COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 767 Series Aeroplanes AD/B767/69 Amdt 1 Engine Bleed Air Crossover Duct 13/92 DM Applicability: All Boeing 767 series aircraft. Requirement: 1. Unless previously carried out, action IAW Boeing ASB 767-36A0041. Compliance: Prior to 1 April 1993 or accumulation of 7,000 flight cycles, whichever occurs later. Note: Aircraft not involved in ETOPS operations may be eligible for an extension to the compliance requirements. Background: Due to a rupture of a crossover bleed air duct loss of aircraft pressurisation, bled air to the air driven hydraulic pump, wing thermal anti-icing and also, damage to the air conditioning access panels occurred. Failure of the pressurisation may force the aircraft to descend into icing conditions with no wing anti-icing capabilities. Amendment 1 changed Compliance by replacing 31 January 1993 with 1 April 1993 and replacing the words 'occurs first' with 'occurs later'.