Descending devices are essential tools used by climbers, cavers, and rescuers to safely rappel down cliffs, caves, or other vertical surfaces. There is a wide variety of descending devices available, each designed for specific types of terrain, rope systems, and user preferences. In this guide, we’ll explore the most common types of descending devices, their advantages, and how they work, including both traditional and modern devices used for single rope technique (SRT), multi-pitch climbing, and more.
1. Rack
The rack is a specialized descending device predominantly used in caving and for single rope technique (SRT). It’s an essential tool for those engaging in vertical caving or rappelling in technical terrain. The rack stands out for its ability to adjust the amount of friction applied to the rope, making it incredibly versatile and particularly useful for long, controlled rappels.
Key Features:
- Adjustable Friction: The rack allows users to regulate the friction based on the weight of the rope, which is ideal for rappels of varying lengths or with varying rope types.
- Customizable Control: This feature ensures the device remains effective regardless of rope thickness or the climber’s needs, providing precise control over the descent.
While racks are commonly used for cave rappelling or SRT, they are less frequently seen in standard climbing or mountaineering settings due to their complexity and size. However, they are invaluable for longer rappels, offering the added benefit of smoother control during the descent. To learn more about how racks work and how to rig them properly, refer to specific guides on rack descenders.
2. Figure Eight / Whale Tail
The figure eight is one of the most commonly used rappelling devices, particularly favored by climbers, canyoneers, and rescue personnel for its simplicity and effectiveness. It consists of a metal ring with a figure-eight shape, offering a straightforward way to control rope descent.
Key Features:
- Ease of Use: The figure eight is quick to set up and easy to operate, which is why it’s a favorite for beginners and sport rappellers.
- Increased Speed: The design allows for faster descents, which makes it especially popular for sport rappelling where speed is often prioritized.
However, one downside of figure eights is the wear and tear they impose on ropes. The sharp bends created by the figure-eight design can cause more friction on the rope, which could reduce the rope’s lifespan over time, especially when rappelling frequently.
Common Variations:
- Standard Figure Eights: The classic figure eight, such as the Black Diamond Figure Eight, is the most basic and commonly encountered version. It’s durable, easy to use, and reliable for most rappelling situations.
- Petzl Huit Antibrulure: This figure-eight device comes with a heat-resistant tab that prevents the user from burning their hands during long or high-friction rappels, making it a more comfortable choice for extended use.
Modified Figure Eights: Some manufacturers have introduced modified figure eights that enhance the functionality and safety of the device.
- Rescue Eight: The rescue eight, a modified version of the figure eight, features two ears at the top. These allow you to wrap the rope around the device for an automatic stop without needing to hold onto it. The extra-large ring in a rescue eight design reduces friction, making it more effective on low-angle terrain or when speed is essential.
- Petzl Pirana: This device is an advanced version that allows you to set three different braking positions. It’s often used for canyoning and rescue operations due to its versatile friction control and a built-in lock-off feature for easier handling.
3. Bobbin-Style Descenders
Bobbin-style descending devices are specialized for single rope technique (SRT) and are a preferred choice for rappelling in caving and technical rescue situations. The primary benefit of these devices is that they create gradual bends on the rope, which helps preserve the rope’s integrity over time.
Key Features:
- Gradual Friction: The bobbin-style devices apply friction over a longer section of the rope, distributing the wear and tear more evenly. This results in less rope abrasion and prolongs the life of the rope.
- SRT Specialization: Bobbin-style devices are designed for use with single ropes and are not suitable for double-rope systems.
While bobbin-style devices excel in providing controlled descents, they are not ideal for rappels involving excessive weight or very long drops, as the extra weight can cause the device to lock up. Bobbin-style descenders are best used for rappels in standard conditions where control is more important than speed.
Popular Models:
- Petzl Simple: The Petzl Simple is a straightforward, easy-to-use device that gradually applies friction along the length of the rope. Its design helps reduce rope wear and is favored for most standard rappels.
- Petzl Stop: The Petzl Stop combines the gradual friction of the Simple with a built-in camming mechanism that automatically stops the device unless manually disengaged by the user. This makes it an ideal choice for multitude rappelling scenarios, including both caving and climbing.
4. The Petzl Stop and Similar Devices
The Petzl Stop is a more advanced variation of the bobbin-style device, designed to offer greater safety and control during rappels. The camming mechanism in the Stop allows for automatic braking, which is particularly useful for longer descents or when rappelling in environments where hands-free operation is desired.
Key Features:
- Automatic Locking: The camming mechanism automatically locks the device when you release the brake, reducing the chances of uncontrolled descents.
- Versatility: While primarily designed for caving and vertical climbs, the Petzl Stop is also a viable option for traditional rappelling scenarios.
Selecting the right descending device is crucial for safety, efficiency, and maintaining the integrity of your gear. Racks provide adjustable friction, making them ideal for longer rappels and technical cave descents. Figure eights remain popular due to their simplicity, although they can wear ropes faster. Bobbin-style devices like the Petzl Simple and Petzl Stop offer gradual friction and increased rope lifespan, making them well-suited for controlled, standard rappels.
Each device has its ideal use case, depending on the terrain, rope system, and specific needs of the climber or caver. Understanding the differences and when to use each type will ensure a safe and efficient descent, allowing you to focus on the adventure ahead.