14 CFR § 27.1329 - Automatic pilot system.
(a) Each automatic pilot system must be designed so that the automatic pilot can -
(1) Be sufficiently overpowered by one pilot to allow control of the rotorcraft; and
(2) Be readily and positively disengaged by each pilot to prevent it from interfering with control of the rotorcraft.
(b) Unless there is automatic synchronization, each system must have a means to readily indicate to the pilot the alignment of the actuating device in relation to the control system it operates.
(c) Each manually operated control for the system's operation must be readily accessible to the pilots.
(d) The system must be designed and adjusted so that, within the range of adjustment available to the pilot, it cannot produce hazardous loads on the rotorcraft or create hazardous deviations in the flight path under any flight condition appropriate to its use, either during normal operation or in the event of a malfunction, assuming that corrective action begins within a reasonable period of time.
(e) If the automatic pilot integrates signals from auxiliary controls or furnishes signals for operation of other equipment, there must be positive interlocks and sequencing of engagement to prevent improper operation.
(f) If the automatic pilot system can be coupled to airborne navigation equipment, means must be provided to indicate to the pilots the current mode of operation. Selector switch position is not acceptable as a means of indication.
The following state regulations pages link to this page.