Another type of corner system uses several guns mounted on the end of the center pivot system mainline. The guns are activated in sequence from smallest to largest and back again as the machine moves past the corners. A corner span generally costs about half as much as the rest of the pivot, increasing the capital cost per acre on a square 160 acres. However, if the field is rectangular, the corner span can be extended on one or both ends, increasing the amount of irrigated acreage from 170 to 185 acres. The main difference is that all the towers move at the same speed and in the same direction.
Water is pumped into either one of the ends or into the center.
Water can be supplied to the linear either through a canal, by dragging a supply hose which is connected to a mainline, or by connecting and disconnecting from hydrants as the linear moves down the field. To gain acreage and make the transition from one side of the field to the other, some linears pivot at the end of the field. The lateral movement makes it difficult to power a linear with electricity. Usually, a diesel motor with a generator is mounted on the main drive tower and supplies the power needed to operate the irrigation system. The primary advantage of the linear is that it can irrigate rectangular fields up to a mile long and a half mile wide.