{"id":"F2009L03424","name":"AD/TPE 331/11 - High Speed Pinion Bearing Assembly - Replacement - CANCELLED","slug":"ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":141010,"registerId":"commonwealth-F2009L03424-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AlliedSignal (Garrett/AiResearch) Turbin","sectionType":"division","heading":"AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series","content":"### AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series\n\n| AD/TPE 331/11 | High Speed Pinion BearingAssembly - Replacement | 10/2009 |\n| ------------- | ----------------------------------------------- | ------- |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                   |\n| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n|              | This AD is cancelled on 24 September 2009.                                                                                                                                                                   |\n| Background:  | This unique Australian AD specified action in accordance with Airesearch SBNo. 659 before installation in an aircraft following the next major re-conditioning after May 1972. The AD is no longer required. |\n\n![](image.001.png)\n\nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n14 August 2009","sortOrder":0},{"sectionNumber":"AD/TPE 331/11","sectionType":"part","heading":"AD/TPE 331/11","content":"## AD/TPE 331/11","sortOrder":1},{"sectionNumber":"High Speed Pinion BearingAssembly - Repl","sectionType":"part","heading":"High Speed Pinion BearingAssembly - Replacement","content":"## High Speed Pinion Bearing  \nAssembly - Replacement","sortOrder":2},{"sectionNumber":"10/2009","sectionType":"part","heading":"10/2009","content":"## 10/2009","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1604},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This instrument serves a singular, specific purpose: to cancel the previous Airworthiness Directive. Its scope is limited entirely to revoking the earlier requirements regarding pinion bearing assembly replacement, with no expansion beyond this cancellation function."},"complexity_factors":["Single operative provision cancelling previous requirements","No defined terms or interpretation sections","No conditional logic, exceptions, or procedural steps"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) that cancels an earlier safety rule affecting certain aircraft turbine engines.\n\n**What it does:** This document officially scraps a previous directive (AD/TPE 331/11) that required aircraft operators to replace high-speed pinion bearing assemblies in AlliedSignal (Garrett/AiResearch) TPE 331 series turbine engines. The old rule mandated that specific maintenance actions (following Airesearch Service Bulletin No. 659) had to be completed before installing these engines in aircraft following major re-conditioning work performed after May 1972.\n\n**Who it affects:** Aircraft operators, maintenance organisations, and engineers who work with TPE 331 turbine engines.\n\n**Why it matters:** The safety risk that originally justified the bearing replacement requirement no longer exists, so CASA has removed the obligation. Operators no longer need to comply with the previous directive."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled","history":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled/history","analysis":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled/analysis","conflicts":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled/conflicts","importantCases":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled/important-cases","documents":"/api/acts/ad-tpe-331-11-high-speed-pinion-bearing-assembly-replacement-cancelled/documents"}}