Safe evacuation when working at height

Auto Descending Device

Safe Evacuation When Working At Height

The Auto Descending Device is used for emergency descent and assisted rescue. It enables the fully automatic, controlled evacuation of up to two people simultaneously.

Safe evacuation when working at height

Automatic Descent and Assisted Rescue

The Auto Descending Device is an essential safety device when working at height. In cases where regular descent via the wind turbine tower’s ladder or lift is not possible, the Auto Descending Device provides emergency descent and assisted rescue. With its bi-directional design, it enables the fully automatic, controlled evacuation of up to two people simultaneously. The dual-brake mechanism with active heat dissipation ensures reliable performance, even when descending heavy loads from great heights.



Key Features


Bi-Directional Design

The bi-directional design of the Auto Descending Device allows for the uninterrupted descent or rescue of several people. Both ends of the rope can be used for descent, enabling continuous abseiling. This allows for more people to be evacuated in a short amount of time. In addition, the intuitive design prevents human error, thus increasing safety.


Rescue & Recovery Model

With its integrated spoke handwheel, the Sosaf-2R model can be used for hoisting.


Evacuation and Rescue

The Sosaf-2R version of Auto Descending Device can be used for evacuation and rescue. The handwheel design reduces sway, ensuring smooth operation during an emergency.


Self-Cooling Double Brake

The dual-brake mechanism with active heat dissipation provides stable descent at uniform speed. Even heavy loads can be abseiled from tall towers, enabling simultaneous two-person evacuation.


High-Performance Rope

Designed for application on- and offshore, the highly robust kernmantle rope is resistant to wear, fire, saltwater spray, and high and low temperatures.


High-Strength Aluminum Alloy

The high-strength aluminum-alloy construction of the housing is lightweight and corrosion-resistant.


Ball Bearing Rope Routing

The ball bearing design of the rope routing ensures maximum durability and stability.


Optional Accessories

A flexible anchor point, edge protector, and crow bracket are available upon request. The device kit can also be configured to include additional brackets, straps, edge protectors, t-bars, and other rescue accessories.


Packaging Options

The Auto Descending Device is available in four different packaging options.

  • Moisture-proof bag: The most convenient option for technicians who carry the device to different locations.
  • Vacuum-sealed, inside a moisture-proof bag: Perfect for cases where the device is kept in a confined space.
  • Vacuum-sealed, inside a sturdy plastic box: Ideal when the device is kept inside the turbine permanently.
  • Vacuum-sealed, inside a C4H corrosion-resistant metal box: Another popular option for units that remain inside the turbine.

Customizable Rope

The rope length can be customized based on usage requirements.


Auto Descending Device

Model Sosaf-2R Sosaf-2
Descending speed ~0.9 m/s ~0.9 m/s
Rope diameter 9.6 mm 9.6 mm
Temperature range -40°C – +60°C -40°C – +60°C
Device weight 2.5 kg (excl. rope) 1.9 kg (excl. rope)
Descent load 1 person: 150 kg, max. descent height: 500 m
2 persons: 250 kg, max. descent height: 250 m
2 persons: 282 kg, max. descent height: 150 m


Model Sosaf-2R Sosaf-2
Hoisting function Yes No
Certification ANSI/ASSE, CE, CU-TR
Static rope compliant
with standard
EN 1891 Type A
Connector compliant
with standard
EN 362; anchor point: EN 795
Auto Descending Device
compliant with standard
EN 341:2011/1A
EN 1496:2006/A
ANSI/ASSE Z359.4-2013
CSA/CAN Z259.2.3-12/1/A

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