{"id":"F2006B06125","name":"AD/PC-6/22 - Wing Fixed Spoilers - Installation","slug":"ad-pc-6-22-wing-fixed-spoilers-installation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46896,"registerId":"commonwealth-F2006B06125-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-6/22 - Wing Fixed Spoilers - Installation","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-6/22 Wing Fixed Spoilers - Installation 12/67\n\nApplicability: All models prior to S/No. 656. Document: Pilatus SB No. 76.\n\nCompliance: Before 1 April 1968.\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 airworthiness directive from 1967 (indicated by the '12/67' suffix). It has not expanded beyond its original narrow purpose of mandating spoiler installation on early PC-6 aircraft. The scope remains precisely limited to the specific airframe modification identified in the original safety assessment."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory content","No defined terms section — all language is plain technical aviation terminology","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Simple conditional structure: single applicability criterion (serial number threshold) and single compliance deadline","No exceptions, exemptions, or nested conditions","References only one external technical document (Pilatus SB No. 76) for implementation details"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific Pilatus Porter PC-6 aircraft to install fixed spoilers on the wings.\n\n**Who it affects:**\n- Owners and operators of Pilatus Porter PC-6 series aeroplanes with **serial numbers below 656** (all models built before serial number 656)\n\n**What it requires:**\n- Installation of wing fixed spoilers following the instructions in **Pilatus Service Bulletin No. 76**\n- This work must be completed **before 1 April 1968**\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety instructions. They typically issue when the manufacturer or regulator discovers a design flaw, wear pattern, or missing feature that could affect flight safety. In this case, the spoilers (devices on the wing that disrupt airflow to reduce lift and increase drag) were apparently not fitted to early production models but were deemed necessary for safe operation — likely to improve landing performance or controllability.\n\nFailure to comply means the aircraft cannot legally fly in Australian airspace."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is clearly limited to Pilatus PC-6 series aeroplanes with serial numbers prior to S/No. 656 and to the single action of installing wing fixed spoilers per Pilatus SB No. 76 by 1 April 1968. There is no indication in the provided text that the scope has been broadened or narrowed from an earlier intent; the instrument itself sets a narrow, specific requirement (see \"Applicability\" and \"Compliance\")."},"complexity_factors":["Short, single-action requirement (install wing fixed spoilers) with a single firm deadline.","Narrow applicability limited to aircraft with serial numbers prior to S/No. 656.","Dependency on an external technical document (Pilatus SB No. 76) — requires operators to obtain and follow that Service Bulletin for details.","No stated alternative compliance routes, exemptions, or transitional arrangements in the text — reduces procedural complexity but increases implementation rigidity.","Lack of explanatory material or stated rationale in the AD increases background uncertainty about intent and expected effects, requiring consultation of other materials for context."],"plain_english_summary":"This AD mandates installation of wing fixed spoilers on Pilatus PC‑6 aeroplanes with serial numbers prior to S/No. 656, to be done in accordance with Pilatus Service Bulletin No. 76 by 1 April 1968. It affects owners/operators of those aircraft, who bear the cost and scheduling burden; compliance is enforced by the Civil Aviation Safety Authority via the directive."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation","history":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation/history","analysis":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation/analysis","conflicts":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation/conflicts","importantCases":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation/important-cases","documents":"/api/acts/ad-pc-6-22-wing-fixed-spoilers-installation/documents"}}