Slide near MT/ID border

[Jethro]

did just the slope below the track slide, leaving you ok where you were? or did the slope's failure below you pull you down including the area of the track? if the former, it looks like following the track was the right decision/move.

rog

good point. The slide started at my feet, leaving me standing there while it slid away with a hissing sound.

[icelanticskier]

good point. The slide started at my feet, leaving me standing there while it slid away with a hissing sound.

good to hear. how bout that hissing sound? it's really somethin.......

rog

[panchosdad]

I ski with a lot of guides/avi instructors and have never heard any of them say "stay in my track". My take is that if that's the difference between a slope going or not, you're way too close to the edge in either case and have already made a bad decision.

In the video in this thread, if you are trying to follow the track, it's the fault of the first skier for not setting a low angle enough track that others could follow without picking up too much speed.

My .02

[icelanticskier]

I ski with a lot of guides/avi instructors and have never heard any of them say "stay in my track".

different strokes.......

My take is that if that's the difference between a slope going or not, you're way too close to the edge in either case and have already made a bad decision.

slope goes taking you with it=bad decision. slope stays put=not bad decision. slope goes below=enjoy the show

In the video in this thread, if you are trying to follow the track, it's the fault of the first skier for not setting a low angle enough track that others could follow without picking up too much speed.

it's the fault of those that follow if they don't have speed control skillz like make pizza and stuff

rog

[time2clmb]

slope stays put=not bad decision

False positive reinforcement?

[Clownshoe]

I'm with Bunion on this one. I don't think it would have made much difference if he stayed in the track or not.

If its that hair trigger, they were probably screwed regardless.

Scary stuff. Glad it turned out. Is there a rescue report or other info out there associated with this one?

[icelanticskier]

I'm with Bunion on this one. I don't think it would have made much difference if he stayed in the track or not.

we have evidence that by skier#2 going out of the track, a slide occurred. we have evidence that skier#1 went across incident free. skier#1 didn't hit the trigger point, #2 did by taking a different line. anything can happen, just seems odd to me to say that skier#2 woulda triggered either way given the scenario. especially when we don't have an either way situation. "coulda" may be more appropriate here.

rog

[AltaPowderDaze]

good to hear. how bout that hissing sound? it's really somethin.......

rog

that hissing sound is usually facets at the interface of bedsurface/weak layer that are shearing over each other. sounds creepy when you're on it.

[icelanticskier]

that hissing sound is usually facets at the interface of bedsurface/weak layer that are shearing over each other. sounds creepy when you're on it.

creepy is right. one of the largest slides i have ever intentionally set off with a ski cut (like REALLY big) produced the sound of hissing on steroids. like 2 multiple football field sheet of coarse nylon being rubbed hard against one another. the bed surface skied pretty dreamy i must say

rog

[Bunion 2020]

we have evidence that by skier#2 going out of the track, a slide occurred. we have evidence that skier#1 went across incident free. skier#1 didn't hit the trigger point, #2 did by taking a different line. anything can happen, just seems odd to me to say that skier#2 woulda triggered either way given the scenario. especially when we don't have an either way situation. "coulda" may be more appropriate here.

rog

Empirical evidence I suppose.

Talking with the owner of the permit for that area and discussing the snowpack in the area, the weak layers and the snowfall that preceded the accident are what I am going on.

Given what I have been told, an avalanche on that slope was likely.

[Clownshoe]

Rog,

I know you are a guy who likes to debate, so let me ask you this:

If you were about to ski a slope, and the only way you could do it safely was to stay directly in your track of the guy in front of you or it was going to avalanche, would you say that was a reasonable place to be? Or would you say that it was probably a very unstable slope and you probably shouldn't be there at all?

Obviously hindsight is 20-20 with respect to this particular slope releasing, but in almost 15 years of avalanche control and ski touring, I have never heard a guide or patroller or ski partner say "stay directly in my track and you'll be safe. If you go off my track you might release the whole slope".

[icelanticskier]

Empirical evidence I suppose.

Talking with the owner of the permit for that area and discussing the snowpack in the area, the weak layers and the snowfall that preceded the accident are what I am going on.

Given what I have been told, an avalanche on that slope was likely.

right on.

rog

[icelanticskier]

i wouldn't ski in someone else down tracks to begin with, so if i thought that i had to do that to stay safe, i wouldn't do it.

a traverse is different. why not all stay in the same track? makes zero sense to me not to. plus i think it's a safer, less intrusive way to go. i voice it because i like constant communication with my partners. not into willy nilly. not crossing in the same track is very willy nilly behavior, imo.

just like crossing the tracks of your touring partners when you have a whole untouched mountainside below you. just doesn't add up

rog

[Bunion 2020]

i wouldn't ski in someone else down tracks to begin with, so if i thought that i had to do that to stay safe, i wouldn't do it.

a traverse is different. why not all stay in the same track? makes zero sense to me not to. plus i think it's a safer, less intrusive way to go. i voice it because i like constant communication with my partners. not into willy nilly. not crossing in the same track is very willy nilly behavior, imo.

just like crossing the tracks of your touring partners when you have a whole untouched mountainside below you. just doesn't add up

rog

I think the best argument for staying in track is that of carrying your momentum quickly across a slope so you are exposed for less time and "in theory" as you like to say gliding smoothy across the slope.

OTOH, should you fall or travel out of track you could conceivably add stress and trigger the slope and even record it on your Go-pro camera.

Or not.

[panchosdad]

False positive reinforcement?

Exactly. Huge difference between making a good decision and making a bad one and getting away with it.

[icelanticskier]

Exactly. Huge difference between making a good decision and making a bad one and getting away with it.

the outcome is all that really matters. in the end

rog

[Yemble]

Perhaps it depends on the depth of the slab you're on? Very shallow slab is going to break the weak layer under the first skier. If it doesn't release subsequent skiers should probably stick to the same track to avoid testing another spot. Deep slab may not break down under the first skier and it would be better to spread the load instead of repeating in the same location. Snowpack suggests depth of slab. Just a thought.

tl;dr:
1. likely shallow soft slab: same track to avoid multiple collapses
2. likely deep hard slab: multiple tracks to spread the load
?

[dppaladino]

I never really post much on here, but thought I'd chime in. I'm skier #1 in the video. 2 skiers had already crossed the slope beneath where I had crossed. The skier who was caught was easily 60lbs more than the 3 other skiers. Our main mistake that day was poor time management (its hard to tell in the footage, but it was quite dark), and failure to pay attention to aspect and avoid a slope we knew had stability issues. If you guys want, I'll post the write up here that I submitted to the GNFAC.

[Yemble]

Sure, I'd like to see that. Doesn't seem to be on the website yet.