Helicopter Logging.
Wednesday 8th July 2020.
Heli-logging, or helicopter logging, is a method of logging that uses helicopters to remove cut trees from forests by lifting them on cables attached to a helicopter. Helicopter logging is often used in inaccessible areas of forests. The use of helicopters reduces the level of infrastructure required to log in a specific location, the method also helps to reduce the environmental impact of logging. It also can increase the productivity in these remote areas.
Standing Stem Harvesting, a selective harvesting method within Heli-Logging, was invented by Philip Jarman of Port Alberni, British Columbia between May and October 1997. The initial harvesting equipment used wire rope or chokers to rig the stem and a modified external hook to engage the choker and lift the stem clear of the stump. In this way, the process of harvesting, which includes climbing, measuring, cutting, rigging, and lifting was pioneered by a single pilot flying a light utility helicopter.
Heli-Logging is also known as standing stem harvesting which is based on individual tree selection. The selection process is done by engineers and surveyors. The trees are selected based on demand for specific types and grades. Before the selection process is complete the selected trees are bored to check their reliability. The selected trees are then marked, and their diameters are recorded. The diameter of the tree is measured at 1.3 meters above the ground. The sizes of the trees that are selected are controlled by two things. The minimum size is controlled by the economy while the maximum size is controlled by the capacity of the helicopter. Once the trees are selected, they are climbed, the limbs are removed, and the trees are topped. The length of the tree and the diameter at its top are then recorded. All the recorded data is then entered into a database which calculates volumes, weights, etc. The selected trees are then partially cut at the stem and supported by wooden wedges. The stem is then grappled by the helicopter and pulled until the wood breaks at the partial cut. The logged trees are then brought by helicopter to a predetermined roadside location or dropped into open water where they are collected and delivered to a sawmill.