopters, Air Glaciers, REGA and Air Zermatt have detectors as do the PGHM in France. The chances of being found with a RECCO are fairly remote, in the last few years in Switzerland I think there's only been one recovery (deceased) made with a RECCO out of about 100 and that was in Zermatt. I'm not even sure why RECCO was deployed for that incident, the recovery was 23mins at 140cm which suggests it was near a detector cache or Air Zermatt were in the air very quick and that the skiers weren't equipped with transceivers. In terms of overall effectiveness I'm not sure there's any systematic data collection especially for live recoveries, but, I'd think the live recovery number is vanishingly low. There's an argument that placing them in jackets and on gear puts them into groups that wouldn't typically have any active detection but it's a poor argument at best and not helped by a lack of recorded live recoveries.
It's worth bearing in mind if you decide to use RECCO's then you'll need more than one, the signal can be blocked by the body so having them on both sleeves and boots is a good configuration. Do I have them? No, I had to pause and think if any had snuck onto jackets etc and they've not and if someone gave me a handful I'd probably not put them. I'm fairly ambivalent if it's a dog or RECCO that recovers my frozen body, I'd go for the dog on balance, I think there should be more dogs for SAR work. What do I carry though? In order of likelihood : A tracker DTS transceiver G3 Avitech shovel G3 speed pro 240cm probe slope meter G3 bone saw G3 rutsch block cord thermometer crystal card magnifying glass EITHER avalung OR abs sack Anyone off piste should have the first three items minimum and know how to use them of course.
That'll be for an ipod or phone. You would not put a transceiver in a pocket like that.
First, you're talking transceivers, there's no transceiver on the marker with a range of 200m, you may be using the wrong units and mean 200 feet which is more realistic. Second, it's not mandatory to wear transceivers anywhere to my knowledge even in the US. There are out of bounds areas with gated access tripped by a transceiver signal or with test zones on the gates. It's just strongly advised. Third, you need to understand not everyone's in the US or skis there. US stations have avalanche controlled off-piste inside the station boundaries, that's not generally the case in Europe although exceptions would be any itinerary and specific areas like the SPOT in Tignes and our Freeride area in Zinal. It is common practice in the US not to carry transceiver/probe/shovel when skiing lift served off-piste as it's controlled, that's not the case in Europe (see above exceptions) and anyone skiing off-piste needs to carry minimally transceiver/probe/shovel and be proficient in their use. Finally, phones are useful but can't be used in combination with transceivers, the transceiver signal is deflected by the phone. |
|
Good tips, it might be worth also checking your car manual as well. Tests show that chains and some traction control systems don't interoperate properly and some need turning off. In fact that's true without chains at least moving off on ice sometimes, the sliding Laguna I mentioned the other day had that problem it turned out, I found the switch to turn the traction control off and we got moving properly in the end. |
|
absolutely, people seem to miss that fact. We buy winter tyres at the first winter when we get the car and the two sets last until we change the cars. |
|
There's a bunch of scenarios presented and I recognise some elements of that. Some ocean currents, Gulf stream and the North Atlantic Drift have warming effects on nearby landmasses. Without those currents those landmasses would cool, probably by a couple of degrees. The salt content, IIRC, is effected by evaporation as these flows move, so the present effect is to increase salinity, consequently without the flow salinity would decrease. But, IIRC, a more immediate issue is actually increasing salinity in tidal estuaries etc. I'd not assume just because it's colder on average it's going to benefit winter sports, you'd need a low variance as well and precipitation of course. |
|
Profile for ise > Messages posted by ise [1815]