{"id":"F2005L01746","name":"AD/B747/35 Amdt 1 - Front Spar Pressure Bulkhead Chord","slug":"ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":35828,"registerId":"commonwealth-F2005L01746-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/B747/35 Amdt 1 | Front Spar Pressure Bulkhead Chord | 8/2005 |\n| ----------------- | ---------------------------------- | ------ |\n\n| Applicability: | Model 747 series aircraft, line numbers 1 through 1307, 1309 through 1312, and 1314.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2005-10 -21 Amdt 39-14098.Note: Boeing Service Bulletins 747-53-2064 Revision 4 including Addendum, and 747-53A2471, or later FAA approved revisions, refer.                                                                                                                                                                                                                                                                                                                                                                           |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of 4 August 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n|                | This Amendment becomes effective on 4 August 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n| Background:    | Cracks were found on the fatigue test aircraft and on aircraft in-service. This Directive has been issued because Service Bulletin 747-53-2064 has been identified by the B747 Supplemental Structural Inspection Document as having flight safety implications.Amendment 1 is issued in response to a new FAA AD, which requires high frequency eddy current inspections of the body station 1000 bulkhead chord for cracks, repetitive detailed inspections of the bathtub fittings, if installed, and corrective action if necessary. The applicability is revised to include additional aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n21 June 2005","sortOrder":0},{"sectionNumber":"AD/B747/35 Amdt 1","sectionType":"part","heading":"AD/B747/35 Amdt 1","content":"## AD/B747/35 Amdt 1","sortOrder":1},{"sectionNumber":"Front Spar Pressure Bulkhead Chord","sectionType":"part","heading":"Front Spar Pressure Bulkhead Chord","content":"## Front Spar Pressure Bulkhead Chord","sortOrder":2},{"sectionNumber":"8/2005","sectionType":"part","heading":"8/2005","content":"## 8/2005","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Yes. Amendment 1 expanded the AD's applicability to include additional Boeing 747 line numbers and adopts the new FAA AD's requirements (high-frequency eddy current inspections of the body station 1000 bulkhead chord, repetitive bathtub-fitting inspections, and corrective actions). The amendment also sets a revised effective date of 4 August 2005 (Applicability; Background; Compliance)."},"complexity_factors":["Cross-references external FAA AD 2005-10-21 and Boeing Service Bulletins, making compliance dependent on those documents and their approved revisions (Requirement).","Requires specialised inspection techniques (high-frequency eddy current) and repetitive detailed inspections, which need technical capability and record-keeping (Background; Requirement).","Applicability is line-number specific and was expanded by the amendment, creating tracking complexity for fleet operators (Applicability; Background).","Corrective action is required 'if necessary', producing variable remediation scope and potential negotiation over acceptable repairs or parts (Requirement; Background).","Compliance timing and the amended effective date (4 August 2005) impose an operational scheduling burden on operators to reprogram maintenance (Compliance).","Delegation and issuance by CASA's Delegate formalises regulatory enforcement, leaving operators responsible for meeting the directive's requirements (signed directive).","Ongoing compliance risk: references to 'later FAA approved revisions' require operators to monitor for updates and adapt procedures accordingly (Requirement)."],"plain_english_summary":"This amendment to an Airworthiness Directive requires owners/operators of specified Boeing 747 line-numbered aircraft to carry out inspections and any needed repairs in line with FAA AD 2005‑10‑21 and referenced Boeing Service Bulletins. It mandates high‑frequency eddy‑current checks of the body station 1000 front spar pressure bulkhead chord and repetitive detailed inspections of bathtub fittings because cracks were found on test and in‑service aircraft. Compliance is required from 4 August 2005."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original purpose: addressing fatigue cracks in a specific structural component of Boeing 747 aircraft. While Amendment 1 expands applicability to additional aircraft line numbers (1314 and possibly others), this is a technical expansion within the same safety issue rather than scope creep. The instrument does not address unrelated systems or aircraft types."},"complexity_factors":["Short, single-purpose instrument (approximately 250 words)","Only 3 defined elements: applicability (aircraft line numbers), compliance date, and technical reference to external FAA document","Heavy reliance on external technical documents (FAA AD 2005-10-21 and Boeing Service Bulletins) rather than spelling out requirements in full","No nested conditional logic or exceptions within the instrument itself—all technical complexity is delegated to referenced documents","Simple linear structure: applicability → requirement → compliance → background"],"plain_english_summary":"This airworthiness directive requires high‑frequency eddy‑current inspections of the front spar pressure bulkhead chord at body station 1000 on affected Boeing 747s, with repeated checks of bathtub fittings and mandatory repairs for any fatigue cracks. \n\nIt covers line numbers 1–1307, 1309–1312, and 1314 because cracks were found in testing and service—risking rapid decompression—and Amendment 1 expands coverage and aligns with FAA rules, effective 4 August 2005."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord","history":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord/history","analysis":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord/analysis","conflicts":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord/conflicts","importantCases":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord/important-cases","documents":"/api/acts/ad-b747-35-amdt-1-front-spar-pressure-bulkhead-chord/documents"}}