Patent ID: 7271975

Claim:
A magnetic disk apparatus comprising: a magnetic disk in which plural annular tracks including plural sectors, each comprising servo areas for recording servo data and user areas for recording user data, are concentrically formed; a magnetic head slider disposed with a magnetic head that flies over the rotating magnetic disk and records data to, or plays back data from, the magnetic disk; and a control device that controls the operation of the apparatus, wherein slider flying height data that vary inside the same track are recorded in the tracks of the magnetic disk, and wherein the control device controls the slider flying height on the basis of the slider flying height data recorded in the tracks so as to prevent collision of the magnetic head slider with respect to the magnetic disk, and wherein: the slider flying height data of each sector inside each track of the magnetic disk are recorded in a sector preceding that sector, and the control device controls the operation of the apparatus on the basis of the slider flying height data recorded in each sector so that the flying height of that sector becomes substantially the same as the flying height of the other sectors.