{"id":"F2006B05458","name":"AD/PA-23/28 - Exhaust System - Inspection","slug":"ad-pa-23-28-exhaust-system-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46217,"registerId":"commonwealth-F2006B05458-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/28 - Exhaust System - Inspection","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)  Piper PA-23 (Apache and Aztec) Series Aeroplanes\n\n \n\nAD/PA-23/28 Exhaust System - Inspection 2/63\n\nApplicability: All models. Document: Piper SL No. 324C.\n\nCompliance: At intervals not exceeding 100 hours time in service after 5 February 1963.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a vintage 1963 Airworthiness Directive that has remained unchanged in scope. It addresses a specific, narrow safety issue (exhaust system integrity) for a specific aircraft type. There is no evidence of scope creep — it has not expanded to cover additional systems, aircraft types, or operational scenarios beyond the original exhaust inspection requirement."},"complexity_factors":["Extremely short document — only 4 substantive lines","Zero defined terms within the instrument itself (relies on external CASA definitions for 'time in service')","Single, unambiguous compliance requirement (100-hour interval)","No cross-references to other legislation beyond the enabling regulation (CAR 1998 Part 39)","No conditional logic, exceptions, or alternative compliance methods stated","Simple applicability statement ('All models') with no exclusions"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all **Piper PA-23 Apache and Aztec aircraft** (twin-engine planes commonly used for charter, training, and private flying).\n\n**What it requires:**\n- **Inspection of the exhaust system** — the pipes that carry hot gases away from the engine.\n- **How often:** Every 100 hours of \"time in service\" (actual flying hours, not just calendar time).\n- **Starting when:** After 5 February 1963.\n- **Technical reference:** Piper Service Letter No. 324C (the manufacturer's official repair/inspection instructions).\n\n**Why it matters:**\nExhaust system failures can cause carbon monoxide poisoning in the cabin, engine fires, or loss of engine power. This AD ensures cracks, corrosion, or damage are caught before they become dangerous. Owners and operators who ignore this face grounding of their aircraft and potential legal penalties.\n\n**Who must comply:**\n- Aircraft owners\n- Licensed aircraft maintenance engineers (LAMEs)\n- Operators of affected aircraft"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied text does not indicate any change to the directive's scope from a prior or original instrument. No prior scope or amendment history is provided in the text, so a change cannot be identified from the material given."},"complexity_factors":["Narrow, single-subject requirement (exhaust system inspection) reduces complexity.","Clear, time-based compliance interval (every 100 hours) simplifies scheduling.","Applicability to all models increases the number of affected aircraft and operational impact.","Procedural and technical detail is delegated to an external document (Piper SL No. 324C), requiring users to obtain and interpret that material.","Date-specific compliance commencement (after 5 February 1963) introduces a historical trigger that implementers must interpret against aircraft logbooks."],"plain_english_summary":"This Airworthiness Directive mandates recurring inspections of the exhaust system on all Piper PA‑23 (Apache/Aztec) aircraft, to be performed every 100 hours time‑in‑service beginning 5 February 1963. Owners/operators must carry out and fund the inspections and follow Piper Service Letter No. 324C for procedural details—imposing a recurring maintenance and scheduling burden to address safety risks."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-28-exhaust-system-inspection","history":"/api/acts/ad-pa-23-28-exhaust-system-inspection/history","analysis":"/api/acts/ad-pa-23-28-exhaust-system-inspection/analysis","conflicts":"/api/acts/ad-pa-23-28-exhaust-system-inspection/conflicts","importantCases":"/api/acts/ad-pa-23-28-exhaust-system-inspection/important-cases","documents":"/api/acts/ad-pa-23-28-exhaust-system-inspection/documents"}}