Head crashes can be a problem. If the head contacts the disk surface, the
head can scrape the recording medium off the disk, destroying the data that had
been there. In older-generation disks, the head touching the surface caused the
removed medium to become airborne and to come between the other heads and
their platters, causing more crashes; a head crash could thus result in failure of
the entire disk. Current-generation disk drives use a thin film of magnetic metal
as recording medium. They are much less susceptible to failure by head crashes
than the older oxide-coated disks.