The fortifications covered the city on a 180 degree arc in two rings.
Embedded on the concrete pavement was a steel traversing mechanism once used to swing the gun in a 180 degree arc.
Appearing when fire is held down, this long beam weapon can be swung in a 360 degree arc.
These are electronically controlled and cover a 90 degree arc without moving the antenna.
Detritus's arm whirled round in a 180 degree arc with oblivion on the end of it.
The trap machine oscillates left to right within a 45 degree arc.
The entire valley below seemed to be swinging through a forty-five degree arc.
The engagement envelope is a 3 km, 45 degree arc centered on the missiles launch axis.
The arch rings are 120 degree arcs of circles.
The camera was capable of capturing an image in a 120 degree arc.
