Patent ID: 8861123

Claim:
A disk drive comprising: a first disk surface comprising servo information; a first head actuated over the first disk surface; a second disk surface; a second head actuated over the second disk surface; a voice coil motor (VCM) operable to actuate the first and second heads radially over the respective disk surfaces; and control circuitry operable to: rotate the first disk surface and the second disk surface; read the servo information from the first disk surface using the first head to generate a read signal; and process the read signal to generate a control signal applied to the VCM to move the second head radially over the second disk surface while applying an erase signal to the second head in order to erase at least part of the second disk surface, wherein: the second head comprises a write element that spans a radial segment of the second disk surface; the control circuitry is operable to move the second head radially over the second disk surface such that the write element moves less than the radial segment over a single revolution of the second disk surface; and the radial segment changes toward a middle diameter of the second disk surface.