{"id":"F2006B02436","name":"AD/APU/2 - Inspection, Placard, Operational Limitations and/or Modification","slug":"ad-apu-2-inspection-placard-operational-limitations-and-or-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41692,"registerId":"commonwealth-F2006B02436-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/APU/2 - Inspection, Placard, Operational Limitations and/or Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Auxiliary Power Units\n\n \n\nAD/APU/2 Inspection, Placard, Operational NK\n\nLimitations and/or Modification\n\n \n\nApplicability: Airesearch Model No. GTCP660-4 with S/Nos. P-37501 to P-37723 and Model No. GTC660-4R with S/Nos. P-101 to P-124 not modified in accordance with Airesearch SB No. GTCP660-49-3039.\n\n \n\nDocument: FAA AD 75-05-17 Amendment No. 39-2357. Compliance:  As detailed in the requirement document.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The Schedule as provided applies to a narrowly specified set of Airesearch APU serial numbers and excludes units modified per a named service bulletin. It adopts FAA AD 75-05-17 as the operative requirement for inspections, placards, operational limitations and/or modification. There is no indication within the text supplied that the scope has been altered from that stated intent: applicability, the exception, and the reference to the FAA AD together define the scope."},"complexity_factors":["Delegation of substantive requirements to an external document (FAA AD 75-05-17) rather than containing procedural detail within the Schedule entry.","Serial-number-specific applicability (two narrow serial-number ranges) requiring accurate records to determine whether an APU is in scope.","An explicit exception for units modified per Airesearch SB No. GTCP660-49-3039, which requires proof of modification to establish out-of-scope status.","Lack of detail in the Schedule about inspection intervals, technical procedures, and costs (all deferred to the FAA AD), creating dependence on another document for compliance obligations.","Cross-jurisdictional reference (Australian Schedule referencing a US FAA AD), which can create practical questions about interpretation, amendment timing, and version control of the operative requirement."],"plain_english_summary":"This Schedule entry applies an airworthiness directive to specific Airesearch APUs (listed serial ranges) and incorporates FAA AD 75-05-17 by reference. Operators and maintenance organisations must follow the inspections, placarding, operational limits and/or modifications required by that FAA AD unless their unit was already modified per Airesearch SB GTCP660-49-3039.\n\nPractical effect: affected owners bear the cost and must demonstrate serial-number and modification status; the Schedule delegates technical detail and compliance timing to the referenced FAA AD."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted Airworthiness Directive addressing a specific safety issue in specific APU models. It has not expanded beyond its original purpose of mandating safety actions for these particular units."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined model/serial number ranges in the applicability section","Single cross-reference to an external FAA document for detailed compliance requirements","No nested conditional logic or exceptions within the text itself","Standardized regulatory format with clear applicability and compliance sections"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA). It is a mandatory safety order for specific aircraft auxiliary power units (APUs) — essentially backup generators that provide power to aircraft when the main engines are off.\n\n**What it does:**\n- Requires owners and operators of specific Airesearch GTCP660-4 and GTC660-4R auxiliary power units to perform inspections, install warning placards, impose operational limits, and/or make modifications.\n- These actions are required because the FAA (US aviation regulator) identified a safety issue in these units, and Australia is adopting that US safety order.\n\n**Who it affects:**\n- Owners and operators of aircraft with Airesearch Model GTCP660-4 APUs with serial numbers P-37501 to P-37723, and Model GTC660-4R APUs with serial numbers P-101 to P-124.\n- Only applies if the unit has **not** already been modified according to Airesearch Service Bulletin GTCP660-49-3039.\n\n**Why it matters:**\n- Airworthiness Directives are legally binding. Non-compliance means the aircraft cannot fly legally in Australian airspace.\n- The directive addresses potential safety defects that could affect aircraft operation or passenger safety.\n\n**Compliance:**\n- Operators must follow the detailed requirements in the referenced FAA document (AD 75-05-17, Amendment 39-2357)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification","history":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification/history","analysis":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification/analysis","conflicts":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification/conflicts","importantCases":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification/important-cases","documents":"/api/acts/ad-apu-2-inspection-placard-operational-limitations-and-or-modification/documents"}}