{"id":"F2006B08818","name":"AD/DC4/13 - Cabin Ventilator Exhaust - Rework","slug":"ad-dc4-13-cabin-ventilator-exhaust-rework","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52233,"registerId":"commonwealth-F2006B08818-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DC4/13 - Cabin Ventilator Exhaust - Rework","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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Douglas DC4 Series Aeroplanes\n\n \n\nAD/DC4/13 Cabin Ventilator Exhaust - Rework NK\n\nDocument: 1. Douglas SB (DC4) No. 32, revised 14 February 1949; or\n\n \n\n2. FAA AD 47-12-1; or\n\n \n\n3. ANO 105.1.16.2.5.12, Issue 2.\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\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This appears to be a standard, narrow airworthiness directive focused on a specific mechanical issue (cabin ventilator exhaust) for a specific aircraft type (DC-4). There is no indication of scope creep — it does exactly what its title suggests and references only the original technical sources from the 1940s."},"complexity_factors":["Extremely short document — essentially a reference to external technical documents rather than detailed regulatory text","Only 3 external references provided (Douglas Service Bulletin, FAA AD, and ANO — Air Navigation Order)","No defined terms section — relies entirely on external technical documentation","No conditional logic or exceptions within the text itself","Single, straightforward mechanical requirement (rework exhaust system)","Minimal cross-referencing within the document itself (all references are to external sources)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** for **Douglas DC-4 aircraft** — a type of four-engine propeller plane that was common in the 1940s-1960s.\n\n**What it does:**\nThis directive orders owners and operators of DC-4 planes to **rework (repair or modify) the cabin ventilator exhaust system**. The exhaust system vents air from inside the cabin to the outside. If this isn't working properly, it could cause safety problems — potentially including carbon monoxide entering the cabin or inadequate ventilation.\n\n**Who it affects:**\n- Anyone who owns or operates a Douglas DC-4 series aircraft in Australia\n- Maintenance engineers who work on these planes\n- The Civil Aviation Safety Authority (CASA), which enforces these rules\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety orders. If you don't comply, you can't legally fly the aircraft. This particular AD references older documents from 1949 (a Douglas service bulletin) and 1947 (an American FAA directive), suggesting it's addressing a long-standing design issue that could affect flight safety if left unaddressed.\n\n**Key point:** This is a **mandatory maintenance requirement**, not optional. The \"NK\" notation likely indicates this is a non-kit modification (meaning you don't need a specific parts kit to do the work)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Based on the text provided, the AD confines its application to Douglas DC4 series aeroplanes and mandates rework of the cabin ventilator exhaust by reference to three specific documents. The instrument’s scope as presented is consistent with that single technical action and does not indicate any expansion or narrowing beyond requiring the rework per the listed documents."},"complexity_factors":["Directive text is very short and delegates technical requirements to three external documents (Douglas SB No. 32; FAA AD 47-12-1; ANO 105.1.16.2.5.12 Issue 2), increasing reliance on external sources for implementation.","Multiple alternative compliance documents are listed, creating potential variability in methods, costs and interpretation.","The AD text as supplied does not specify compliance timing, inspection intervals, or record-keeping details, requiring operators to consult the referenced documents or regulator guidance.","Cross-jurisdictional reference to an FAA AD introduces potential for differing standards or terminology between documents.","Instrument scope is narrow (only Douglas DC4 series and the cabin ventilator exhaust) but technical and operational details are opaque without the referenced documents."],"plain_english_summary":"This AD requires owners and operators of Douglas DC‑4 series aircraft to have the cabin ventilator exhaust reworked, complying with one of three specified external documents.  \n\nIt affects aircraft owners, operators and maintenance organisations, shifts the cost and scheduling burden to them, and matters because it addresses an airworthiness concern by mandating a defined rework method chosen from the listed compliance documents."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework","history":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework/history","analysis":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework/analysis","conflicts":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework/conflicts","importantCases":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework/important-cases","documents":"/api/acts/ad-dc4-13-cabin-ventilator-exhaust-rework/documents"}}