{"id":"F2009L03932","name":"AD/PR/1 - Pitch Lock Cylinder - Modification - CANCELLED","slug":"ad-pr-1-pitch-lock-cylinder-modification-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":81332,"registerId":"commonwealth-F2009L03932-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PR/1 - Pitch Lock Cylinder - Modification - CANCELLED","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 20.2\ntitle: AIRCRAFT\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n \n\nAIRWORTHINESS DIRECTIVE\n\nOn the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive AD/PR/1.\n\n### Propellers - Variable Pitch - Dowty Rotol\n\n| AD/PR/1 | Pitch Lock Cylinder - Modification | 12/2009 |\n| --- | --- | --- |\n\n\n \n\n| Requirement: | CANCELLED. |\n| --- | --- |\n|  | This AD is cancelled on 19 November 2009. |\n| Background: | This unique Australian AD was no longer required.  It was older than 40 years. |\n\n\n![](image.001.png)\n\nJames Coyne  Delegate of the Civil Aviation Safety Authority\n\n30 September 2009\n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2592},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":true,"description":"The directive has transitioned from mandating specific mechanical modifications to aircraft propellers to being completely revoked and of no effect, removing all compliance obligations after 40 years."},"complexity_factors":["Single operative provision (cancellation)","No defined terms or interpretation section","No cross-references to other legislation","Minimal procedural content (4 paragraphs/tables only)"],"plain_english_summary":"**This document scraps an outdated aircraft safety rule.**\n\nThe Civil Aviation Safety Authority has cancelled **Airworthiness Directive AD/PR/1**, which previously required modifications to **pitch lock cylinders** (safety mechanisms that stop propellers from changing blade angle unexpectedly) on Dowty Rotol variable pitch propellers.\n\n**What changes:**\n- Aircraft owners and maintenance engineers no longer need to carry out the specific modifications mandated by the original directive\n- The cancellation took effect on 19 November 2009\n- The rule was cancelled because it was over 40 years old and no longer necessary for safety\n\nThis is a housekeeping measure to remove obsolete regulatory requirements from the books."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled","history":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled/history","analysis":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled/analysis","conflicts":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled/conflicts","importantCases":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled/important-cases","documents":"/api/acts/ad-pr-1-pitch-lock-cylinder-modification-cancelled/documents"}}