Phantom avy info? 04/06/11

An observation which I just noticed in the telemetry (posted separately since the telemetry above used up the entire 20000 character limit):

The 122" snowdepth at 800 PST on April 6 (half-hour before the avalanche) is the seasonal maximum thus far at the Alpental site. Seasonal maxima were reached at several other NWAC sites in the WA Cascades at the same time, within +/- a couple of hours (Mt Baker, Stevens Pass at 4000, 4800, and 5240 ft, Paradise, etc). Given such a widespread regional maximum, the seasonal snowdepth maximum at the avalanche site (5800 ft) probably also occurred at that same time, just before the avalanche.

That is probably a very significant fact, is it not? Greater snowdepths produce less anchoring on this type of slope, as more and more of the protruding trees (of varying height) and larger rock outcrops are buried by the deepening snowpack. However, despite this obvious significance on certain types of slopes, total snowdepth appears to be largely ignored in the analysis of avalanche accidents.

It appears that the humidity differences between elevations may have had an influence.

Spring snowpack is really different from winter snowpack.

The effect of the longer days and strong diffused (especially through clouds) sunlight is underrated.

Marcus, Drew et al...I'm glad to hear you're all okay and were able to respond and care for yourselves promptly as well as keep high spirits through the day. Remarkable. Thanks also for your thoughtful reflections, very noble of you all.

Like many people here, the Phantom has always been a backup plan when conditions get sketchy.

Although I've never skied the upper sections of the Phantom I should hope this isn't true for most people.
There's a howitzer directly accross the way that we all ski by often that has fired that slope many times. In my opinion it's considerable avalanche terrain, even in the lower trees due to the slopes above and it's obvious ability to have a full slope run-out...

I wonder how much melting and seepage from the trees occured the days prior to the avalanche, creating several unstaple sliding points that allowed the crack and failure between them...

Marcus - what struck me from your story is that you guys actually stocked, carried, and knew how to use the safety gear and first aid to treat an injury. 

Amen to that. As one who has spent several hours on snow in waning light with a broken femur waiting for a sled ride, also in good company of people who knew what to do and did not lose their cool, I can't say enough about how good it was to have a puffy jacket or two, foam pads from packs, a light bivy sack, and a thermos with some hot sweet tea. Extra clothes and extra calories are essential first aid gear, for the injured and those who stay with the injured.
Really glad you guys came out of this with nothing worse. Thanks for sharing the story.

Was Roger skiing on the Fritschis?  There was mention of a Fritschi binding that broke off at its toe piece.

Hey cchapin,

The Fritchis in question were mine. Since I was in touring mode with my heel free, the leverage was huge on that toe pivot, and it just sheared the aluminum. Then the binding part came off my foot at some point I guess. That piece didn't turn up (though we didn't look that hard) even though that ski was right next to me at the tree when everything stopped.  The other ski was recovered farther down the hill, and its binding is mostly fine except the plastic toe piece is broken; not sure how that happened.

Roger was on BD Tele gear, non-releasable, which is the setup he vastly prefers and relentlessly promotes.    Unfortunately, in this case I think his bindings were a large contributing factor to his twisted knees.  The skis were eventually torn from his boots, but not before subjecting his legs to some serious torsional forces.

Dan

Regarding first aid gear, etc, we certainly could have used more. I had only half of my usual first aid/toolkit bag, which was thankfully enough when we scavenged Dan's harness and a bunch of Voile straps to make the traction splint. We would have been hard pressed to do another one with the gear we had, if I'd broken my leg too.

I usually have a SilTarp which I'd left behind -- that's never getting left behind again. We were able to keep Dan fairly warm with the one space blanket and the garbage bag liner from my pack, but Roger got the short end of the deal and was probably a little colder. Thankfully the weather wasn't too bad and we did what we could to build a snow wall around him to keep out the worst of the wind.

I also usually have some more robust painkillers, but did not at the time.

Re: bindings, I may have said already but I was on my NTN tele setup and they released from my feet without my noticing it. Not a hint of pain in my knees, thankfully, but I think I may have gone for a longer ride because my skis came off so quickly and didn't hang up on trees to slow me down.