Avalanche control by helicopter – preemptive action
Despite there being less snow in lots of places at the moment than in other years, the longer-term avalanche risk is high. This is due to the structure of the snow cover, which is unstable, brittle, and made up of layers that have not bonded together well. The result of this is that we’ve seen a surprising number of spontaneous avalanches this winter, making it all the more important to carry out controlled, artificial triggering of avalanches. This is a job where precision, experience and teamwork are crucial.
In Switzerland, artificial avalanche triggering is an important way to protect traffic routes, residential areas and ski resorts. The aim of these interventions is not to create a spectacle, but to reduce risks – possible starting zones are temporarily secured, and snow buildup on avalanche pathways is reduced in a controlled manner. At the same time, this approach helps to avoid large spontaneous avalanches and huge inconvenience down below. In short, avalanches are triggered in a targeted manner before they can cause uncontrolled damage. The use of helicopters is vital when it comes to avalanche blasting.
Avalanche risk mitigation
Early in the morning, a radio message breaks the silence on the base. It snowed overnight – not a lot – but a quick glance at the slopes is enough to see that the snow cover is unsafe. In Valais, this has been the situation for weeks now. Avalanche danger level 3 over an extended period, despite relatively small amounts of snow. This winter has seen plenty of avalanches occurring spontaneously, without warning. And this is exactly why the safety efforts start well before anything like that can happen. There are a number of ways to trigger an avalanche artificially.
Safety on the slopes
When it’s time for ski resorts to secure their slopes, Air Zermatt is called out to a series of locations in Valais. Safety officers board the helicopter together with the crew, and the route is discussed. From below, a flight like this can look like a single calm arc over the slope – but in the cockpit and at the open door, the work is highly focused. Where to place the explosive charge? What about the wind? How will the snow cover behave on exactly this ridge, exactly this edge?
The charge is set down by the task specialist according to instructions from the resort’s safety expert. The resulting shock wave is intended to do what the mountain would otherwise do itself at some point, but in a controlled approach and supervised by specialists. A muffled bang, and the slope starts to move. Snow breaks up, slides off, collects lower down. Nothing unexpected, no risk. A well-planned process.
Keeping traffic routes open
The same preventive measures are taken to make sure traffic routes can stay open after heavy snowfall. It’s more than just an inconvenience if roads or railroad lines have to be closed for safety reasons. The valleys are cut off, people can’t get to work, and supply chains are interrupted. Avalanche blasting from a helicopter can help to reopen traffic routes. Again, this is a process involving a safety expert in the helicopter showing exactly where each charge should be placed.
The goal is always the same – to reduce the risk on dangerous parts of the slope in a controlled manner so the roads can be reopened as quickly as possible. Again, not for the spectacle, but for the vital purpose of allowing the people in the valley to go about their everyday lives.
Permanent installations impossible without a helicopter
In addition to these helicopter missions from the air, permanently installed systems for artificially triggering avalanches, like the Wyssen detonator mast, are also used. The mast is several meters high, and fitted with a magazine with several explosive charges that can be detonated remotely above the snow cover. But even this solution can only work with air support, with a helicopter being needed to replace the empty magazines. The magazine is positioned on the mast with the utmost precision – just the job for Air Zermatt’s helicopter pilots.
Teamwork for the common good
Ski slope, main road, or railroad line – avalanche blasting is always a team effort. The emergency services, ski resorts, authorities, and the Air Zermatt crew work together in in unison, with the shared goal of minimizing risks, protecting infrastructure, and maintaining mobility.
This collaboration becomes especially important in a winter when the snow cover is unstable. These interventions might often be invisible to the public, but their impact can’t be overstated when it comes to ensuring safe slopes, open traffic routes and bringing a certain reliability to an alpine environment that is constantly in flux.
