A seek control device, such as a CPU, moves a head to a particular track on a recording surface of a disk before a head unload operation. A speed feedback control device, such as the CPU, detects the movement speed of the head at predetermined sampling intervals and then performs speed feedback control on the basis of the detected speed. The speed feedback control is performed a predetermined number of times. By integrating the speed detected at the sampling intervals, an estimation device, such as the CPU, estimates the distance that the head has moved while the speed feedback control is performed the predetermined number of times. A head unload operation determining device, which may also be the CPU, determines whether the head unload operation has been correctly completed on the basis of the estimated head movement distance.