COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 3100 (Jetstream) Series Aeroplanes AD/JETSTREAM/63 Aileron Control System Mounting Spigot Nut 5/94 Applicability: All Jetstream Series 3100 aircraft, and all Jetstream 3200 aircraft up to and including constructors number 979. Requirement: Action in accordance with Jetstream Mandatory Service Bulletin 57-JA 921140 or Service Bulletin 57-JA 921140 Revision 1. Compliance: Unless already accomplished, prior to 1 January 1995 Background: There have been reports of cracks and failures of the threaded portion of the aileron control mounting spigots. The cracking was attributed to stress corrosion.