{"id":"F2009L03922","name":"AD/BELL 412/31 - Fin to Tail Boom Junction - CANCELLED","slug":"ad-bell-412-31-fin-to-tail-boom-junction-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":81305,"registerId":"commonwealth-F2009L03922-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron 412 Series Helic","sectionType":"division","heading":"Bell Helicopter Textron 412 Series Helicopters","content":"### Bell Helicopter Textron 412 Series Helicopters\n\n| AD/BELL 412/31 | Fin to Tail Boom Junction | 12/2009 |\n| -------------- | ------------------------- | ------- |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                                                                                  |\n| ------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | This AD is cancelled on 19 November 2009.                                                                                                                                                                                                                                   |\n| Background:  | This unique Australian AD specified a once-only inspection of the fin-to-tailboom junction by May 1992. The AD was issued following discovery of a crack in an Australian Bell 212 helicopter and was not based on a manufacturer’s bulletin. The AD is no longer required. |\n\n![](image.001.png)\n\nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n30 September 2009","sortOrder":0},{"sectionNumber":"AD/BELL 412/31","sectionType":"part","heading":"AD/BELL 412/31","content":"## AD/BELL 412/31","sortOrder":1},{"sectionNumber":"Fin to Tail Boom Junction","sectionType":"part","heading":"Fin to Tail Boom Junction","content":"## Fin to Tail Boom Junction","sortOrder":2},{"sectionNumber":"12/2009","sectionType":"part","heading":"12/2009","content":"## 12/2009","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2570},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The legislation has not expanded beyond its original purpose; rather, it has been entirely cancelled. The original scope (mandating a one-time safety inspection) has been reduced to nil, eliminating all operational obligations rather than adding new ones."},"complexity_factors":["Single, unambiguous operative provision (cancellation)","No defined terms, interpretation sections, or schedules","No conditional logic, exceptions, or nested requirements","Minimal cross-referencing (refers only to the specific AD being cancelled)"],"plain_english_summary":"This document cancels a previous **Airworthiness Directive (AD)**—a mandatory aviation safety rule—that required owners of Bell 412 series helicopters to inspect the junction between the tail fin and tail boom for cracks.\n\n**What it used to require**\nThe original rule, issued in the early 1990s after a crack was discovered in a similar Australian helicopter, mandated a one-time inspection of this connection point by May 1992.\n\n**Why it was cancelled**\nAs of 19 November 2009, the Civil Aviation Safety Authority determined this specific inspection was no longer necessary for airworthiness or safety. The requirement has been completely removed from the regulatory framework.\n\n**Who is affected**\nOwners and operators of Bell 412 series helicopters are no longer legally required to carry out this specific inspection, though other maintenance obligations continue to apply."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled","history":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled/history","analysis":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled/analysis","conflicts":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled/conflicts","importantCases":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled/important-cases","documents":"/api/acts/ad-bell-412-31-fin-to-tail-boom-junction-cancelled/documents"}}