Rotary head data storage and retrieval system and method with tape medium having transverse primary data tracks and longitudinal secondary data track

A data storage and retrieval system includes a head carriage unit having multiple heads disposed at a working surface and a tape drive unit configured to move the tape past the working surface of the head carriage unit in a direction substantially parallel to a tape length. The heads are configured to write primary data tracks to or read primary data tracks from the tape as the head carriage unit rotates and the tape moves past the working surface, the primary data tracks having an accurate shape and extending substantially along a tape width. The heads are also configured to write at least one secondary data track to or read at least one secondary data track from the tape as the head carriage unit rotates and the tape moves past the working surface, the at least one secondary data track extending substantially along the tape length.