Professional versions of a zip-line are most typically used as an outdoor adventure activity. In contrast to "flying foxes" professional courses are usually operated at higher speeds covering much longer distances and sometimes at considerable heights. The users are physically attached to the cable by wearing a harness which attaches to a removable trolley. A helmet is required on almost all courses of any size.
Cables can be very high, starting at a height of over 30 feet (9 m), and traveling well over 1500 feet (457 m). All zip line cables have some degree of sag. The proper tensioning of a cable is important and allows the ability to tune the ride of a zip line.
Users of zip-lines must have means of stopping themselves. Typical mechanisms include:
- Thick purpose-built leather gloves.
- A mat or netting at the lower end of the incline.
- An arrester system comprised of springs, pulleys, counter-weights, bungee cord or other devices, which slows then stops the trolley's motion.
- Gravity stop utilizing the inherent nature of the sag in the cable. The belly of the cable is always lower than the termination point. The amount of uphill on a zip line controls the speed at which the zipist arrives at the termination point.
Costa Rica is known for their Canopy Tours where a vacationer can zip through the rainforest. The zip-lines are scattered among several platforms, some as high as 130 feet.
Zip-lines are a common way to return participants to the ground at the end of a ropes adventure course.
In past days in the Australian outback, flying foxes were occasionally used for delivering food, cigarettes or tools to people working on the other side of an obstacle such as a gully or river. Australian troops have used them to deliver food, mail and even ammunition to forward positions in several conflicts.
Zip-lines may be dangerous devices, requiring proper knowledge of ropework.
Zip-line - Wikipedia, the free encyclopedia
