Abstract: Tape cartridges are stored in guides within a plurality of open slots arrayed in a carousel which is mounted for rotation around a tape drive assembly. The cartridges are retrieved and returned with respect to their storage positions by a slider arm extendable from the drive. Cartridges are loadable and removable from the carousel via an access door. The controlling computer or controller detects presence of a jam because of a cartridge not fully nested in its storage position by actuating selected operations of the carousel so as to nudge the cartridge into its fully nested storage position. An air flow pattern is created so as to isolate the data exchanging elements of the tape drive and carousel while cooling all elements not sensitive to contamination from air flow. Light source and photocell detectors are maintained in a relatively rigid relationship so as to reliably detect tape cartridge presence in each storage slot.