{"id":"F2007L02442","name":"AD/ATR 42/17 - Thermal/Acoustic Insulation Blankets","slug":"ad-atr-42-17-thermal-acoustic-insulation-blankets","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":67897,"registerId":"commonwealth-F2007L02442-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Avions de Transport Regional ATR 42 Seri","sectionType":"division","heading":"Avions de Transport Regional ATR 42 Series Aeroplanes","content":"### Avions de Transport Regional ATR 42 Series Aeroplanes\n\n| AD/ATR 42/17 | Thermal/Acoustic Insulation Blankets | 9/2007 |\n| ------------ | ------------------------------------ | ------ |\n\n| Applicability: | Model ATR 42-400 and ATR 42-500 aircraft, all serial numbers, except aircraft with modification 5117 or 5322, or Service Bulletin ATR42-25-0134 Revision 4, incorporated.                                                                                                                                                                                                                                                                                                                                                                               |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the requirements of EASA AD 2007-0164.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of30 August 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                               |\n|                | This Airworthiness Directive becomes effective on 30 August 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |\n| Background:    | The flammability characteristics of thermal/acoustic insulation material made from MPET may have been a contributing factor in certain incidents initiated by electrical short circuit behind a fuselage compartment side wall. Although ATR aircraft were not affected by similar incidents, DGAC France issued AD F-2005-211 to require improvement of the fire safety standard of insulation blankets installed on ATR aircraft. This new EASA AD retains the requirements of the DGAC AD and requires removal of insulation blankets over frame 24. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n10 July 2007","sortOrder":0},{"sectionNumber":"AD/ATR 42/17","sectionType":"part","heading":"AD/ATR 42/17","content":"## AD/ATR 42/17","sortOrder":1},{"sectionNumber":"Thermal/Acoustic Insulation Blankets","sectionType":"part","heading":"Thermal/Acoustic Insulation Blankets","content":"## Thermal/Acoustic Insulation Blankets","sortOrder":2},{"sectionNumber":"9/2007","sectionType":"part","heading":"9/2007","content":"## 9/2007","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive with a single, specific purpose: addressing flammability of insulation blankets in particular aircraft models. It has not expanded beyond its original safety intent."},"complexity_factors":["Short, single-purpose directive (approximately 200 words of substantive content)","Only 3 defined applicability criteria (model numbers, serial numbers, and 3 exemption conditions)","Single cross-reference to external document (EASA AD 2007-0164) for actual technical requirements","No nested conditional logic or exceptions to exceptions","Clear, linear structure: applicability → requirement → compliance → background","Technical aviation terminology present but explained through context (e.g., 'frame 24', 'MPET')"],"plain_english_summary":"This AD mandates removal or replacement of metallized PET (MPET) thermal/acoustic insulation blankets in certain ATR 42-400/500 aircraft because the material is more flammable and could increase post‑short‑circuit fire risk. It affects operators of those models unless they already have the specified modifications or service bulletin installed. Compliance follows EASA AD 2007‑0164 and was required by 30 August 2007."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This directive implements and adopts the safety requirements already set out by DGAC France and retained by EASA in AD 2007-0164. It does not expand the safety measures beyond those retained requirements; it simply applies them in Australian jurisdiction and sets a revised effective date. In other words, it preserves the original safety-focused scope (require removal/modification of specified insulation blankets) rather than broadening the subject matter or adding new categories of mandatory work."},"complexity_factors":["Short, single-purpose instrument (one airworthiness directive)","Narrow applicability (two specific ATR 42 variants) with three explicit exclusions (mod 5117, mod 5322, Service Bulletin ATR42-25-0134 Rev 4)","Primary operative text is a cross-reference to an external EASA AD (EASA AD 2007-0164) rather than detailed technical steps set out in this document","Minor conditional logic (apply unless exclusions are present)","One clear technical focus (insulation blankets, MPET material, removal over frame 24) and an explicit effective date revision"],"plain_english_summary":"**What this directive changes (mechanically)\n\n- Requires operators of certain ATR 42 aeroplanes to carry out the corrective actions set out in EASA Airworthiness Directive (AD) 2007-0164.  In practice that AD requires inspection/removal and replacement or modification of thermal/acoustic insulation blankets — specifically addressing blankets made from MPET and removal of blankets over frame 24 — to meet an improved fire‑safety standard.\n\n- Applies to: Model ATR 42-400 and ATR 42-500 aircraft, all serial numbers, except those that already have modification 5117 or 5322 incorporated, or have incorporated Service Bulletin ATR42-25-0134 Revision 4.  (If one of those modifications or the listed service bulletin is already fitted, the AD does not apply to that aeroplane.)\n\n- Compliance timing: The AD adopts the compliance requirements in the EASA AD and becomes effective on 30 August 2007 (the directive notes a revised effective date).\n\n- Who decides and who pays: The regulator (Civil Aviation Safety Authority adopting the EASA AD) requires compliance; aircraft operators and their maintenance organisations must carry out the work and bear the direct costs (labour, parts, aircraft downtime). Maintenance suppliers and parts manufacturers will be the market suppliers who deliver the work or parts.\n\nWhy the regulator says this matters\n\n- Stated purpose: Tests and incident investigations indicated the flammability characteristics of thermal/acoustic insulation made from MPET (a material used in some insulation blankets) may have contributed to fire propagation in incidents where an electrical short occurred behind a fuselage side wall. DGAC France issued an AD to address this risk on ATR types, and EASA's AD retains those requirements. The CASA directive adopts EASA AD 2007-0164 to implement the same corrective actions in Australia.\n\nAnalytical note on incentives, costs and trade‑offs (concrete mechanisms)\n\n- Safety mechanism: Removing or modifying the specified insulation blankets (and replacing them with material that meets the improved fire‑safety standard) reduces available combustible material in zones where an electrical short could ignite it; the AD specifically targets blankets over frame 24 as a required removal area.\n\n- Direct costs and who bears them: Operators pay for parts and maintenance labour and for the aircraft downtime needed to perform the work. If replacements or approved modifications are required, those are incurred by the operator. Maintenance organisations and parts suppliers gain work and revenue from the mandated changes.\n\n- Compliance burden and implementation risk: The AD delegates the technical detail to the EASA AD and the referenced service bulletin, so compliance requires access to and correct interpretation of those external documents. Risks include misidentifying blanket material or area, performing incorrect replacement material or not installing approved modifications, and potentially longer-than-expected aircraft grounding if parts are scarce.\n\n- Behavioural change: Operators must inspect aircraft records and physical installations, incorporate approved modifications or service bulletin work where required, or remove/replace the listed blankets. Operators who already incorporated mod 5117, mod 5322 or SB ATR42-25-0134 Rev 4 do not need to repeat the work for the same purpose.\n\n- Distribution of effects: The safety benefit (reduced fire risk) is spread across passengers, crew and the operator's asset protection. The costs are concentrated on operators (and indirectly passengers if downtime affects schedules); maintenance and parts suppliers receive concentrated commercial benefit from the required work.\n\nSource references within the directive: applicability exclusions are set out under \"Applicability\"; the operative action is \"Action in accordance with the requirements of EASA AD 2007-0164\" under \"Requirement\"; effective date and compliance timing are under \"Compliance\"; rationale is in \"Background.\""},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets","history":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets/history","analysis":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets/analysis","conflicts":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets/conflicts","importantCases":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets/important-cases","documents":"/api/acts/ad-atr-42-17-thermal-acoustic-insulation-blankets/documents"}}