COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Piper PA-24 (Comanche) Series Aeroplanes AD/PA-24/43 Wing Main Spar Lower Cap - Inspection 9/83 Applicability: All model PA-24-400 with S/Nos. 26-2 and subsequent. All model PA-24-180, PA- 24-250 and PA-24-260 with S/Nos. 24-1 and subsequent. Document: Piper Service Bulletin No. 751. Compliance: Within 100 hours time in service after 30th September 1983. Background: The manufacturer reports cases of chafing of the wing main spar lower cap where the spar enters the fuselage.