{"id":"F2006B05933","name":"AD/PA-36/17 - Rudder Spar - Inspection","slug":"ad-pa-36-17-rudder-spar-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":136038,"registerId":"commonwealth-F2006B05933-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-36/17 - Rudder Spar - 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-36 (Pawnee Brave) Series Aeroplanes\n\n \n\nAD/PA-36/17 Rudder Spar - Inspection 4/77\n\nApplicability: All models with S/Nos. 36-7360001 to 36-7760003. Document:  Piper SB No. 518.\n\nCompliance: Within 100 hours time in service after 30 April 1977 and thereafter at intervals not exceeding 100 hours time in service until rudder is replaced.\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 is a discrete, single-issue safety directive from 1977 (as indicated by the '4/77' suffix). It has not expanded beyond its original purpose of addressing a specific rudder spar inspection requirement for a defined aircraft population. Airworthiness Directives are inherently narrow instruments by design."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory text","No defined terms section — all language is plain operational English","Single, straightforward compliance requirement with clear time trigger (100 hours time in service)","No cross-references to other legislation beyond generic 'Civil Aviation Regulations 1998' header","No conditional logic, exceptions, or nested provisions","Simple applicability test based solely on serial number range"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998.\n\n**What it does:** It requires owners and operators of specific Piper PA-36 \"Pawnee Brave\" agricultural aircraft to inspect the **rudder spar** (the main structural beam inside the aircraft's tail rudder) for defects.\n\n**Who it affects:** All Piper PA-36 model aircraft with serial numbers between 36-7360001 and 36-7760003.\n\n**What must be done:**\n- **First inspection:** Within 100 hours of flying time after 30 April 1977\n- **Repeat inspections:** Every 100 hours of flying time thereafter\n- **When it stops:** Only when the rudder is replaced\n\n**Why it matters:** The rudder spar is critical for controlling the aircraft. This AD was issued because of a safety concern identified in **Piper Service Bulletin No. 518** — likely a structural weakness or cracking risk that could lead to loss of control if not detected.\n\n**The bottom line:** If you own or operate one of these specific Pawnee Brave aircraft, you legally cannot skip these inspections. They're repetitive and mandatory until you replace the rudder entirely."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument, as written, applies to PA-36 aeroplanes with serial numbers 36-7360001 to 36-7760003 and establishes a repeating 100-hour rudder-spar inspection requirement until replacement. The text presents a single, focused change — the imposition of the inspection schedule and reference to Piper SB No. 518 — and does not indicate any broader or different scope than that stated."},"complexity_factors":["Narrow applicability limited to a serial-number range (36-7360001 to 36-7760003) requiring operators to check aircraft identity (Applicability).","Recurring inspection interval tied to time-in-service (every 100 hours) creates ongoing scheduling and tracking requirements (Compliance).","Compliance outcome depends on a referenced manufacturer service bulletin (Piper SB No. 518) for procedural detail not contained in the AD itself (Document).","The directive conditions cessation of recurring inspections on a remedial action (rudder replacement), introducing a cost-versus-recurring-inspection trade-off (Compliance).","Historic/absolute date reference (\"after 30 April 1977\") requires interpretation against aircraft records and may complicate retrospective compliance verification (Compliance)."],"plain_english_summary":"This airworthiness directive mandates recurring inspections of the rudder spar on Piper PA‑36 (Pawnee Brave) aeroplanes with serial numbers 36‑7360001 to 36‑7760003: inspect within 100 hours TIS after 30 April 1977 and every 100 hours thereafter until the rudder is replaced. It affects owners/operators and maintenance providers, imposes ongoing scheduling and cost burdens, creates a trade‑off between repeated inspections and one‑time rudder replacement, and references Piper Service Bulletin No. 518 for technical guidance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-36-17-rudder-spar-inspection","history":"/api/acts/ad-pa-36-17-rudder-spar-inspection/history","analysis":"/api/acts/ad-pa-36-17-rudder-spar-inspection/analysis","conflicts":"/api/acts/ad-pa-36-17-rudder-spar-inspection/conflicts","importantCases":"/api/acts/ad-pa-36-17-rudder-spar-inspection/important-cases","documents":"/api/acts/ad-pa-36-17-rudder-spar-inspection/documents"}}