Fatality on Cameron Pass

[timmaio]

Near Nokhu crags, two caught, one fatality:

Avalanche Fatality near Cameron Pass
One backcountry tourer was killed and another seriously injured in an avalanche on 3/2, southwest of Cameron Pass. This was the 4th avalanche fatality in Colorado this season, and the 4th avalanche fatality in the US in March. On 3/1, there were fatalities in Wyoming, Utah, and New Hampshire. We will update the preliminary reports as we learn more. Our thoughts and condolences are with the victims' families and friends.

https://avalanche.state.co.us/acc/ac...=497&accfm=rep

[timmaio]

Holy crap, the guy that survived was buried for 3 hours.

[capulin overdrive]

What about the dog?

[Tech Tonics]

Holy crap, the guy that survived was buried for 3 hours.

where did you hear this?

[capulin overdrive]

Somebody has better links on the front page here.

Dog's now getting blamed for triggering the avi.

[timmaio]

where did you hear this?

http://www.coloradoan.com/article/20...lled-avalanche

[Tech Tonics]

thanks^^^

three hours wearing an avalung. holy shit.

and the dog triggered it. dogs penetrating deeper layers maybe?

sad story. huge slide.

[totaliboard]

i can see how a dog would sink further down.. nothing to displace their weight.

[ShadyNasty]

thanks^^^

three hours wearing an avalung. holy shit.

and the dog triggered it. dogs penetrating deeper layers maybe?

sad story. huge slide.

He must have managed to keep it completely clear of snow/ice during the slide. I wonder if he was skiing with it in or if he managed to get a hold of it during the slide?

Also did the dog live?

Sad story, RIP to the victim and vibes for their family

[timmaio]

He must have managed to keep it completely clear of snow/ice during the slide. I wonder if he was skiing with it in or if he managed to get a hold of it during the slide?

Also did the dog live?

Sad story, RIP to the victim and vibes for their family

He didn't actually have the avalung in his mouth is what I heard. It was just that he had about a 4" air pocket and managed to not get an ice mask(or a delayed ice mask) and went into hypothermia(a good thing in this case)

[Hacksaw]

He didn't actually have the avalung in his mouth is what I heard. It was just that he had about a 4" air pocket and managed to not get an ice mask(or a delayed ice mask) and went into hypothermia(a good thing in this case)

That's correct....

[AK47bp]

Anyone know the avy danger level at the time of the slide?

[bean]

Anyone know the avy danger level at the time of the slide?

987654321

[Jonathan S.]

The final two words in the official account are intended to apply to the medical survival:
https://avalanche.state.co.us/acc/ac...nv&view=public
... but they also aptly describe the botched beacon search.

[LeeLau]

"Both rescue groups reported difficulty in isolating the two different beacon signals. Although both victims were buried in the same portion of the debris, they were more than 10 meters apart (rough definition of close proximity for a multiple beacon search). The two victims were both wearing older, single-antenna beacons and the searchers were using newer, two and three antenna beacons. The difference in pulse rate of the two transmitting beacons may have contributed to the difficulty of the search."

[neufox47]

The final two words in the official account are intended to apply to the medical survival:
https://avalanche.state.co.us/acc/ac...nv&view=public
... but they also aptly describe the botched beacon search.

So even the pros forgot / failed to turn off victim 1's beacon? Crazy. Great read. Every backcountry traveler should read this write up. More and more I think I never want to ski a north facing slope in CO that isn't avy controlled.

[Hugh Conway]

"Both rescue groups reported difficulty in isolating the two different beacon signals. Although both victims were buried in the same portion of the debris, they were more than 10 meters apart (rough definition of close proximity for a multiple beacon search). The two victims were both wearing older, single-antenna beacons and the searchers were using newer, two and three antenna beacons. The difference in pulse rate of the two transmitting beacons may have contributed to the difficulty of the search."

Don't all beacons transmit from a single antenna? I'm guessing they are intimating it was beat frequency problems? But that's possible with any beacon under the specs.

[LeeLau]

I don't quite get what the CAIC report is getting at. Maybe the older beacons had frequency drift? ie the "The difference in pulse rate of the two transmitting beacons " excerpt.

[TBS]

Don't all beacons transmit from a single antenna? I'm guessing they are intimating it was beat frequency problems? But that's possible with any beacon under the specs.

Yup, they all transmit on one antenna - the multiple antennas come into play when searching.
I don't get the part about different pulse rates either, unless they are trying to really obliquely say that the survivor's beacon had major drift. You'd think someone in the group of four would have noticed when they did their test at the trailhead...

[mattyj]

This is wild conjecture . . .

I don't use a beacon with a mark/flag feature, but in training on multiple burials with people that do, I've run into occasional compatibility issues. They seem more willing to "lose" some signals than others, and start guiding you back towards the beacon you just flagged. A friend has one that will suddenly start reporting 3 burials once it gets within 10 feet or so of my Ortovox M2.

When teaching beacon searches, I like to start with an analog receiver, work up to a 2-antenna beacon like the Tracker and finally have people play with their 3-antenna multi-burial-capable beacons. Recently, I did this with an old analog beacon as the target and was very surprised at how fast the beacon rate was. Like 2-3x faster than normal; if you had two of them going there would barely be any silent time and I can see how it would be hard - as a human - to differentiate between them.

All of which is to say that while all beacons should work with all other beacons, some of them seem more compatible than others. I don't know what all the contributing factors are, but I wouldn't be surprised if beacon rates play a role, at least at the extremes - and they do seem to have changed over the years.

[neck beard]

Were they talking about signal overlap?

Even if so, it doesn't last for 10's of minutes on end. But when the signals do line up temporarily, a searcher can only sometimes 'see' one signal.

[Jonathan S.]

So even the pros forgot / failed to turn off victim 1's beacon?

Sounds like it from the report, but then again, they might not have needed to: even though they described the search as “tricky” they might still have successfully flagged/marked/masked the partially excavated deceased victim, then decided to move onto the second victim w/o turning off the first found victim.
(Yes, that is entirely conjecture, but either way, it’s unclear from the report.)

Don't all beacons transmit from a single antenna? I'm guessing they are intimating it was beat frequency problems? But that's possible with any beacon under the specs.

Re transmission, just wanted to take this opportunity to add that the Ortovox Zoom, 3+, and S1+ can *choose* from two different transmission antennas (so as to avoid transmitting into the vertical plane), but yes, they always transmit from only one antenna at a time.

What the report seems to be intimating is exactly backwards: the “difference in pulse rate of the two transmitting beacons” would help the search, not hinder it.

I don't quite get what the CAIC report is getting at. Maybe the older beacons had frequency drift? ie the "The difference in pulse rate of the two transmitting beacons " excerpt.

I’m also puzzled. The only excuse for the botched companion rescue is that the surviving victim’s old beacon might have drifted out of spec. Yes, the officers' beacons were able to pick up the signal, but different models vary widely in how well they can locate an out-of-spec signal.

I don't get the part about different pulse rates either, unless they are trying to really obliquely say that the survivor's beacon had major drift. You'd think someone in the group of four would have noticed when they did their test at the trailhead...

Not necessarily. Some models do have a frequency tester.
But if not (warning, conjecture coming up!), they could have done the second and final part of the beacon check by having three of them pass through the trailhead to be checked for transmission by the soon-to-be deceased partner, who might have had a beacon that is more tolerant of drift.
Or (more conjecture!), all the checking might have been conducted at a very close range.
Example: I grabbed a whole bunch of old F1 beacons for use as targets at a large avy course. I tested their frequency before practice burials. Back in the hotel room later that evening, I realized I had even more F1 units forgotten in my pack. I tested one of them. Whoah! I “buried” it in one corner of my hotel room, then tried to “search” for it. I couldn’t find the signal until I was about a meter away. However, had I conducted a trailhead check at only that distance, and without a frequency tester beacon, I would have concluded that it was okay.

When teaching beacon searches, I like to start with an analog receiver, work up to a 2-antenna beacon like the Tracker and finally have people play with their 3-antenna multi-burial-capable beacons. Recently, I did this with an old analog beacon as the target and was very surprised at how fast the beacon rate was. Like 2-3x faster than normal; if you had two of them going there would barely be any silent time and I can see how it would be hard - as a human - to differentiate between them.

All of which is to say that while all beacons should work with all other beacons, some of them seem more compatible than others. I don't know what all the contributing factors are, but I wouldn't be surprised if beacon rates play a role, at least at the extremes - and they do seem to have changed over the years.

I like your approach for teaching! I demonstrate something similar at the starts of my rescue demos. Very important for students to realize that all the victim’s beacon is doing is going Beep and an old analog beacon (or some modern models with analog mode) is very helpful for allowing you to listen in directly on the signal.

However, just some clarifications:



In general, a shorter Period helps with digital processing, since the information can be refreshed more frequently.
A longer On time creates problems for signal separation. The F1 was deliberately designed with a longer On time so that it could be heard more easily with the acoustical-dependent beacons of its day. But it’s so long, and it can vary a bit throughout its length, that signal separation beacons can sometimes count it as two separate signals.
Furthermore, the F1's Off isn’t quite entirely off:
http://beaconreviews.com/transceivers/CCP.asp

Were they talking about signal overlap?

Even if so, it doesn't last for 10's of minutes on end. But when the signals do line up temporarily, a searcher can only sometimes 'see' one signal.

Exactly! If this was a typical botched search, then might just been bad luck with signal overlap.
But the report says, “they spent approximately an hour conducting a beacon and visual search for Skier 1 without success [...]” They even could have gone back to where they had good cell reception and watched Youtube video tutorials on how to conduct a beacon search, then returned with better skills.

[Jonathan S.]

So immediately after writing all that, I received some additional information.

The two buried beacons are indeed models that are known to have transmission characteristics toward opposite ends of the spec. So the report said when it meant to say on that part.

The various searching beacons were a mix of 2 & 3 antennas (as the report also says clearly), but not marking/masking/flagging models. (In case you're trying to guess the search model(s) from that description, that still leaves open the possibility for NINE different models.)

I have a little bit more information, and I might be able to squeeze out more from my source when I corner him later this month, but I still find the entire thing absolutely baffling, and suspect it always will be (plus any more info I get will probably be confidential).
Then the irony that one of the most botched beacon searches ever leads to one of the longest backcountry burial survivals ever. Let's all wish the survivor a full recovery, and hope the searchers are motivated to improve their searching (or just stay in bounds...).

[neufox47]

Wonder if one of the rescuers in the first party had their beacon on transmit? That would explain it better than the signal issues. Impossible to tell though.

[bodywhomper]

Let's all wish the survivor a full recovery

here's the follow-up denver post article including interview info with the survivor.
http://www.denverpost.com/news/ci_22...during-3-hours

not that this necessarily is 'the answer', but don't the M1 and M2 have relatively fast 'pulse rates'? I remember at least one of them does.