A magnetic disk drive comprises a recording medium, a slider, and an alignment device for aligning the slider with respect to the medium. No film made of liquid lubricant is disposed on the surface of the medium. The slider incorporates: a slider main body including a thin-film magnetic head element disposed near a medium facing surface; and a protection film made of a tetrahedral amorphous carbon film for protecting the medium facing surface. The alignment device makes the slider retreat from the surface of the medium when the medium is stopped, and makes the slider face toward the surface of the medium when the medium is rotated. The magnetic disk drive further comprises a distance control device for controlling the distance between the medium and the thin-film magnetic head element.