A tape drive includes a rotary head assembly for recording and playing back a series of arcuate tracks on a moving tape where the tracks are transverse to the longitudinal axis of the tape. The tape drive includes a servo mechanism for correcting track misregistration by adjusting the position of the rotary head assembly with respect to the tape in response to servo information in the arcuate tracks. A close transducing engagement between the tape and the rotary head assembly is provided by creation of a low ambient pressure between the assembly and the tape when the assembly rotates.