{"id":"F2008L02468","name":"AD/PA-31/90 - Rudder Trim Mechanism - CANCELLED","slug":"ad-pa-31-90-rudder-trim-mechanism-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":74415,"registerId":"commonwealth-F2008L02468-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Piper PA-31 Series Aeroplanes","sectionType":"division","heading":"Piper PA-31 Series Aeroplanes","content":"### Piper PA-31 Series Aeroplanes\n\n| AD/PA-31/90 | Rudder Trim Mechanism | 8/2008 |\n| ----------- | --------------------- | ------ |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                                                              |\n| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | This AD is cancelled on 31 July 2008.                                                                                                                                                                                                                   |\n| Background:  | This unique Australian AD required once-only inspection of the rudder trim mechanism in accordance with Piper SB No. 674. The AD required compliance within 100 hours TIS after March 1980, so all affected aircraft would have been modified long ago. |\n\n![](image.001.png)\n\nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n17 June 2008","sortOrder":0},{"sectionNumber":"AD/PA-31/90","sectionType":"part","heading":"AD/PA-31/90","content":"## AD/PA-31/90","sortOrder":1},{"sectionNumber":"Rudder Trim Mechanism","sectionType":"part","heading":"Rudder Trim Mechanism","content":"## Rudder Trim Mechanism","sortOrder":2},{"sectionNumber":"8/2008","sectionType":"part","heading":"8/2008","content":"## 8/2008","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1739},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This instrument simply terminates an existing spent directive. It does not expand, restrict, or alter the regulatory scope; it merely concludes the lifecycle of a requirement that has been fully complied with by all affected parties."},"complexity_factors":["Single operative provision (simple cancellation)","No defined terms or interpretation section","No cross-references to other legislation","Extremely short (under 200 words)","No conditional logic, exceptions, or procedural requirements"],"plain_english_summary":"**What this does**\n\nThis document officially cancels an old aviation safety directive (AD/PA-31/90) that required owners of Piper PA-31 aeroplanes to inspect their **rudder trim mechanism** — the control that helps keep the plane flying straight without the pilot constantly pushing the foot pedals.\n\n**Who it affects**\n\nOwners and operators of Piper PA-31 series aircraft. However, the original rule required the inspection to be done within 100 flight hours after March 1980, so every affected aircraft was modified decades ago.\n\n**Why it matters**\n\nThe Civil Aviation Safety Authority is cleaning up the rulebook. Because the safety deadline passed 28 years ago and all planes have long since been checked, the rule is now redundant. This cancellation formally removes it from force as of 31 July 2008 without affecting air safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled","history":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled/history","analysis":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled/analysis","conflicts":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled/conflicts","importantCases":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled/important-cases","documents":"/api/acts/ad-pa-31-90-rudder-trim-mechanism-cancelled/documents"}}