{"id":"F2008L04387","name":"AD/B737/191 Amdt 1 - Strut Insulation Blankets","slug":"ad-b737-191-amdt-1-strut-insulation-blankets","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":76344,"registerId":"commonwealth-F2008L04387-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/B737/191 Amdt 1 | Strut Insulation Blankets | 13/2008 |\n| ------------------ | ------------------------- | ------- |\n\n| Applicability: | Model 737-600, -700, -700C, -800, and -900 series aircraft, as identified in Boeing Special Attention Service Bulletin 737-54-1045 dated 25 July 2007, or later FAA approved revision.                                                                                                                                                                                                                                                                                                                |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2008-21-02 Amdt 39-15686.                                                                                                                                                                                                                                                                                                                                                                                                              |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of18 December 2008.                                                                                                                                                                                                                                                                                                                                                                                                           |\n|                | This Amendment becomes effective on 18 December 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n| Background:    | The FAA received reports of damaged engine aft strut insulation blankets. Such damage could result in exposure of the lower surface of the strut to extreme high temperatures, consequent creation of a source of fuel ignition, and increased risk of a fuel tank explosion and fire.Amendment 1 is issued in response to a new FAA AD, which adds aircraft to the applicability and requires installation of a new insulation blanket and new cover plate on the left and right side engine struts. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n28 October 2008","sortOrder":0},{"sectionNumber":"AD/B737/191 Amdt 1","sectionType":"part","heading":"AD/B737/191 Amdt 1","content":"## AD/B737/191 Amdt 1","sortOrder":1},{"sectionNumber":"Strut Insulation Blankets","sectionType":"part","heading":"Strut Insulation Blankets","content":"## Strut Insulation Blankets","sortOrder":2},{"sectionNumber":"13/2008","sectionType":"part","heading":"13/2008","content":"## 13/2008","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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"This Amendment 1 expands the original directive's scope. The background explicitly states it 'adds aircraft to the applicability' (more 737 models covered) and upgrades the requirement from mere inspection to mandatory 'installation of a new insulation blanket and new cover plate.' The directive has grown from its original form to cover more aircraft and mandate more extensive physical modifications."},"complexity_factors":["Very short document (approximately 200 words)","Only 1 defined term implicitly referenced (the FAA AD number)","Single cross-reference to external FAA document","No nested conditional logic or exceptions","Straightforward applicability table with clear aircraft models","Simple compliance requirement: 'do what the FAA says' with one revised date"],"plain_english_summary":"This FAA Airworthiness Directive mandates inspection and replacement with new insulation blankets and cover plates on engine struts of certain Boeing 737-600/700/700C/800/900 series aircraft to eliminate damaged insulation. It affects owners/operators of airplanes identified in Boeing’s July 2007 service bulletin. The amendment expands affected models and now requires installation of new parts to prevent heat-induced fires or fuel tank ignition."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 expands the original AD by adding aircraft to the applicability list and by requiring installation of a new insulation blanket and new cover plate on both left and right engine struts, as described in the Background and Requirement sections. Effective date revised to 18 December 2008 (sources: Background; Compliance; Requirement)."},"complexity_factors":["Applicability limited to specific Boeing 737 variants identified in Boeing Special Attention Service Bulletin 737-54-1045 dated 25 July 2007 (source: Applicability).","Normative cross-reference to FAA AD 2008-21-02 for technical requirements rather than reproducing technical detail (source: Requirement: Action in accordance with FAA AD 2008-21-02).","Revised effective date and mandatory compliance timing (source: Compliance: revised effective date of 18 December 2008).","Amendment adds aircraft to applicability and prescribes additional hardware (new insulation blankets and cover plates) for left and right engine struts (source: Background: Amendment 1).","Implementation requires procurement and maintenance work by operators and record-keeping to demonstrate compliance (implied by Requirement/Compliance statements)."],"plain_english_summary":"**What it does:** Requires operators of specified Boeing 737-600/700/700C/800/900 series aeroplanes to modify the engine aft strut insulation by installing new insulation blankets and new cover plates in line with FAA Airworthiness Directive 2008-21-02. The amendment takes effect 18 December 2008.\n\n**Who it affects and why it matters:** Affects aircraft operators and maintenance providers who must pay for parts, labour and compliance actions to reduce the risk that damaged strut insulation exposes hot surfaces that could ignite fuel."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets","history":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets/history","analysis":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets/analysis","conflicts":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets/conflicts","importantCases":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets/important-cases","documents":"/api/acts/ad-b737-191-amdt-1-strut-insulation-blankets/documents"}}