Abstract: One aspect of the embodiments utilizes a disk apparatus employing a ramp loading method, which includes a ramp member having an overlapping portion with which a part of a disk having an information recording surface and a lateral side overlaps, and a groove is formed on the entire lateral side of the disk. The disk apparatus includes a protrusion formed on a portion of the overlapping portion of the ramp member that is opposed to the lateral side of the disk and the protrusion protrudes into the groove.

Abstract: A method of obtaining a limit glide height in flying a head above a recording medium being rotated. The first step is storing the medium and the head into a chamber, stepwise reducing an air pressure in the chamber, and measuring a flying height of the head and a frequency of contact of the head with the medium in each step. The second step is performing head vanish to polish away projections on the medium by means of the head under such conditions that the head at least intermittently comes into contact with the medium. The third step is reproducing the air pressure in each step in the first step, and again measuring a flying height of the head and a frequency of contact of the head with the medium in each step.