{"id":"F2006B03423","name":"AD/B767/69 Amdt 1 - Engine Bleed Air Crossover Duct","slug":"ad-b767-69-amdt-1-engine-bleed-air-crossover-duct","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42964,"registerId":"commonwealth-F2006B03423-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B767/69 Amdt 1 - Engine Bleed Air Crossover Duct","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBoeing 767 Series Aeroplanes\n\nAD/B767/69\n\nAmdt 1\n\n  \n\nEngine Bleed Air Crossover Duct 13/92 DM\n\nApplicability: All Boeing 767 series aircraft.\n\nRequirement: 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.\n\nNote: Aircraft not involved in ETOPS operations may be eligible for an extension to the compliance requirements.\n\nBackground: 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.\n\nAmendment 1 changed Compliance by replacing 31 January 1993 with 1 April 1993 and replacing the words ‘occurs first’ with ‘occurs later’.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a minor amendment to an existing Airworthiness Directive. The scope remains identical to the original AD — same aircraft, same defect, same required action. Amendment 1 only adjusts the compliance timing (deadline extension and logic reversal from 'first' to 'later')."},"complexity_factors":["Single, specific technical requirement (one inspection/repair action)","Only 2 operative paragraphs of substance (Applicability and Requirement)","Minimal defined terms (only standard aviation abbreviations: IAW, ASB, ETOPS)","Simple conditional logic (date OR flight cycles, whichever is later)","One explicit exception noted (ETOPS extension eligibility mentioned but not detailed)","Total length: approximately 150 words of operative text"],"plain_english_summary":"This is a **safety order for Boeing 767 aircraft** that fixes a dangerous design flaw in the engine bleed air system.\n\n**What it does:**\n- Requires airlines to inspect and repair a specific part called the \"engine bleed air crossover duct\" — a pipe that carries hot compressed air from the engines to various aircraft systems (pressurisation, anti-icing, hydraulics).\n\n**Why it matters:**\n- A ruptured duct caused a real incident where a plane lost cabin pressure, lost wing anti-icing, and lost hydraulic power. This is dangerous because the crew might have to descend through icy clouds without being able to de-ice the wings — a serious flight safety risk.\n\n**Who must comply:**\n- All Boeing 767 operators in Australia.\n\n**What changed in this amendment:**\n- Extended the deadline from **31 January 1993** to **1 April 1993**\n- Changed the logic from \"whichever occurs **first**\" to \"whichever occurs **later**\" — giving operators more time (the later of the date or flight cycles, not the earlier)\n\n**Key terms explained:**\n- **IAW** = \"in accordance with\" (following the manufacturer's instructions)\n- **ASB** = Alert Service Bulletin (an urgent manufacturer notice)\n- **ETOPS** = Extended-range Twin-engine Operational Performance Standards (long flights over oceans)"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment did not change which aircraft are affected or the substantive corrective action required. It changed only the compliance timing and the phrasing of the date/flight-cycle comparison: the calendar deadline was moved from 31 January 1993 to 1 April 1993 and the test was changed from ‘occurs first’ to ‘occurs later’ (Amendment 1). The Applicability (all Boeing 767 series aircraft) and the Requirement (action in accordance with Boeing ASB 767-36A0041) remain the same."},"complexity_factors":["Applies to all Boeing 767 series aircraft but delegates technical detail to an external Boeing service bulletin (Boeing ASB 767-36A0041) (Requirement) — reliance on an external document raises operational complexity.","Compliance is set by a calendar date or flight-cycle threshold, with the directive specifying whichever occurs later (Compliance) — this dual metric creates scheduling/calculation complexity for operators.","A note allows an extension for aircraft not involved in ETOPS operations (Note) — creates differential treatment depending on operational role.","Amendment alters calendar deadline and wording governing the date/cycle test (Amendment 1) — requires affected parties to update compliance tracking.","Technical subject-matter (bleed air crossover duct failure, pressurisation and anti-icing systems) is intrinsically specialised, so meeting the AD depends on qualified maintenance capability (Background; Requirement)."],"plain_english_summary":"This directive requires every Boeing 767 operator/owner to carry out corrective work per Boeing Service Bulletin ASB 767-36A0041 to address a bleed‑air crossover‑duct rupture risk that can cause loss of pressurisation and wing anti‑icing. Work must be done by 1 April 1993 or before 7,000 flight cycles, whichever occurs later; non‑ETOPS aircraft may qualify for a timing extension. Operators must arrange and fund the mandated work. Amendment 1 moved the deadline and clarified the date/cycle test."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct","history":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct/history","analysis":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct/analysis","conflicts":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct/conflicts","importantCases":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct/important-cases","documents":"/api/acts/ad-b767-69-amdt-1-engine-bleed-air-crossover-duct/documents"}}