Personal Locator Beacons (Spot, InReach, etc) in avy terrain

[Monique]

When reading this post about a Colorado avalanche fatality, I wondered if a PLB would have helped. I also wonder if they interfere with transceivers. I would think they must, so you likely wouldn't want a PLB powered except to use in an emergency ... right?

This is in NO WAY a criticism of the skiers, who were clearly well prepared - just a thought. While it would not have prevented the incident, a Garmin InReach, Spot, or similar might have allowed them to contact emergency services much more quickly. Of course I have no way of knowing if that would have mattered in this case. They're expensive to purchase and require a service plan. But even in a gully like that, such a device would have a good chance of sending an SOS signal quickly and would exactly pinpoint their location for SAR.

I have an InReach. It feels like overkill, and I felt particularly silly grabbing it when I was skinning up a popular XC trail last weekend, but I would feel even sillier if it were in the car and I needed it for myself or someone else. How many of you have a satellite phone or text device like the InReach or Spot? When do you bring it with you? If you don't have one - if it money were object, would you have one?

 

[mikel]

I also have InReach. I never feel like it's overkill. It's in my pack along with my beacon. There are times that I also have my 2m/440 hand held with me. CO has pretty good repeater coverage. No such thing as being over prepared when it comes to the back country winter, summer, or fall.

no need to worry about plb's and intereference

 

[Joel]

I have a Spot that I have for my sailplane. I thought about using it when Im out skiing. When it comes to the case of being burried in an Avalanche my thoughts were that it would not be useful. I dont think a signal would get out and you have to manually activate it. After reading a lot more about BC safety, I am starting to reconsider this. There are other things that can happen that the Spot just might be good for. The Spot also has other messaging features that could be useful. Given that my Cell is useless for texts or calls, my Spot might not be a bad idea.

Ham handheld is also not a bad idea. Might rethink that as well.

 

[Mike King]

I have a Spot that I have for my sailplane. I thought about using it when Im out skiing. When it comes to the case of being burried in an Avalanche my thoughts were that it would not be useful. I dont think a signal would get out and you have to manually activate it. After reading a lot more about BC safety, I am starting to reconsider this. There are other things that can happen that the Spot just might be good for. The Spot also has other messaging features that could be useful. Given that my Cell is useless for texts or calls, my Spot might not be a bad idea.

Ham handheld is also not a bad idea. Might rethink that as well.

Joel, I think the idea is to use the device to summon help, not to locate a buried individual. The parties in the red mountain incident had trouble summoning help because they couldn’t get a cell signal.

 

[Joel]

I am usually alone when I ski, I was talking about the specific case where I get burried that I didn't think it would be useful. But the other cases are why I'm rethinking this, there may be other circumstances for myself that it could be useful, or, even though I ski alone, there could still be a situation that a radio or my Spot might come in handy to help someone else. The Spot is certainly not big, no reason to not just have it.

I guess the bottom line is, I always have my backpack, this stuff is small and should just be part of my kit.

Joel, I think the idea is to use the device to summon help, not to locate a buried individual. The parties in the red mountain incident had trouble summoning help because they couldn’t get a cell signal.

 

[at_nyc]

My problem with "emergency electronics" is, these gadgets sits in the pack for months and years. They don't get used till they're needed. You need to inspect them to make sure they're charged. Charge them when they lose enough of the juice. I know I'm not diligent enough to do that. That's why I'm not too motivated to acquire more of such gadgets.

 

[Pequenita]

no need to worry about plb's and intereference

Why not?

 

[SBrown]

If you really want to get into it, this paper was interesting: http://arc.lib.montana.edu/snow-science/objects/ISSW13_paper_P1-34.pdf

 

[tball]

I think it would great to have a PLB even where there is good cell coverage.

911 cell location is unreliable. Saw this on NBC Nightly News the other night, reporting from Arvada a nearby Denver suburb:


Having a PLB for inbounds skiing even seems like a good idea. For mountain biking and hiking, why not other than cost?

 

[Monique]

no need to worry about plb's and intereference

Why not?

My problem with "emergency electronics" is, these gadgets sits in the pack for months and years. They don't get used till they're needed. You need to inspect them to make sure they're charged. Charge them when they lose enough of the juice. I know I'm not diligent enough to do that. That's why I'm not too motivated to acquire more of such gadgets.

I keep mine turned off in the center console of my car. It loses charge very, very slowly - maybe 25% in a month or two - and is chargeable via USB, so I can just plug it in periodically. There's a (relatively) cheaper emergency plan if you don't want all the fancy tracking features. Not that I'm saying this would work for you - this is how I use it. I will definitely be on a trail at least once a month (typically much more often), so for me it's not hard. I also have used it in a cell phone dead zone on I-70 to ask a friend to find out why traffic was at a stand still ....

Having a PLB for inbounds skiing even seems like a good idea.

I've thought about this, but haven't done it yet. Maybe if I'm skiing alone it would be much smarter. I carry a beacon and a whistle. Even my "secret stashes" aren't far from well traveled terrain, and locals are in those stashes anyway. My main reason not to is simple logistics - all my pocket are already stuffed full.

 

[Joel]

It's the frequencies the devices work on. Avalanche beacons are on 2.275KHz, my Spot ( PLB ) for example is 1.6GHz, the HAM radio I could carry is 50MHz, 144MHz, 440MHz. All of these are very far away from each other. If well designed ( I expect so, just to pass certification ), they are not likely to interfere with one another.

Why not?

 

[Monique]

If you really want to get into it, this paper was interesting: http://arc.lib.montana.edu/snow-science/objects/ISSW13_paper_P1-34.pdf

Thanks!

The especially relevant part seems to be in this list of items known not to interfere with *send* function when *turned off* and 20cm from the body. (I think I got that right - no one should rely on my interpretation - read the article for yourself!)

cellular phones, satellite phones, PLB (personal locator beacon) (inference may occur during communication (incl. synchronization with the network, communication of text messages and data), devices need to be turned off during search for all searching rescuers. As long as the search is in progress, use of these device on the entire avalanche should be restricted to short-lasting emergency calls in minimum distance of 25m to the closest searching rescuer. Based on new measurements, actively searching rescuers must completely turn off cellular phones as some specific, but popular models show even in “air plane mode” in distances up to 100cm interferences which trigger erratic distance / direction indications on the screen in areas where there is no real transceiver signal).


I also hadn't considered the impact of wearing my Garmin watch with Bluetooth enabled while carrying a beacon ... will have to read the article in more detail to fully understand consequence and mitigation. Fortunately, it's on my left hand, not my dominant right hand.

 

[Joel]

There are different battery technologies, all with pluses and minuses. For storage NiMH are probably near the worse, NiCD you don't see much anymore. Lithium of some flavor are pretty good for low self discharge. There are some LSD ( Low Self Discharge, OK... ) NiMH but I don't find them adequate to trust.

My Spot - Alkaline batteries, new ones each season if I'm going to use it. Will probably look into Lithium cells for it ( single use type )
GPS - rechargable LSD NIMH. I carry a set of Alkalines in my pack for it as back up.

Yes, there is an effort to battery management, just got to do it. For seasonal stuff, take the old ones out at the end of season, put new ones in at the beginning.
For rechargeable stuff, most chemistries have a storage voltage they like to be at. Learn what it is and do it, they will last longer.

Taking care of batteries should not be a deciding factor for safety.

My problem with "emergency electronics" is, these gadgets sits in the pack for months and years. They don't get used till they're needed. You need to inspect them to make sure they're charged. Charge them when they lose enough of the juice. I know I'm not diligent enough to do that. That's why I'm not too motivated to acquire more of such gadgets.

 

[at_nyc]

There are different battery technologies, all with pluses and minuses. For storage NiMH are probably near the worse, NiCD you don't see much anymore. Lithium of some flavor are pretty good for low self discharge. There are some LSD ( Low Self Discharge, OK... ) NiMH but I don't find them adequate to trust.

My Spot - Alkaline batteries, new ones each season if I'm going to use it. Will probably look into Lithium cells for it ( single use type )
GPS - rechargable LSD NIMH. I carry a set of Alkalines in my pack for it as back up.

Yes, there is an effort to battery management, just got to do it. For seasonal stuff, take the old ones out at the end of season, put new ones in at the beginning.
For rechargeable stuff, most chemistries have a storage voltage they like to be at. Learn what it is and do it, they will last longer.

Taking care of batteries should not be a deciding factor for safety.

All that, is ON TOP of charging your phone, your beacon, and maybe your GPS (if you carry one). It's just too much battery care for me.

 

[SBrown]

It's the frequencies the devices work on. Avalanche beacons are on 2.275KHz, my Spot ( PLB ) for example is 1.6GHz, the HAM radio I could carry is 50MHz, 144MHz, 440MHz. All of these are very far away from each other. If well designed ( I expect so, just to pass certification ), they are not likely to interfere with one another.

But it isn't only that. From the referenced paper: "Metal parts, magnets and any kind of passive or active electronics potentially cause interference for a transceiver."

 

[Joel]

That was an interesting read, and does correctly err on the side of safety. I missed the newer Avy beacon frequency. Now I might just have to get one just to test how much of an issue it really is.

Thanks!

The especially relevant part seems to be in this list of items known not to interfere with *send* function when *turned off* and 20cm from the body. (I think I got that right - no one should rely on my interpretation - read the article for yourself!)

cellular phones, satellite phones, PLB (personal locator beacon) (inference may occur during communication (incl. synchronization with the network, communication of text messages and data), devices need to be turned off during search for all searching rescuers. As long as the search is in progress, use of these device on the entire avalanche should be restricted to short-lasting emergency calls in minimum distance of 25m to the closest searching rescuer. Based on new measurements, actively searching rescuers must completely turn off cellular phones as some specific, but popular models show even in “air plane mode” in distances up to 100cm interferences which trigger erratic distance / direction indications on the screen in areas where there is no real transceiver signal).


I also hadn't considered the impact of wearing my Garmin watch with Bluetooth enabled while carrying a beacon ... will have to read the article in more detail to fully understand consequence and mitigation. Fortunately, it's on my left hand, not my dominant right hand.

 

[Joel]

Many of their point are very correct. The original concern was do PLBs ( GHz in my case ) interfere with Avy location equipment. I'm not sure how likely I think it is. And maybe I should not assume this stuff is well designed.

As far as safety goes, I think it's always better to be on the side of safety. If there is an active rescue in progress, turn extra stuff off, easy.

But it isn't only that. From the referenced paper: "Metal parts, magnets and any kind of passive or active electronics potentially cause interference for a transceiver."

 

[Joel]

I just went and chatted with a guy I work with that does SAR and teaches safety classes. He is going to lend me a beacon so I can quantify some of this ( some of the issues are obvious to me, some are not ). What surprised me was that he said he has actually experienced his cell phone interfering with his beacon. He uses his phone while out, so he puts it in airplane mode.

In anycase the paper that @SBrown linked is very good and correct and is certainly the procedure to follow, this has me curious of a few things I need to check out.

 

[Monique]

What surprised me was that he said he has actually experienced his cell phone interfering with his beacon. He uses his phone while out, so he puts it in airplane mode.

Phone lines above your head and metal beams can mess with it, too. It's not just electronics

 

[Joel]

Yes, these are some the issues I understand well, it's the GHz stuff interfering I'm curious about. I can see setting your beacon on top of your cell being an issue and the paper @SBrown linked does mention distances. Being a Nerd ( work as an EE, not RF directly but I do know a bit ), I now need to look into this and satisfy my curiosity. I don't think whatever I find will change the fact that I will just turn stuff off when it is not needed, I will be repetitive here, always err an the side of safety.

Phone lines above your head and metal beams can mess with it, too. It's not just electronics