{"id":"F2006L00359","name":"AD/EMB-120/41 - Bleed Air System","slug":"ad-emb-120-41-bleed-air-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116971,"registerId":"commonwealth-F2006L00359-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Embraer EMB-120 (Brasilia) Series Aeropl","sectionType":"division","heading":"Embraer EMB-120 (Brasilia) Series Aeroplanes","content":"### Embraer EMB-120 (Brasilia) Series Aeroplanes\n\n| AD/EMB-120/41 | Bleed Air System | 3/2006 |\n| ------------- | ---------------- | ------ |\n\n| Applicability: | All model EMB-120( ) aeroplanes.                                                                                                                                                                                                                                                                                                                                                                                                                                               |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | If not previously accomplished, replace the bleed air system shut-off and crossbleed valves part number (P/N) 979626-4-1 with valves P/N 979626-6 in accordance with Embraer Service Bulletin 120-36-0016 dated 30 October 2003 or later revision approved by the Centro Técnico Aeroespacial.                                                                                                                                                                                 |\n|                | Note: DAC (Brazil) AD 2005-12-03 refers.                                                                                                                                                                                                                                                                                                                                                                                                                                       |\n| Compliance:    | Within 5000 hours time in services after the effective date of this Directive.                                                                                                                                                                                                                                                                                                                                                                                                 |\n|                | This Airworthiness Directive becomes effective on 16 March 2006.                                                                                                                                                                                                                                                                                                                                                                                                               |\n| Background:    | The Brazilian Departamento de Aviação Civil (DAC) has advised that the aircraft manufacturer has conducted a review of the fuel system to ensure compliance with United States Special Federal Aviation Regulation (SFAR) 88.The review verified that the replacement of the current bleed air system shut-off and crossbleed valves with others featuring hermetically sealed switches was required to preclude a possible ignition source in the vicinity of the fuel tanks. |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n1 February 2006","sortOrder":0},{"sectionNumber":"AD/EMB-120/41","sectionType":"part","heading":"AD/EMB-120/41","content":"## AD/EMB-120/41","sortOrder":1},{"sectionNumber":"Bleed Air System","sectionType":"part","heading":"Bleed Air System","content":"## Bleed Air System","sortOrder":2},{"sectionNumber":"3/2006","sectionType":"part","heading":"3/2006","content":"## 3/2006","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":2,"scope_assessment":{"changed":false,"description":"The Directive's scope aligns with the stated safety objective: mandating valve replacement on all EMB-120 aeroplanes to eliminate a potential ignition source. It does not expand to other systems or aircraft types and limits action to the specified parts and procedure."},"complexity_factors":["Single, discrete technical action: replace specific valve P/N 979626-4-1 with P/N 979626-6 (low procedural complexity).","Applicability is broad but simple: all EMB-120 models (no model-by-model carve-outs).","Compliance window set at 5,000 flight hours — requires scheduling into maintenance cycles (moderate operational planning).","Mandates conformity with an Embraer Service Bulletin or later revision approved by the Centro Técnico Aeroespacial (relies on external document and regulator approval).","Parts availability and procurement cost fall to operators (direct financial and logistical burden).","Recordkeeping and evidence of compliance required to satisfy the Directive (administrative burden).","Safety rationale references an SFAR 88 compliance review — technical justification present but implementation requires maintenance access around fuel tanks (workscope and access constraints)."],"plain_english_summary":"This Directive requires all operators of Embraer EMB-120 aeroplanes to replace the bleed air shut-off and crossbleed valves (P/N 979626-4-1) with valves P/N 979626-6, following Embraer Service Bulletin 120-36-0016 (or later approved revision), within 5,000 hours. The Brazilian authority says the change fits hermetically sealed switches to remove a possible ignition source near fuel tanks; operators must obtain parts and perform the mandated maintenance under the approved procedures."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific safety defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating a particular hardware replacement to prevent ignition hazards near fuel tanks."},"complexity_factors":["Single, specific technical requirement (valve replacement)","Only one applicable aircraft model series","Straightforward compliance deadline (5000 hours time in service)","No nested exceptions or conditional logic","Minimal cross-referencing (only one referenced service bulletin and one Brazilian AD)","Short document (approximately 200 words of substantive content)","Single defined term (P/N for part number, in common usage)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Embraer EMB-120 (Brasilia) aircraft to replace bleed-air valves (PN 979626-4-1) with improved, hermetically sealed valves (PN 979626-6). \n\nIt matters because the old valves could spark near fuel tanks, risking ignition; affected operators in Australia must complete the replacement within 5,000 flight hours after 16 March 2006."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-120-41-bleed-air-system","history":"/api/acts/ad-emb-120-41-bleed-air-system/history","analysis":"/api/acts/ad-emb-120-41-bleed-air-system/analysis","conflicts":"/api/acts/ad-emb-120-41-bleed-air-system/conflicts","importantCases":"/api/acts/ad-emb-120-41-bleed-air-system/important-cases","documents":"/api/acts/ad-emb-120-41-bleed-air-system/documents"}}