{"id":"F2005L01046","name":"AD/B747/328 - Fuselage Frame Joints at BS 1120 and 1140","slug":"ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":34607,"registerId":"commonwealth-F2005L01046-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 747 Series Aeroplanes","sectionType":"division","heading":"Boeing 747 Series Aeroplanes","content":"### Boeing 747 Series Aeroplanes\n\n| AD/B747/328 | Fuselage Frame Joints at BS 1120 and 1140 | 6/2005 |\n| ----------- | ----------------------------------------- | ------ |\n\n| Applicability: | Model 747-100B SUD, -300, -400, and -400D series aircraft; as listed in Boeing Special Attention Service Bulletin 747-53-2483 Revision 1, dated 28 August 2003, or later FAA approved revision.                                                                                             |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2005-05-08 Amdt 39-13997.                                                                                                                                                                                                    |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of 9 June 2005.                                                                                                                                                                                                     |\n|                | This Airworthiness Directive becomes effective on 9 June 2005.                                                                                                                                                                                                                              |\n| Background:    | The FAA received reports of severed tension ties at the fuselage frame joints at Body Station (BS) 1120 and 1140. Undetected fatigue cracking of the fuselage frame to tension tie joints could result in severing of the tension ties, and consequent rapid decompression of the fuselage. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n27 April 2005","sortOrder":0},{"sectionNumber":"AD/B747/328","sectionType":"part","heading":"AD/B747/328","content":"## AD/B747/328","sortOrder":1},{"sectionNumber":"Fuselage Frame Joints at BS 1120 and 114","sectionType":"part","heading":"Fuselage Frame Joints at BS 1120 and 1140","content":"## Fuselage Frame Joints at BS 1120 and 1140","sortOrder":2},{"sectionNumber":"6/2005","sectionType":"part","heading":"6/2005","content":"## 6/2005","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This instrument adopts and enforces the FAA AD's technical requirements for the listed Boeing 747 airframes and sets an Australian effective date. It does not expand obligations beyond the FAA AD or broaden the range of affected aircraft; it merely makes the FAA-prescribed actions mandatory in Australia (and specifies the Boeing service bulletin as the procedural source). There is no indication in this text that the scope has grown beyond the original safety-focused purpose described in the Background."},"complexity_factors":["Short instrument (few pages) with no internal inspection procedures — relies on external documents for technical detail","Single external cross-reference to FAA AD 2005-05-08 (Amdt 39-13997)","Reference to Boeing Special Attention Service Bulletin 747-53-2483 Revision 1 (or later FAA-approved revision)","Limited applicability to specific 747 variants (four series listed)","Practical complexity shifted to operators: they must obtain and reconcile FAA AD and Boeing SB, and implement their detailed instructions","Compliance mechanics (scheduling, parts, MRO capacity, record-keeping) create operational complexity absent from the short directive text"],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- **Requires** operators of certain Boeing 747 aeroplanes to carry out the technical actions set out in FAA Airworthiness Directive 2005-05-08 (Amdt 39-13997).  The AD is to be followed in the manner described in Boeing Special Attention Service Bulletin 747-53-2483 Revision 1 or a later FAA-approved revision.  (See: Requirement; Applicability.)\n- **Makes that requirement mandatory** in Australia from an effective date of 9 June 2005. (See: Compliance.)\n\n**Who this affects**\n\n- **Aircraft owners/operators** of Boeing 747-100B SUD, -300, -400, and -400D series aeroplanes listed in the referenced Boeing service bulletin (these are the aircraft to which the AD applies). (See: Applicability.)\n- **Maintenance organisations and MRO providers** that perform inspections and repairs on those aircraft, because they must carry out the inspections/repairs mandated by the FAA AD and service bulletin.\n- **Civil Aviation Safety Authority (CASA)** as the enforcing regulator in Australia — CASA has adopted the FAA AD as the means of ensuring Australian-registered aircraft meet the safety requirement. (Delegate signature indicates CASA action.)\n\n**Why it matters (stated purpose and technical risk)**\n\n- The FAA received reports of **severed tension ties** at fuselage frame joints at Body Stations (BS) 1120 and 1140. The stated safety hazard is that **undetected fatigue cracking** of the joints could lead to tension ties being severed, which in turn could cause **rapid decompression** of the fuselage. The AD aims to detect and correct such cracking to prevent that outcome. (See: Background.)\n\n**How it works in practice**\n\n- The AD does not itself set out inspection procedures or corrective steps in this short instrument. Instead, it makes following the FAA AD (and the Boeing service bulletin method) mandatory. That means operators must obtain the FAA AD and Boeing SB, perform the inspections and any required repairs/modifications exactly as those documents prescribe, and keep required records.\n\n**Who pays, who decides, and what behaviour changes**\n\n- **Who pays:** Operators/owners pay the direct costs: inspections, possible repairs or modification work, parts, downtime and any related operational disruption.\n- **Who decides:** FAA AD defines the technical requirement; Boeing service bulletin provides the procedures; CASA enforces the requirement for Australian-registered aircraft by issuing this AD. Operators decide scheduling and which approved maintenance organisation performs the work, subject to regulatory time limits and mandatory actions in the FAA AD.\n- **Behaviour changes:** Operators must schedule inspections/repairs on affected airframes and maintain compliance records. This may require taking aircraft out of service for inspection/repair, sourcing parts or approved repair schemes, and allocating maintenance labour.\n\n**Costs, incentives and trade-offs (mechanics, not judgment)**\n\n- **Concentrated costs:** The direct costs fall on owners/operators of the specified 747 models (a relatively small, identifiable group). Those operators face inspection/repair bills and downtime.\n- **Diffuse benefits:** The safety benefit (reduced risk of decompression) accrues broadly to passengers, crew, and the travelling public.\n- **Implementation / compliance risks:** Practical compliance depends on availability of detailed FAA AD/Boeing SB instructions, parts and approved repair facilities. Delays in parts or MRO capacity increase aircraft downtime and operational cost. If an operator fails to comply, enforcement actions can be taken by CASA.\n- **Compliance burden:** The instrument is short because it cross-references external technical documents. That reduces legislative detail but shifts complexity to operators who must obtain and follow the FAA AD and Boeing SB. Record-keeping and showing proof-of-compliance are part of the burden implied by an AD.\n\n**Net scope and effect (mechanical summary)**\n\n- The directive makes a specific safety action mandatory for a defined subset of Boeing 747s by adopting an existing FAA AD and the Boeing service bulletin as the technical method. It does not itself invent new inspection procedures or broaden the range of affected aircraft beyond the service bulletin listing.\n\n(References in the text: Applicability; Requirement; Compliance; Background.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a narrow, specific safety purpose. It addresses a single identified structural defect in specific aircraft models. There is no evidence of scope creep; the document precisely targets the fuselage frame joint issue at the two specified body stations and does not expand into unrelated maintenance requirements."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 4 defined/referenced technical terms (BS 1120, BS 1140, tension ties, fatigue cracking) with contextual explanations provided","Single compliance pathway: direct reference to external FAA AD document","No conditional logic, exceptions, or nested provisions","Simple applicability test based on aircraft model and service bulletin listing","No cross-references to other Australian legislation or regulations"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order for aircraft. It requires specific Boeing 747 models to undergo inspections and repairs to prevent a dangerous structural failure.\n\n**What it does:**\n- Orders operators of certain Boeing 747 aircraft (models -100B SUD, -300, -400, and -400D) to inspect and fix a specific structural problem\n- The problem involves **fatigue cracking** (tiny cracks that develop over time from repeated stress) at two points in the fuselage (the main body of the plane) called Body Station 1120 and 1140\n- These cracks can cause **tension ties** (metal straps that help hold the plane's frame together) to break completely\n\n**Why it matters:**\n- If the tension ties sever (break), it could cause **rapid decompression** — a sudden loss of cabin pressure that can be catastrophic\n- The FAA (American aviation regulator) found this problem first, and Australia is adopting their safety directive\n- Aircraft operators must follow the technical instructions in the referenced FAA document\n\n**Who must comply:**\n- Owners and operators of the specified Boeing 747 models listed in Boeing Service Bulletin 747-53-2483\n- Compliance became mandatory from 9 June 2005"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140","history":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140/history","analysis":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140/analysis","conflicts":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140/conflicts","importantCases":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140/important-cases","documents":"/api/acts/ad-b747-328-fuselage-frame-joints-at-bs-1120-and-1140/documents"}}