Text in force at 23-63: from 23-20, effective 1 Sep 1977.
[If a flight director system is installed, means must be provided to indicate to the flight crew its current mode of operation. Selector switch position is not acceptable as a means of indication.] Notice of Airworthiness Review No. 2; Notice No. 75-10; Issued on 02/27/75. Notice of Airworthiness Review No. 5;
42 FR 36969 · Source