COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Airbus Industrie A319, A320 and A321 Series Aeroplanes AD/A320/72 Frame 56 Connecting Angle 2/97 Applicability: All Airbus A320 without Airbus Industrie Modification 20941 or Airbus Industrie Service Bulletin A320-53-1011 incorporated. Requirement: Inspect the connecting angle between frame 56 and the frame support at stringer 38 in accordance with Airbus Industrie Service Bulletin A320-53-1084 Revision 1. Note: French DGAC AD 96-237-090(B) refers. Compliance: Inspect before 20,000 flights and if no cracks are detected, at intervals not exceeding 12,000 flights. If cracks are detected, reinspect at the intervals defined in Airbus Industrie Service Bulletin A320-53-1084 Revision 1. Note: Airbus Industrie Service Bulletin A320-53-1011 is terminating action for this Directive. This Airworthiness Directive becomes effective on 30 January 1997. Background: During fatigue testing, cracking of the connecting angle was discovered. This Directive inspects this connecting angle, and allows a tighter inspection regime if cracks are found.