{"id":"F2008L00156","name":"AD/B737/313 - Circumferential Butt Splices and Bonded Doublers","slug":"ad-b737-313-circumferential-butt-splices-and-bonded-doublers","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72311,"registerId":"commonwealth-F2008L00156-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/313 | Circumferential Butt Splicesand Bonded Doublers | 2/2008 |\n| ----------- | ----------------------------------------------- | ------ |\n\n| Applicability: | Model 737 series airplanes listed in Boeing Service Bulletin 737-53-1076, Revision 4, dated 26 September 1991; certificated in any category.                                                                                                                                                                  |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Carry out inspections and, if required, repairs contained in the technical requirements of FAA AD 92-25-09.Note: FAA AD 92-25-09 refers.                                                                                                                                                                      |\n| Compliance:    | Carry out inspection and, if required, repairs at intervals specified in the technical requirements of FAA AD 92-25-09 except with a revised effective date of14 February 2008. Where FAA AD 92-25-09 specifies a compliance time relative to 28 May 1991, revise this date to the effective date of this AD. |\n|                | This Airworthiness Directive becomes effective on 14 February 2008.                                                                                                                                                                                                                                           |\n| Background:    | Operators have reported occurrences of delamination or corrosion of bonded skin panels. This AD requires inspections and repairs to prevent cabin pressurisation difficulties or possible rapid decompression.                                                                                                |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n4 January 2008","sortOrder":0},{"sectionNumber":"AD/B737/313","sectionType":"part","heading":"AD/B737/313","content":"## AD/B737/313","sortOrder":1},{"sectionNumber":"Circumferential Butt Splicesand Bonded D","sectionType":"part","heading":"Circumferential Butt Splicesand Bonded Doublers","content":"## Circumferential Butt Splices  \nand Bonded Doublers","sortOrder":2},{"sectionNumber":"2/2008","sectionType":"part","heading":"2/2008","content":"## 2/2008","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":3,"scope_assessment":{"changed":false,"description":"This AD adopts the technical requirements and intervals of FAA AD 92-25-09 for the same set of Boeing 737 airplanes listed in Boeing Service Bulletin 737-53-1076 Rev 4, with the only substantive change being the substitution of the compliance reference date 28 May 1991 for this AD’s effective date of 14 February 2008. It does not expand applicability or add new types of obligations beyond inspections and repairs."},"complexity_factors":["Cross-reference to an external instrument (FAA AD 92-25-09) for technical requirements and intervals, requiring operators to consult another document.","Specific applicability limited to Boeing Service Bulletin 737-53-1076 Revision 4 — requires operators to confirm fleet applicability before acting.","Single, discrete procedural requirement (inspect and repair) with a narrow safety focus, reducing legal complexity.","A single, clear modification to compliance timing: replace dates referenced to 28 May 1991 with the AD effective date (14 Feb 2008).","Operational/compliance burden falls on operators: labour, parts, and aircraft downtime; enforcement by CASA creates regulatory risk if ignored.","No broad discretionary powers or novel certification obligations in the AD text itself — technical detail is delegated to the FAA AD."],"plain_english_summary":"This Airworthiness Directive requires operators of Boeing 737 series aeroplanes listed in Boeing Service Bulletin 737‑53‑1076 Revision 4 to inspect for delamination or corrosion of bonded skin panels and to carry out any repairs specified in the technical requirements of FAA AD 92‑25‑09. It adopts the FAA compliance intervals but replaces any deadlines tied to 28 May 1991 with this AD’s effective date of 14 February 2008. Operators pay for and schedule the inspections/repairs; CASA enforces compliance to reduce the risk of pressurisation failure."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing specific structural integrity issues on Boeing 737 fuselage joints. It has not expanded beyond its initial safety purpose of preventing pressurisation failures due to delamination and corrosion in bonded skin panels."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 1 defined term implicitly referenced (FAA AD 92-25-09, which is incorporated by reference rather than defined in the text)","No nested conditional logic — simple 'inspect and repair if required' structure","Single cross-reference to external technical document (FAA AD 92-25-09)","Minimal exceptions: only date adjustments for compliance timing","Straightforward applicability criteria referencing a single Boeing service bulletin"],"plain_english_summary":"This AD orders operators of certain Boeing 737s to inspect circumferential butt splices and bonded doublers for delamination and corrosion, and to repair any damage. The defects can compromise cabin pressure and risk rapid decompression. It requires following the FAA’s AD procedures (with updated dates) and applies to airplanes covered by the referenced Boeing service bulletin — a preventive safety step for all affected 737 operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers","history":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers/history","analysis":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers/analysis","conflicts":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers/conflicts","importantCases":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers/important-cases","documents":"/api/acts/ad-b737-313-circumferential-butt-splices-and-bonded-doublers/documents"}}