Abstract: An improved rotary actuator for torque linearization in a disk drive recording system is described. A notch is formed in the actuator frame at a point midway along one of the sidewalls of a pair of circumferential slots which define a centerpole member therebetween. These slots house the actuator coil. The notch increases the air gap between the coil and the frame at the midpoint of the data stroke. This reduces the flux density at the midpoint of the data stroke which linearizes the torque of the actuator as a function of the angular position of the coil (i.e., the coil arc). In addition, the dimension of the centerpole member which extends beyond the sweep of the coil during a data stroke is widened to decrease the air gap in these regions.