Avalanche Tower for manual reloading. Reliable preventive avalanche release for accessible starting zones.
In the winter season 2020/21, a total of 192 avalanche control operations were done by all 23 Mini-Avalanche Tower LS6-5.
System setup and function
Operation is being done via the Wyssen Avalanche Control Center WAC.3®
The tower is placed in the avalanche starting zone
Up to 6 charges can be loaded at 4-5 kg (9-11 lbs) of explosive each
- Reloading is being carried out manually over the ladder on the mast
- Power supply is provided by batteries supplied by solar panels
- For the deployment a charge is being dropped out of the deployment box
- During the free fall of the charge a double ignition is activated
- The charge detonates hanging on a cord above the snow cover after a time delay
- The charge height is adjustable when the charges are prepared and loaded
The deployment box is fixed on the tower. Solar panels are installed at the deployment box as well as the antenna. Inside the box sealed from the elements is the deployment mechanism, electronic control and the prepared explosive charges. Thanks to the smart concept highest reliability is guaranteed.
The explosive charge consists of two orange half-shells with pre-mounted pull activated percussion igniters with slow fuse, which are assembled with 4-5kg (9-11 lbs) of explosives. The charges are assembled by the operator on-site. We deliver the charge containers and the canvas bag for the retaining rope (6.5m / 21 ft.). Explosives and other pyrotechnical elements are purchased directly by customers from the appropriate suppliers.
Download Foundation manual:
Download Product Sheet:
Air blast with a big charge (effective range of up to 260m / 850 ft in diameter)
Simple and low priced alternative to the Wyssen Avalanche Tower LS12-5 and LS24-5
- Operation via WAC.3® just as the Wyssen Avalanche Tower LS12-5 and LS24-5
Remote control -permits rapid and weather-independent release
- No personnel in danger area
Practitioners have found that the greatest degree of success for controlled release of avalanches is achieved by a remote-controlled detonation of an effective explosive at the right time and in the right place.
From the avalanche operator’s point of view, a blasting installation must be extremely reliable and effective as well as simple to operate and maintain. The installation in the terrain must be straightforward and the interference of the installation must have minimal impact on sensitive mountain environments. Wyssen avalanche towers are ideal for fulfilling these requirements.
Smallest residual risk thanks to the largest effective range
- Blasting above the snow with bigger charges (4-5 kg / 9-11 lbs) gives the maximum effective range up to 260m in diameter
- Explosives with high detonation speeds produce N-shaped pressure waves which have been proven to cause the best release effect, particularly at a greater distance from the detonation point
- Positioning a tower on a prominent terrain feature and including a 12m (39 ft) tower instead of 10m (33ft) enables the effect to be reached in locations of pressure shadow (in couloirs, behind terrain ribs)
- Releasing smaller quantities of snow in increments, decreasing possibility for larger avalanches
- Very good stability test for assessment of the local avalanche danger
No critical or moving parts are exposed to the weather
- Solar power supply or wind generator avoids the necessity of vulnerable supply lines in the terrain
- Annual maintenance ensure maximum reliability
Reduced closure times thanks to rapid release, around the clock and in all weathers
Remote-controlled installations allow operation around the clock
Very rapid operation possible
Short closure times
Clearing away avalanche snow is usually dispensed with, since the avalanche run-outs are short due to the release of smaller portions
Low investment and operating cost in comparison with permanent protective measures (snow sheds, bridets, tunnels)
Lowest operational costs thanks to its ingenious system concept
Damage to infrastructure is avoided by the release of smaller portions
Economic benefits thanks to reduced closure times
Highest degree of safety for the operating staff
No staff in the danger area thanks to remote-controlled release
- Preparation of the charges takes place in protected areas
Foundation Footprint is only 1m2
Short construction times in the terrain simplify planning and implementation
Blasting over the ground prevents damage to the vegetation cover
Dismantling after operating life possible without any problems
All in one online platform
Wyssen Avalanche Control Center WAC.3®
The latest software generation includes new hardware for operating, monitoring and data storage of the well-proven Wyssen Avalanche Towers, detection systems and weather stations.
- Intuitive web-based operating interface
- Operable from any web-enabled device (Computer, Tablet, Notebook, Smartphone)
- Operation independent of location
- Multiple release from Avalanche Towers possible
- Monitoring of systems 24/7
- Automatic documentation and archiving of activites and system data
- Data transfer via mobile network or radio connection
In order to load and operate Wyssen systems, personnel must have attended a certified course by the company and possess a valid certificate for the artificial release of avalanches with explosives. Furthermore, it is very important that the operating staff have the corresponding training and experience for risk assessment, planning of measures, implementation of measures as well being able to assess secondary avalanches and avalanches that could be larger than expected.
Approval for storing explosives: for each tower location authorization must be requested by the customer from the responsible authorities for storing explosives in the avalanche tower deployment boxes during the period of operation.
Basic Principles of Controlled Avalanche Release
It is known from practical experience and from the theory of how avalanches arise in deep winter, that the effect of a detonation above the snow cover leads to the best results with respect to residual risk of unpredictable avalanches. The explosive devices used should give a high detonation speed and produce a large volume of gas with a high work factor. Tests with numerous experiments show that explosives with the above-mentioned properties and charging positions above the snow cover give the highest effective ranges.
The following table from the WSL Institute for Snow and Avalanche Research SLF Davos Report no. 53/1996 shows the approximate effective ranges for dry new snow of various explosive charge sizes in different positions with respect to the snow surface
In order to test and to safeguard the avalanche release zone, the whole of the potential release area must be subjected to an additional stress (e.g. by a detonation). This is necessary, because the location of the so-called „hotspots“ (super weaknesses) are not known in advance. An acceptable residual risk after blasting operations is only then reached if these „hotspots“ have been subjected to a sufficiently high additional stress and high strain rates within the snow cover with high speed of deformation (= high detonation speed).
Download “Guidelines for Artificial Release of Avalanches”:
Download “Basic principles of controlled avalanche release”:
(Table in imperial measure system)
|HEIGHT OF DETONATION POINT||CHARGE SIZE||RADIUS OF EFFECTIVE RANGE
TO PREVENT A NATURAL RELEASE
|RADIUS OF EFFECTIVE RANGE
TO PREVENT A RELEASE BY A SINGLE SKIER
|Blasting above the snow (+3 to 3.5 m)||4 to 5 kg||120 to 130 m||70 m|
|Blasting above the snow (+2 to 2.5 m)||1.5 to 2.5 kg||80 to 90 m||50 m|
|Blasting above the snow (approx. +1 m)||4 to 5 kg||80 to 90 m||50 m|
|Blasting above the snow (approx. +1 m)||1.5 to 2.5 kg||60 to 70 m||35 to 40 m|
|Surface blasting||4 to 5 kg||50 to 60 m||30 to 35 m|
|Surface blasting||4 to 5 kg||50 to 60 m||30 to 35 m|
|Blasting in snow (approx. -0.2 m)||4 to 5 kg||40 m||25 m|
|Blasting in snow (approx. -0.2 m)||1.5 to 2.5 kg||25 m||15 m|
|Blasting in snow (-0.7 m)||1.5 to 5 kg||10 m||5 to 10 m|
|Mortar 12 cm (0 m)||3 kg||40 m||–|
|RPG 8.3 cm (0 m)||0.7 kg||20 to 25 m||10 to 15 m|
|Mortar 8.1 cm (0 m)||0.6 kg||15 to 20 m||10 m|
Table from: SLF Davos Report No. 53/1996