COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 146 Series Aeroplanes AD/BAe 146/38 Generator Control Unit (GCU) Replacement 1/92 TX Applicability: As specified in the requirement document. Requirement: Action in accordance with BAe 146 Mandatory Alert Service Bulletin 24-A97. Compliance: Prior to 17 November 1991. Background: BAe have advised that failure of affected GCUs to detect a single phase feeder line open circuit may lead to inaccurate instrument readings.