{"id":"F2006B03245","name":"AD/B747/65 - Fuselage - Main Frame - Tail Section 48","slug":"ad-b747-65-fuselage-main-frame-tail-section-48","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42669,"registerId":"commonwealth-F2006B03245-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/65 - Fuselage - Main Frame - Tail Section 48","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/B747/65 Fuselage - Main Frame - Tail Section 48 7/88\n\nApplicability: 747 aeroplanes line positions 001 to 200.\n\n \n\nRequirement: Action in accordance with Boeing Alert Service Bulletin 747-53A2280.\n\n \n\nNote: FAA AD 87-24-02 Amdt 39-5768 refers.\n\n \n\nCompliance: Unless already accomplished, as detailed in the Requirement Document.\n\n \n\nBackground: Two operators have reported cracks on three different splice fittings on three different aeroplanes. Analysis of one of the fittings determined that the fracture initiated due to multiple origin fatigue cracking. Three operators also reported broken tension bolts which failed due to stress corrosion.\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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD targets a specific subset of Boeing 747 aeroplanes (line positions 001–200) and requires actions set out in Boeing Alert Service Bulletin 747-53A2280. The instrument addresses reported instances of fatigue cracking and stress-corrosion bolt failures described in the Background. The text does not indicate any expansion or narrowing of scope beyond that stated applicability and the requirement to follow the service bulletin."},"complexity_factors":["Narrow applicability (only Boeing 747 line positions 001–200) reduces complexity (Applicability).","Technical remedy is delegated to an external document (Boeing Alert Service Bulletin 747-53A2280), so legal text is short but technical complexity is in the bulletin (Requirement).","Compliance outcome depends on variable inspection findings (cracks, broken bolts), which can vary aircraft-to-aircraft (Background).","Operational complexity driven by maintenance logistics, parts availability and required aircraft downtime (Requirement; Compliance).","Reference to related FAA AD creates cross-jurisdictional alignment but adds an extra document to check (Note)."],"plain_english_summary":"This AD requires operators of Boeing 747 aeroplanes at line positions 001–200 to carry out inspections and corrective actions per Boeing Alert Service Bulletin 747‑53A2280 to address reported fatigue cracking of fuselage splice fittings and stress‑corrosion failures of tension bolts.  \n\nIt matters because operators bear inspection, repair and downtime costs; the AD enforces the manufacturer’s procedures and aligns with the related FAA directive."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific structural defect in a defined aircraft population. It has not expanded beyond its original purpose of mandating repairs for fatigue cracking in Section 48 of early Boeing 747s."},"complexity_factors":["Extremely short document (under 200 words)","Only 1 defined applicability criterion (line positions 001-200)","Single external reference to Boeing Service Bulletin (no nested cross-references within the instrument itself)","No conditional logic or exceptions — straightforward 'comply with the bulletin' instruction","No interpretation section or defined terms","Background provided in plain narrative form rather than technical regulatory language"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific Boeing 747 aircraft.\n\n**What it does:**\n- Requires owners/operators of early Boeing 747s (production line numbers 001 to 200) to inspect and repair the **tail section** of the fuselage (specifically \"Section 48\" — the rearmost part of the aircraft body).\n- The work must follow instructions in **Boeing Alert Service Bulletin 747-53A2280** (an urgent technical notice from the manufacturer).\n\n**Why it matters:**\n- **Safety risk:** Cracks were found in metal fittings and bolts in the tail section of multiple aircraft. These cracks started from **metal fatigue** (repeated stress causing tiny cracks to grow) and **stress corrosion** (chemical reaction weakening metal under tension).\n- **Mandatory compliance:** Unless already fixed, operators must complete these repairs to keep their aircraft legally airworthy.\n\n**Who it affects:**\n- Airlines or operators flying early-production Boeing 747s (the first 200 built).\n- Maintenance crews responsible for structural inspections.\n\n**Key point:** This isn't optional maintenance advice — it's a legal requirement. Flying without compliance could ground the aircraft or invalidate its certificate of airworthiness."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48","history":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48/history","analysis":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48/analysis","conflicts":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48/conflicts","importantCases":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48/important-cases","documents":"/api/acts/ad-b747-65-fuselage-main-frame-tail-section-48/documents"}}