{"id":"F2006B01897","name":"AD/A320/152 - Auxiliary Power Unit Alternating Current Generator","slug":"ad-a320-152-auxiliary-power-unit-alternating-current-generator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41093,"registerId":"commonwealth-F2006B01897-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A320/152 - Auxiliary Power Unit Alternating Current Generator","content":"![](image.001.png)\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/152 Auxiliary Power Unit Alternating Current\n\nGenerator\n\n  \n4/2004\n\nApplicability: A319, A320 and A321 series aeroplanes, all serial numbers, equipped with Hamilton Sundstrand Auxiliary Power Unit (APU) alternating current (AC) generator part number (P/N) 5906732, 5909006 or 5910047 with modification up to 17 incorporated.\n\nNote 1: Documentation from both Airbus and the French Direction Générale de l’Aviation Civile refer to the AC generators having amendments up to 17 rather than modifications.\n\nNote 2: No action is required by this Airworthiness Directive for aircraft that have embodied Airbus Modification 32614 during production or incorporated Airbus Industrie Service Bulletin (SB) A320-24-1106 whilst in service, provided that no generator has been replaced since the modification or SB was incorporated.\n\nRequirement: Unless already accomplished, replace all four bolts that retain the electrical receptacle of the APU AC generator with bolts P/N 5910191-30 and lock wire the bolts in accordance with the instruction given in SB A320-24-1106 (Hamilton Sundstrand Goodrich Power Systems SB 90EGS01AG-24-18 is also applicable).\n\nNote 3: DGAC AD F-2004-019 refers.\n\nCompliance: Before 30 October 2005.\n\nThis Airworthiness Directive becomes effective on 15 April 2004.\n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/152 (continued)\n\nBackground: The DGAC has advised that an operator reported a blast in the APU compartment, that blew open the APU compartment doors, damaging aircraft’s tail cone structure and the left elevator surface.\n\nAnalysis revealed, that vibrations in APU AC generators loosened the electrical receptacle retaining bolts, which lead to oil vapor leakage. This leakage, associated with an electrical arc at the electrical receptacle, was determined to be the cause of the blast.\n\n![](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 4 March 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 24 March 2004.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The AD implements a narrowly targeted corrective action to address the unsafe condition described in the Background (loosened bolts causing oil‑vapour leakage and an APU compartment blast) by mandating replacement and lock‑wiring of specified bolts on specified generator P/Ns (Requirement; Applicability). It does not expand the fleet or component types beyond that causal set, but it does create a compliance obligation for operators who must procure parts and perform the work by the stated date (Compliance). Exemptions are limited to aircraft that have already embodied Airbus Mod 32614 or SB A320‑24‑1106 and have not since replaced the generator (Note 2). The CASA delegate issued the directive under CASR 1998 subreg 39.1(1) (front matter)."},"complexity_factors":["Precise applicability keyed to generator part numbers and modification/amendment status (Applicability).","Conditional exemption depending on whether Airbus Mod 32614 or SB A320‑24‑1106 has been embodied and whether the generator has been replaced since (Note 2).","Mandated use of a specific replacement bolt P/N (5910191‑30) and lock‑wiring method referenced to an external service bulletin (Requirement; SB A320‑24‑1106 / Hamilton Sundstrand SB 90EGS01AG‑24‑18).","Fixed compliance deadline requiring operators to schedule maintenance and parts procurement by a set date (Compliance).","Cross‑references to foreign authority and other ADs (DGAC AD F‑2004‑019) which may require aligning records and actions across jurisdictions (Note 3).","Operational safety rationale rests on a technical failure sequence (vibration → loosened bolts → oil vapour + electrical arc → blast) that requires both inspection/rectification and potential supply-chain action (Background).","Minor textual ambiguity between the terms 'modification' and 'amendment' in the documentation (Note 1), which can complicate interpretation of compliance history.","Legal basis is a delegated AD under CASR 1998 subreg 39.1(1), concentrating decision authority with the CASA delegate (front matter)."],"plain_english_summary":"Requires replacement and lock‑wiring of the four bolts that hold the APU AC generator electrical receptacle on Airbus A319/A320/A321 aircraft fitted with Hamilton Sundstrand generators P/N 5906732, 5909006 or 5910047 (modifications up to 17). Operators that have embodied Airbus Mod 32614 or SB A320‑24‑1106 (and have not since replaced the generator) are exempt.\n\nThe stated purpose is to stop loosened bolts that led to oil‑vapour leakage and an APU compartment blast. Operators must buy parts, schedule maintenance and comply before 30 October 2005; the AD was issued under CASR 1998 subreg 39.1(1)."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, targeted airworthiness directive addressing a specific identified safety defect. The scope remains precisely limited to the unsafe condition described in the background — vibration-induced bolt loosening on specific APU generators. There is no evidence of scope creep beyond the original safety purpose."},"complexity_factors":["Single, specific mechanical action required (bolt replacement)","Limited applicability: only three specific aircraft models with specific part numbers","Clear exemption clause for aircraft already modified","Single compliance deadline with no conditional timing","No nested definitions or cross-referenced legislative provisions","Technical content is procedural rather than legal in complexity"],"plain_english_summary":"This AD mandates that operators of certain Airbus A319/A320/A321 aircraft fitted with Hamilton Sundstrand APU generators (P/N 5906732, 5909006, 5910047) replace four generator bolts with improved parts (P/N 5910191-30) and secure them with lockwire. It follows an APU-compartment explosion caused by vibration-loosened bolts, leaking oil, and an ignition that damaged the tail.\n\nCompliance is mandatory by 30 October 2005; the AD is effective 15 April 2004."}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator","history":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator/history","analysis":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator/analysis","conflicts":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator/conflicts","importantCases":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator/important-cases","documents":"/api/acts/ad-a320-152-auxiliary-power-unit-alternating-current-generator/documents"}}