{"id":"F2006B06159","name":"AD/PC-6/9 - Rudder - Modification","slug":"ad-pc-6-9-rudder-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46971,"registerId":"commonwealth-F2006B06159-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-6/9 - Rudder - 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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Pilatus Porter PC-6 Series Aeroplanes\n\n \n\nAD/PC-6/9 Rudder - Modification 3/66\n\nApplicability: All models. Document: Pilatus SB No. 49. Compliance: Before 1 July 1966.\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":1,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1966. It has not expanded beyond its original narrow purpose of requiring a specific rudder modification on one aircraft type. The scope remains exactly as originally intended."},"complexity_factors":["Extremely short — only 4 substantive lines of regulatory text","No defined terms section","No cross-references to other legislation (only references a manufacturer document)","No conditional logic or exceptions","Simple structure: applicability → document reference → compliance deadline","Single, unambiguous requirement with fixed deadline"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\n- Requires owners and operators of **Pilatus Porter PC-6 series aeroplanes** (a type of single-engine turboprop aircraft commonly used for bush flying, skydiving, and cargo work) to modify the **rudder** (the movable surface on the tail that steers the aircraft left and right).\n\n**Who it affects:**\n- Anyone who owns, operates, or maintains a Pilatus PC-6 aircraft in Australia.\n\n**The requirement:**\n- Follow **Pilatus Service Bulletin No. 49** — this is the manufacturer's official instructions for how to do the modification.\n- **Deadline:** The work must be completed **before 1 July 1966**.\n\n**Why it matters:**\nAirworthiness Directives are legally binding. If you don't comply, you cannot legally fly the aircraft. This particular directive addresses a specific safety issue with the rudder that Pilatus identified — likely a structural weakness, control problem, or fatigue issue that could affect safe handling of the aircraft.\n\n**Historical note:** This directive dates from 1966 (hence \"3/66\" in the reference), so for any PC-6 still flying today, this modification would have been completed decades ago. However, the directive remains on the books as part of the regulatory record."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD's text sets a single, specific requirement: perform the rudder modification on all Pilatus PC-6 models in accordance with Pilatus SB No. 49 by the stated date. There is no indication in the supplied text that the directive's scope was altered from its stated purpose; it remains a targeted, model-wide mandatory modification with a fixed compliance deadline (see \"Applicability: All models.\", \"Document: Pilatus SB No. 49.\", \"Compliance: Before 1 July 1966.\")."},"complexity_factors":["Short, single-action directive (rudder modification) reduces procedural complexity.","Blanket applicability to all PC-6 models increases operational reach but keeps a single technical subject.","Mandatory compliance date creates a clear deadline but adds scheduling pressure.","Technical steps are not included in the AD; compliance requires consulting an external document (Pilatus SB No. 49), adding a dependency.","AD text does not specify exceptions, alternative means of compliance, cost, or enforcement detail, leaving those elements to other regulatory or operational processes."],"plain_english_summary":"This AD mandates a rudder modification for all Pilatus PC-6 models, issued by the Civil Aviation Safety Authority under the Civil Aviation Regulations. Compliance requires carrying out the modification in accordance with Pilatus Service Bulletin No. 49 by 1 July 1966. Aircraft operators/owners and maintenance organisations are legally responsible for meeting this deadline."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-6-9-rudder-modification","history":"/api/acts/ad-pc-6-9-rudder-modification/history","analysis":"/api/acts/ad-pc-6-9-rudder-modification/analysis","conflicts":"/api/acts/ad-pc-6-9-rudder-modification/conflicts","importantCases":"/api/acts/ad-pc-6-9-rudder-modification/important-cases","documents":"/api/acts/ad-pc-6-9-rudder-modification/documents"}}