Skyline logging (or skyline yarding) is a form of cable logging in which harvested logs are transported on a suspended steel cable (a cableway or "highline") from where the trees are felled to a central processing location.
The skyline's cable loop runs around a drive pulley, generally at the central delivery end, and the return pulley at the collection end; the collection-end pulley may be moved radially to other locations within the constraints of the system and may operate over large areas.
Individual logs are attached to the suspended cable by means of choker cables and carriages. A skyline yarder can pull in 5 to 10 logs at a time, using separate chokers. The pulleys are mounted on towers or cranes, other trees, ridges, or, in rare cases, helium balloons.
Satellite photograph of industrial-scale skyline logging in the Tierras Bajas project in eastern Bolivia, showing deforestation and its later associated replacement by agriculture
A funicular is a type of cable railway system that connects points along a railway track laid on a steep slope. The system is characterized by two counterbalanced carriages permanently attached to opposite ends of a haulage cable, which is looped over a pulley at the upper end of the track. The result of such a configuration is that the two carriages move synchronously: as one ascends, the other descends at an equal speed. This feature distinguishes funiculars from inclined elevators, which have a single car that is hauled uphill.
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities.
Lumberjacks are mostly North American workers in the logging industry who perform the initial harvesting and transport of trees for ultimate processing into forest products. The term usually refers to loggers in the era when trees were felled using hand tools and dragged by oxen to rivers.
Cable car most commonly refers to the following cable transportation systems:
A winch is a mechanical device that is used to pull in or let out or otherwise adjust the tension of a rope or wire rope.
A zip-line, zip line, zip-wire, flying fox, or death slide is a pulley suspended on a cable, usually made of stainless steel, mounted on a slope. It is designed to enable cargo or a person propelled by gravity to travel from the top to the bottom of the inclined cable by holding on to, or being attached to, the freely moving pulley. It has been described as essentially a Tyrolean traverse that engages gravity to assist its speed of movement. Its use is not confined to adventure sport, recreation, or tourism, although modern-day usage tends to favor those meanings.
A skidder is any type of heavy vehicle used in a logging operation for pulling cut trees out of a forest in a process called "skidding", in which the logs are transported from the cutting site to a landing. There they are loaded onto trucks, and sent to the mill. One exception is that in the early days of logging, when distances from the timberline to the mill were shorter, the landing stage was omitted altogether, and the "skidder" would have been used as the main road vehicle, in place of the trucks, railroad, or flume. Modern forms of skidders can pull trees with a cable and winch, just like the old steam donkeys, or with a hydraulic grapple either on boom or on the back of the frame (clambunk skidder).
A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and a boom hinged at its base to provide articulation, as in a stiffleg derrick. The most basic type of derrick is controlled by three or four lines connected to the top of the mast, which allow it both to move laterally and cant up and down. To lift a load, a separate line runs up and over the mast with a hook on its free end, as with a crane.
A swing yarder is a mobile piece of heavy duty forestry equipment used for pulling logs from the woods to a logging road with cables. The swing yarder is also known as a grapple yarder.
A steam donkey or donkey engine is a steam-powered winch once widely used in logging, mining, maritime, and other industrial applications.
Space Shot is a type of amusement ride manufactured by S&S - Sansei Technologies.
The Wellington Cable Car is a funicular railway in Wellington, New Zealand, between Lambton Quay, the main shopping street, and Kelburn, a suburb in the hills overlooking the central city, rising 120 m (394 ft) over a length of 612 m (2,008 ft).
A yarder is piece of logging equipment that uses a system of cables to pull or fly logs from the stump to a collection point. It generally consists of an engine, drums, and spar, but has a range of configurations and variations, such as the swing yarder.
Cable logging, also referred to as skyline logging, is a logging method primarily used on the West Coast of North America with yarder, loaders, and grapple yarders, but also in Europe.
High lead logging is a method of cable logging using a spar, yarder and loader. It was developed by Oscar Wirkkala. It is accomplished with two lines (cables) and two winches. The mainline or yarding line extends out from one winch, while a second usually lighter line called the haulback line extends out from the other winch to a 'tail block' or pulley at the tail (back) end of the logging site, and passes through the tail block and connects to the main line. Butt rigging is installed where the two lines join and the logs are hooked to the butt rigging with chokers. The procedure is to wind up the main line and the logs are pulled in, wind up the haulback and the butt rigging is pulled out for more logs or another 'turn'.
A spar tree is the tree used as the highest anchor point in a high lead cable logging setup. The spar tree is selected based on height, location and especially strength and lack of rot in order to withstand the weight and pressure required. Once a spar tree is selected, a climber would remove the tree's limbs and top the tree. Block and tackle is then affixed to the tree and cabling is run.
The Washington Winch sits in the forests of eastern Victoria near Swifts Creek and is also known as the Washington Iron Works Skidder.
A choker setter or choke setter is a logger who attaches cables to logs for retrieval by skidders or skylines. The work process involves the choker setter wrapping a special cable end (choker) around a log and then moving clear so the yarding engineer can pull the log to a central area. In clearcutting, fallers will typically cut down all the trees and limb and buck them into logs before the choke setters and others arrive to remove the logs.
A whoopie sling is an easily adjustable rope sling designed for tree pruning or tree removal. The whoopie sling works by wrapping the sling around the trunk of a tree or a heavy load bearing limb and pulling the end of the rope within the sling through a spliced choker. By adjusting the size of the eye in the rope through the choker the user is able to adjust the length of the sling constricting around the tree without needing knots. It is also becoming more common for suspending hammocks during hiking, camping, or sailing.
A choker is a close-fitting necklace, worn high on the neck.
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