Abstract: An improved recording cartridge contains a flexible magnetic recording disc. The lower interior major surface of the cartridge provides a smoothing plane for the flexible magnetic recording disc positioned inside the cartridge to allow the disc to rise slightly above the lower interior major surface on a cushion of air while the disc is in rotation. To enhance the stability of the disc and to make the disc conform more readily to the shape of the magnetic head transducer, the lower interior major surface includes a raised portion thereon. This raised portion gives the disc added rigidity and prevents it from flying away from the head during head penetrations and horizontal movement. The remainder of the smoothing plane surface is relatively flat, thereby permitting a thin cartridge configuration to be used.