{"id":"F2006B03099","name":"AD/B747/2 - Fuselage - Structural Modification","slug":"ad-b747-2-fuselage-structural-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42471,"registerId":"commonwealth-F2006B03099-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/2 - Fuselage - Structural Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Boeing 747 Series Aeroplanes\n\n \n\nAD/B747/2 Fuselage - Structural Modification NK\n\nApplicability: All models.\n\n \n\nDocument: FAA AD 75-15-05 (39-2262).\n\n \n\nCompliance: Before 31 December 1977.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This appears to be the original scope of the directive. Airworthiness directives are typically narrow, targeted safety fixes. There is no evidence of scope creep — it addresses a specific structural modification for a specific aircraft type with a clear deadline."},"complexity_factors":["Extremely short document (under 200 words)","No defined terms section — uses plain language only","Single compliance requirement with a fixed deadline","No nested exceptions or conditional logic","Cross-reference to external FAA document is straightforward (single reference)","Broad applicability ('All models') with no exclusions or carve-outs"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of **all Boeing 747 aircraft** to carry out specific **structural modifications to the fuselage** (the main body of the plane).\n\n**What it does:**\n- Mandates a structural fix to the Boeing 747's fuselage to address a safety defect.\n- References an American Federal Aviation Administration (FAA) directive (AD 75-15-05) for the technical details of what needs to be done.\n\n**Who it affects:**\n- Anyone operating Boeing 747 aircraft in Australia (all models are covered).\n\n**Why it matters:**\n- Airworthiness directives are legally binding. Non-compliance means the aircraft cannot fly legally in Australian airspace.\n- The deadline was **31 December 1977**, meaning this was an urgent safety fix required decades ago for the early 747 fleet.\n\n**Key point:** This is a historical directive. Modern 747s would have incorporated these changes during manufacturing, but this AD ensured existing aircraft were retrofitted by the deadline."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument's scope is explicit and limited: it applies to all Boeing 747 models and mandates a fuselage structural modification to be completed by a specified date, relying on FAA AD 75-15-05 for technical details. Nothing in the text indicates a change from that stated scope."},"complexity_factors":["Short, single-action mandate: the AD requires one modification and gives a single compliance date, reducing procedural complexity.","Dependency on an external technical document (FAA AD 75-15-05) — operators must obtain and interpret that document to know the exact technical steps, adding a layer of complexity external to this text.","Broad applicability (\"All models\") — while simple to state, it requires operators across the entire 747 fleet to assess applicability to individual airframes.","Lack of detailed implementation specifications in this instrument (no qualifications, no verification or enforcement steps included), which shifts complexity to operators and the referenced FAA AD.","Fixed compliance deadline creates scheduling and logistical complexity for operators and maintenance providers."],"plain_english_summary":"What this instrument does\n\n- This is an Australian airworthiness directive that requires a structural modification to the fuselage of Boeing 747 aeroplanes. (Header: \"SCHEDULE OF AIRWORTHINESS DIRECTIVES\" and title: \"AD/B747/2 Fuselage - Structural Modification NK\".)\n- It applies to all Boeing 747 models. (\"Applicability: All models.\")\n- It requires operators to carry out the modification before 31 December 1977. (\"Compliance: Before 31 December 1977.\")\n- The directive points aircraft operators to FAA AD 75-15-05 (39-2262) for the technical instructions. (\"Document: FAA AD 75-15-05 (39-2262).\")\n\nWho decides and who pays\n\n- The Civil Aviation Safety Authority (CASA) of the Commonwealth of Australia issued this directive under the airworthiness-directive schedule (header: \"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - ... CIVIL AVIATION SAFETY AUTHORITY\"). CASA sets the requirement and compliance date.\n- Aircraft owners and operators are the parties who must implement the modification and therefore bear the direct costs (the compliance requirement and deadline are directed at operators; see \"Applicability\" and \"Compliance\").\n\nWhy it matters (stated purpose and how it operates mechanically)\n\n- As an airworthiness directive, the instrument's functional purpose is to require a specified modification to address an airworthiness concern for Boeing 747 fuselages. The directive does not reproduce the technical steps; it instead references the FAA airworthiness directive that contains the technical instructions (\"Document: FAA AD 75-15-05\").\n- Mechanically, the instrument operates by: (1) identifying the affected fleet (all 747 models), (2) mandating completion of the specified modification by a fixed date, and (3) directing operators to follow the external FAA AD for the detailed work instructions.\n\nPractical effects, incentives, trade-offs and implementation points to note\n\n- Cost and who pays: Owners/operators must fund the modification work and absorb associated downtime. The instrument itself does not set funding arrangements or subsidies (see \"Compliance\").\n- Reliance on an external technical document: The directive delegates technical detail to FAA AD 75-15-05 (\"Document\"), so operators must obtain and follow that FAA document to know what work is required. That creates a dependency on a non‑Australian source for the detailed specification.\n- Timing and scheduling pressure: The hard compliance deadline (\"Before 31 December 1977\") imposes a fixed window for completion. That creates scheduling and capacity pressure for maintenance providers and may require aircraft to be taken out of service to complete the modification.\n- Compliance burden and discretion: The directive mandates action but does not specify who may perform the modification or any verification/inspection regime in this text. Operators must interpret the FAA AD and CASA's AD together to determine qualified personnel, documentation and proof of compliance.\n- Effects on market actors: The requirement creates demand for maintenance work that qualified providers can supply; it may concentrate business with firms qualified to do the specific structural modification. The instrument itself does not prescribe supplier selection rules or competitive processes.\n- Opportunity costs and substitution: Aircraft that are held out of service for the modification incur opportunity costs (lost revenue) until work is complete. Operators may choose timing and which facility to use, subject to whatever qualifications the FAA AD requires.\n- Implementation risk: Because the directive refers to an external FAA AD for technical detail, any ambiguity or differences in interpretation between the CASA notification and the FAA document could create compliance uncertainty. The AD text here does not include enforcement measures, so further CASA guidance or audit procedures (not present in this text) would determine how non-compliance is handled.\n\nConcrete, source-cited statements\n\n- Applies to all Boeing 747 models. (\"Applicability: All models.\")\n- Requires completion of the listed fuselage structural modification by 31 December 1977. (\"Compliance: Before 31 December 1977.\")\n- Technical instructions are contained in FAA AD 75-15-05 (39-2262), which operators must use to carry out the work. (\"Document: FAA AD 75-15-05 (39-2262).\")\n- The directive is issued under the Commonwealth airworthiness-directive schedule administered by the Civil Aviation Safety Authority. (Header: \"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 ... CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES.\")"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-2-fuselage-structural-modification","history":"/api/acts/ad-b747-2-fuselage-structural-modification/history","analysis":"/api/acts/ad-b747-2-fuselage-structural-modification/analysis","conflicts":"/api/acts/ad-b747-2-fuselage-structural-modification/conflicts","importantCases":"/api/acts/ad-b747-2-fuselage-structural-modification/important-cases","documents":"/api/acts/ad-b747-2-fuselage-structural-modification/documents"}}