A system may include a tether, a tether gimbal assembly, a drive mechanism, and a control system. The tether may include a distal end, a proximate end, and at least one conductor. The tether gimbal assembly may be connected to the tether. The drive mechanism may be coupled to the tether gimbal assembly and may include a housing, a spindle, and a motor. The housing may be fixed to the tether gimbal assembly. The spindle may be rotatably coupled to the housing, and the tether may be coupled to the spindle and rotate in conjunction with the spindle. The motor may be coupled to the spindle and configured to rotate the spindle and the tether. And the control system may be configured to operate the drive mechanism to control twist in the tether.