{"id":"F2006B04587","name":"AD/BELL 212/55 Amdt 1 - Main Rotor - Pillow Block Attachment Bolts","slug":"ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114324,"registerId":"commonwealth-F2006B04587-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 212/55 Amdt 1 - Main Rotor - Pillow Block Attachment Bolts","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \n![](image.002.png)  \nBell Helicopter Textron 212 Series Helicopters\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BELL 212/55 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nAD/BELL 212/55\n\nAmdt 1\n\n  \nMain Rotor \\- Pillow Block Attachment Bolts 8/2000\n\nApplicability: All models with main rotor yokes P/N 204-011-102-(all dash numbers) installed.\n\nRequirement: Action in accordance with Bell Helicopter Textron Alert Service Bulletin 212-90-62 Revision A.\n\nNote 1: FAA AD 92-23-01 refers.\n\nAircraft incorporating stainless steel main rotor yokes are excluded from this directive.\n\nNote 2: BHT Alert SB 212-92-80 refers.\n\nCompliance: As detailed in the Requirement document.\n\nThis Amendment becomes effective on 10 August 2000.\n\nBackground: There have been five cases of main rotor pillow block attachment bolt fatigue cracks reported. This AD is intended to prevent failure of the pillow block attachment bolts and consequent separation of the main rotor assembly. A Bell 212 operator has correctly pointed out that the requirements of the Bell Alert SB are not applicable to the stainless steel main rotor yoke assembly, and could result in the bolts being torqued incorrectly.\n\nThe original issue of this Airworthiness Directive became effective on 27 April 1995.\n\n![](image.003.png)  \n\nBernard Malcom Hole\n\nDelegate of the Civil Aviation Safety Authority 27 June 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 12 July 2000.\n\nAL 8/2000\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of the 1995 directive. It does not expand or contract the safety purpose; it merely corrects a technical error by excluding stainless steel yokes that were never meant to be covered. The core safety objective — preventing main rotor bolt failures — remains unchanged."},"complexity_factors":["Very short document (approximately 300 words)","Only 1 defined term implicitly used (P/N = Part Number)","Single requirement referencing an external technical document (Bell Service Bulletin)","One clear exclusion (stainless steel yokes)","No nested conditional logic or cross-references to other legislation","Straightforward compliance structure: identify applicability → follow external instructions → done"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections or replacement of main rotor pillow‑block attachment bolts on Bell 212 helicopters fitted with main rotor yokes P/N 204‑011‑102 (excluding stainless‑steel yokes), by following Bell Helicopter Textron Alert Service Bulletin 212‑90‑62 Rev A. \n\nIt responds to five fatigue‑crack findings that could lead to rotor separation, and corrects a 1995 error that had mistakenly applied requirements to stainless‑steel yokes."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment revokes the original AD and narrows the operative scope by excluding aircraft with stainless‑steel main rotor yokes. It replaces the prior requirement by directing compliance with Bell Alert Service Bulletin 212-90-62 Revision A and became effective 10 August 2000; the original AD became effective 27 April 1995."},"complexity_factors":["External dependency on Bell Helicopter Textron Alert Service Bulletin 212-90-62 Revision A for technical steps and timing","Specific applicability tied to a particular part number (P/N 204-011-102-(all dash numbers))","Exclusion for stainless‑steel yoke assemblies requires operator verification of materials","Revocation of a prior AD (AD/BELL 212/55) requires cross-referencing historical directives","Compliance timing and technical details are not reproduced in the AD but delegated to the service bulletin, increasing the need to consult another document"],"plain_english_summary":"Mechanically, this directive revokes the prior AD and requires Bell 212 operators with main rotor yokes P/N 204-011-102-(all dash numbers) to carry out the inspections and corrective actions set out in Bell Helicopter Textron Alert Service Bulletin 212-90-62 Revision A; helicopters with stainless‑steel main rotor yokes are excluded. It is issued to prevent fatigue cracking and potential separation of the main rotor. The Civil Aviation Safety Authority delegate requires operators to perform the specified inspections/repairs at the times in the service bulletin; operators pay compliance costs and must follow the torque/repair instructions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts","history":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts/history","analysis":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts/analysis","conflicts":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts/conflicts","importantCases":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts/important-cases","documents":"/api/acts/ad-bell-212-55-amdt-1-main-rotor-pillow-block-attachment-bolts/documents"}}