Managing the growth of trees and other vegetation around transmission lines is key to helping ensure public safety and electric system reliability. In some areas, difficult terrain and wetlands around the transmission line corridor make it very difficult to access with ground crews. The helicopter and air saw allow trimming to be performed in a few hours, while a ground-based crew might take several days to accomplish the same amount of work in difficult conditions.
The helicopters are equipped with a heavy-duty air saw with rotary blades suspended on a 90-foot vertical boom. This video shows an air saw being used to trim trees along ATC rights-of-way in Michigan’s Upper Peninsula in August 2013.