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Long Sliding Fall – Chute

March 9, 2020. AMC Hermit Lake Caretaker reported seeing a person falling end-over-end “tomahawking” the length of Chute in Tuckerman Ravine around noon. The Caretaker and Snow Ranger responding were pleased to find that the patient had no apparent injuries. The skier walked downhill to Hermit Lake and was assisted to the road by snow machine.

It was reported at the time of the fall, the skier was still climbing up somewhere near the top of Chute, wearing leather boots with micro-spikes and no ice tool. He had ski boots and skis on a back pack. The snow was still firm, barely softened by the sun.

Safe climbing of steep snow, especially hard snow requires the skilled use of stiff boots, crampons and an ice axe or two to prevent a fall from occurring. When climbing without the protection of a rope belay, preventing a fall from happening is a climber’s/skier’s primary means of safety since arresting a fall with an ice axe is difficult with, and impossible without.

Video here: https://www.instagram.com/p/B9j0hA-HtDA/?igshid=15m8w2rcfwucf

 

 

 

Sliding fall, Chute, 2019-5-12

Sliding fall, exit of Right Gully

Close call: Fall into deep waterfall hole

As winter turns rapidly to spring, a number of hazards become prevalent in the steep terrain of the Presidential Range and particularly the Headwall of Tuckerman Ravine. Waterfall holes, glide cracks or crevasses, moats around cliffs and rocks, and other deep holes open as the thick snowpack melts. A fall into these holes, which often also have significant amounts of cold flowing water which can quickly cause hypothermia, can be very difficult to escape or be rescued from. Such accidents have resulted in several fatalities in Tuckerman Ravine. A lucky skier had a very close call in this type of accident yesterday.

At 1:58 PM on Monday, April 22, a skier fell over the Tuckerman Ravine headwall and into one of several waterfall holes. Partners and bystanders quickly initiated rescue efforts and also called 911 for emergency response. Unsure of where under the snow the fallen skier was, a beacon search was initiated and could have been helpful, though this was a non-avalanche accident. At 2:18 pm, after 20 minutes out of view to the rescuers, the subject climbed out of a different hole in the snow and slid down to the rescue party below him in the slope. He had lost his skis, poles, and pack.

The subject was alert, oriented, and able to walk but in pain from several impacts during the fall. He was also cold and wet from spending most of the 20 minutes in very cold flowing water, though not submerged. The rescue party quickly changed his clothes to drier ones. They wrapped him in a sleeping bag and briefly transported him in a rescue litter obtained from the nearby Connection Cache of emergency supplies. In effort to warm the subject, the rescue party then helped the subject begin walking down the Tuckerman Ravine Trail towards Hermit Lake.

The fall line glissade track just right of center leads up to waterfall hole and accident site, with partners of the subject shown helping him walk downhill.

Meanwhile, U.S. Forest Service Snow Rangers were notified of the incident by emergency dispatchers. They travelled to Hermit Lake with urgency, aware than similar accidents have historically been fatal. Upon arriving at Hermit Lake, Snow Rangers were told by the AMC caretaker that the subject had extracted himself from the waterfall hole and was walking, with aid, down to Hermit Lake. They proceeded up the trail, meeting the rescue party at 3:20 PM. The subject, still alert and oriented but now warmer, was transported to Pinkham Notch via snowcat and released to the care of friends.

This positive outcome should be regarded as quite lucky and be taken as a warning for all who travel on steep snow slopes in spring conditions in our mountains. Had the subject, who was a strong athlete and also a climber, been unable to self-extricate himself from the waterfall hole the outcome could have been far worse. Many of these deep holes in the snow are impossible for even the strongest individual to climb out of. Extricating a person from these holes can be very dangerous for rescuers and is difficult to accomplish in a sufficiently timely manner to save a life. We know the subject would urge you to learn from this accident, giving potentially deep holes and glide cracks in the snow a wide berth and taking care to not fall above one.

The rescue initiated by partners and bystanders of the subject was a positive example we would also like you to learn from. Partners were paying attention to each other and able to quickly initiate a rescue. They had sufficient dry clothing and emergency supplies to provide proper care for the subject. Several emergency medical professionals observed the accident and immediately helped rescue efforts. Rescuers had knowledge that a litter and hypothermia wrap materials were available in nearby Connection Cache and used them. All individuals on the scene had avalanche rescue gear, as large wet slab avalanches were forecast as unlikely but not impossible that day. While a call was made for professional rescue, this group realized that they could provide timely aid to the subject and took appropriate action that could have resulted in an effective evacuation had professional rescue been delayed or unavailable. This self-reliant level of accident response is commendable. It is also the level of response that everyone travelling in the backcountry should be prepared for, every time you’re out.

Please learn from this accident to have a safer spring ski season, and see you on the hill!

Human Triggered Avalanches

On April 7, 2018, seven avalanches occured in Tuckerman Ravine. All were human triggered. This write-up discusses the weather and snowpack that lead up to these events, an objective summary of the events, and an analysis of factors that lead to at least five people being caught in one of the avalanches.

Weather

In the week leading up to April 7, 2018, our snowpack saw two rain events. The first was March 29 and 30 which delivered 0.75” of rain followed by 0.32” of rain on April 4. Both of these rain events were followed by hard freezes. On Friday, April 6, light snow showers began just after noon and continued through sunrise the following day. By the time snowfall stopped, the snowplot at Hermit Lake recorded 16cm (6.3”) of 9% snow while the summit recorded between 7 and 8” (this is an estimate based on hourly observations as the total snowfall was recorded as less due to excessive blowing snow) of snow. When snowfall began on Friday, wind at the summit was around 30mph from the south. Overnight, wind direction shifted to the west and speeds increased to 60-70mph. Weather on Saturday April 7 was clearing skies, winds diminishing to around 40mph from the west, and temperatures in the single digits on the summit and reaching into the 20sF at Hermit Lake. This weather pattern built a robust melt-freeze crust over which wind slab was built from new snow and wind April 6-7. This touchy wind slab was the avalanche problem involved in all known avalanches on April 7.

Summary of Events

During the morning of April 7, three avalanches were intentionally triggered by skiers. All three were ski cuts, two occurring in Lobster Claw (both SS-ASc-R1-D1.5-I) and one occurring on the rollover of the Little Headwall (SS-ASc-R1-D1-I). Slab depths were up to 14” and all occured on a layer of softer snow immediately above the melt-freeze crust. Of note in the Little Headwall was that the second skier through was able to trigger the “hangfire”, or slab remaining above the crown of the initial avalanche.

Examining the crown in Little Headwall. MWAC photo.

We have less definitive information on the Left Gully and Chute avalanches, which occurred shortly before and after the Hillman’s Highway avalanches, respectively. We believe that no one was caught or carried by either avalanche, both of which were triggered unintentionally. Left Gully, which was rated Moderate, produced an avalanche from a relatively thick though isolated pocket, while Chute, which was rated Considerable, produced a larger in area avalanche from a thinner slab. Both are estimated SS-ASu-R2-D1.

Unlike the other avalanches this day, the avalanches in Hillman’s Highway did involve a number of people being caught and carried. At approximately 2:00 pm, at least 40 people were climbing and skiing in Hillman’s. An individual climbing uphill from the looker’s right fork to the looker’s left fork triggered the initial avalanche as they entered the looker’s left fork. This person was not carried in the slide. The crown of this avalanche was approximately 300’ below the top of Hillman’s and ran ⅔ of the way down (SS-AFu-R2-D2-I). Of the many people in the avalanche path, at least 5 were caught and carried. USFS Snow Rangers responded to the incident and identified one injured skier who was ultimately transported to Pinkham Notch with a back injury that was not life threatening. Another individual who was also caught and carried sustained a minor injury to their hand.

Looking at the crown of the first avalanche in Hillman’s Highway. Photo by Kurt Schleicher.

The second avalanche was triggered around 2:30pm, within minutes of the initial Snow Ranger team arriving on scene. The trigger was unknown at the time, but consensus of bystanders is that this second avalanche was triggered by the same individual who triggered the first, having topped out on the ridge and beginning to ski the hang fire slab above the initial crown. This second avalanche was smaller (SS-ASu-R2-D1-I) and luckily did not capture any people or result in injuries.

Analysis

Many opportunities for learning are presented by this day which which fortunately did not involve more serious injuries. First, it’s an excellent reminder that avalanche conditions can develop during the spring months which bring crowds of backcountry skiers to Tuckerman Ravine. As with any time of year, these avalanches can widely vary in size and character. Avalanches can be of minimal concern on certain spring days, but April 7 was a day with avalanches as the primary concern for alpine travelers. On any such day, anyone venturing into avalanche terrain should bring a beacon, shovel, probe, and knowledge to use them effectively.

Carrying avalanche rescue gear is a cardinal rule for travelling in avalanche terrain. Another is travelling one at a time through areas exposed to avalanche danger. This requires recognizing avalanche terrain, which includes both terrain capable of producing an avalanche and terrain threatened by avalanches. A phrase often heard in the courtyard is, “It’s just Hillman’s”. All of Hillman’s Highway is avalanche terrain. On top of that, it’s easily the biggest gully in Tuckerman Ravine and is particularly confined. Exposing one person at a time to avalanche danger is crucial, particularly on a day like April 7. It’s likely that nobody would have been injured had this been the case.

Avalanche danger was Moderate in Hillman’s Highway on this day, which forecasts natural avalanches as unlikely and human triggered avalanches as possible. These possible human triggered avalanches can be either small and in many areas or large and in specific areas. With a number of similar avalanches in other Moderate rated areas, we consider April 7 as a small avalanches in many areas kind of day. It’s worth noting that a Moderate rated day for large avalanches in specific areas is sometimes referred to as “scary moderate”, in which you’re less likely to find signs of instability but potentially able to trigger a large avalanche. Further, remember that even small avalanches can ultimately be fatal.

The Chute was rated Considerable and produced a slightly larger in area avalanche from a thinner slab. The primary distinction between Moderate and Considerable is increased likelihood of both natural and human triggered avalanches with greater chance for larger avalanches. Other Considerable areas received little if any traffic, which we suspect is a reason that more did not produce avalanches.

All avalanche problems exhibit some degree of spatial variability. This means that the snowpack is not uniform across the terrain and avalanches can often only be triggered from specific locations. A number of people can travel on a slope, particularly one as large as Hillman’s, before someone finds this specific location and triggers an avalanche. Tracks on a slope do not mean it’s safe to ski or climb.

The Little Headwall was not rated on April 7 for lack of snow, but did have enough snow in one isolated pocket to produce an avalanche. Unrated terrain, which encompasses all of our terrain early and late in the season, can produce avalanches. The human triggered avalanche in Central Gully on Dec 1 of this season is another example. We do issue danger ratings for areas of most concern during the bulk of the season in Tuckerman and Huntington Ravines, but avalanche activity is not confined to areas forecast on a particular day.

Finally, we should touch on ski cutting. The avalanches in the Little Headwall and Lobster Claw were intentionally triggered in a controlled manner through ski cutting. This process of intentionally skiing a specific part of a slope likely to trigger an avalanche, with speed and from one safe zone to another, is an advanced practice and is only appropriate under certain conditions. A book could easily be written about the practice of ski cutting, but a simple explanation is that it is only wise when you possess a high degree of certainty about what the the ski cut will produce AND the consequences if you’re wrong. In particular, ski cutting is inappropriate when an avalanche may initiate above you. On April 7, we had the rare conditions for our terrain in which instability was limited to surface slabs and individuals were able to ski potential start zones for isolated and small pockets of wind slab. Certainty was high both in terms of anticipated result and consequences for being wrong, and avalanches above the individuals ski cutting were nearly impossible. Further, other people were not in the potential avalanche runout zones.

Brody Leven ski cutting in Lobster Claw. Photo by Lincoln Benedict.

The human-triggered avalanches on April 7 did result in injury, but everyone on the mountain lived to ski and climb another day. Luck certainly contributed to this relatively positive outcome, as did the relatively small but widespread type of Considerable and Moderate avalanche danger that day. We who like to travel in avalanche terrain rarely get such valuable lessons without more serious outcomes. Great turns can be had with minimal risk on such days, but only by choosing terrain that matches your preparedness, knowledge, certainty, and skill level.

Human-triggered avalanches, Hillman’s Highway & Gulf of Slides

On Saturday, March 10, 2018, two separate avalanche incidents were reported. During the previous 2 days, 14.5″ of snow was deposited at Hermit Lake from a nor’easter and the upslope snowfall that followed. This storm was accompanied by moderate winds that rose to the 60’s mph the afternoon before. Saturday’s advisory called for 4.5″ more snow with increasing wind shifting slightly to the NW. Avalanche danger was rated Considerable in Hillman’s Highway, along with Left Gully and the Headwall forecast zones.

Around mid-day, a party of three talked with a snow ranger on duty who advised that low visibility and continued wind loading made their plan to travel into Hillman’s Highway unwise. The party hiked to Hillman’s and entered the 75′ wide couloir onto a 15-20 degree section of the otherwise steeper runout. Soon after the party returned to the courtyard and reported that everything the snow ranger had cautioned against had played out. Two were struck by debris, knocked down, and carried downslope. Fortunately, much of the energy of the debris flow was absorbed by boulders and holes from a warm spell which reduced our snowpack substantially. When the threat of natural avalanches occurring is elevated, the risks are as well. The natural avalanche that occurred in Hillman’s Highway was much larger and would likely have been unsurvivable.

The same day a party of two skiers set a skin track near the middle gully in the Fingers area of Gulf of Slides, in sparse trees. As the terrain steepened, they began to boot along the left edge of the gully next to the trees. The snow was loose and dry with “no shearing and bonding felt okay”. The first skier had been to this area many times and stayed out of the gully as they made their way towards the rollover near the top. They had spread themselves out as they moved up the slope but paused as they reached the rollover because “something felt wrong”. In moments, the slab failed a “couple hundred feet above” the party and hit both skiers. The first skier was carried but, being on the edge of the gully, he escaped the main flow of debris while the other skier clung to a nearby bush. The skier that was carried turned his beacon to search and could not locate a signal of his partner, who was still above him. Shortly after the caught and carried skier texted for help on his cell phone, the pair made contact and eventually were able to call off the rescue response. The skier who held onto the bush lost his poles while the skier who was carried lost all his equipment though eventually recovered one ski.

Later conversations with the skiers in Gulf of Slides revealed a debate as to whether or not they triggered the slope. They considered it likely that they did not trigger the slope, but rather that it had avalanched naturally. From our perspective, the trigger is relatively unimportant in this instance. If the avalanche had not released while ascending, it is possible that they could have made it to the top and triggered the slope on the way down. In that case, much more of the slab could have been above them with more serious consequences likely. After some reflection, looking at weather data and reading the avalanche advisory, the triggering skier admitted that “overconfidence due to personal experience” in that particular area led him to ignore the obvious red flags that existed due to the snow and weather conditions that day. After the period of warm weather and ice crust which had dominated recent ski conditions, it seems likely that the scarcity heuristic was in play as well. The call of fresh powder is hard to ignore sometimes but it is important to remember that good luck can play a role in good outcomes like this one and luck is one thing no one can count on.

Water Immersion Little Headwall

A group of three was descending the streambed between the bowl and the Little Headwall. One snowboarder was unable to avoid an open hole in the snowpack. He fell into the water with his snowboard still attached to his feet. His friends were able to quickly extend a ski pole to him. Despite being pulled by the force of rushing icy water, he was able to hold his position for several minutes. Eventually, he was unable to either be pulled up or hold on, and he was dragged underneath a snow bridge. Meanwhile, other bystanders had come along. One had entered the water on the downhill side and worked at freeing the snowboarder from that end. After a couple minutes, the snowboarder was pulled free from under the snow bridge.

He was hypothermic when extricated, with a diminished level of consciousness. His friends and bystanders worked to remove him from his soaked clothes and begin the rewarming process. AMC employees arrived on scene after he had been pulled from the water. By the time Snow Rangers arrived, his level of consciousness had improved and he was able to stand up under his own power. The snowboarder was able to walk himself down to the parking lot (with borrowed dry clothes.)

Each season, we try our best to inform skiers and snowboarders of the hazards related to riding the streambed. In this case, we had stopped recommending this as a descent route three days prior. The victim and his group stated that they were aware of the hazard presented by undermined snow. In this case, the group was very unlucky in that one fell into the water, but they were also very lucky that he came out of the situation alive. Many others had skied or ridden the slope in the days before this incident, long after the conditions had deteriorated beyond a safe level. Most of these people are unaware of how close they might have been to a similar incident, so in that respect, we see a big difference between this group and all the groups that do the same thing without consequence – at least this group now fully understands the risk involved.