{"id":"F2006B04719","name":"AD/BELL 47/98 - Main Rotor Grip","slug":"ad-bell-47-98-main-rotor-grip","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44483,"registerId":"commonwealth-F2006B04719-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 47/98 - Main Rotor Grip","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)  \nBell Helicopter Textron 47 (All Variants) Series Helicopters\n\nAD/BELL 47/98 Main Rotor Grip 1/92\n\nApplicability: Model 47G2, 47G2A, 47G2A1, 47G3, 47G3B1, 47G3B2, 47G3B2A, 47G4, 47G4A,\n\n47G5, 47G5A, 47J, 47J2 and 47J2A helicopters, with main rotor grip part number 47-120-252-11, installed.\n\nRequirement: Visually inspect the M/R grip and determine if one of the following serial numbers is installed:\n\nIT \\- 0251, 0253, 0254, 0255, 0256, 0257, 0260, 0261, 0262, 0263, 0264, 0265, 0267,\n\n0268, 0270, 0271, 0272, 0273, 0274, 0275, 0276, 0277, 0278, 0279, 0280, 0281,\n\n0282, 0284, 0285, 0286, 0289, 0290, 0291, 0293, 0294, 0295, 0296, 0297, 0299,\n\n0300, 0302, 0303, 0306, 0308, 0312, 0313, 0315, 0316, 0317, 0319, 0323, 0324,\n\n0326, 0327, 0328, 0329, 0330, 0333, 0334, 0335\n\nITM \\- 0005, 0007, 0022, 0046, 0077, 0096, 0109, 0112, 0114, 0115, 0125, 0128,\n\n0133, 0155, 0161, 0165, 0166, 0167, 0168, 0170, 0171, 0178, 0182, 0183, 0185,\n\n0187, 0189, 0191, 0192, 0194, 0197, 0198, 0202, 0204, 0211, 0212, 0218, 0234,\n\n0235, 0236, 0237, 0238, 0239, 0240, 0241, 0242, 0243, 0244, 0245, 0246, 0248,\n\n0249, 0250, 0251, 0252, 0253, 0255, 0256, 0257, 0258, 0259, 0261, 0262, 0263,\n\n0264, 0265, 0266, 0267, 0269, 0270, 0271, 0272, 0273, 0274, 0275, 0276, 0277,\n\n0278, 0279, 0280, 0281, 0282, 0283, 0284, 0286, 0287, 0288, 0289, 0290, 0291,\n\n0292, 0293, 0294, 0295, 0296, 0297.\n\nIf one of the M/R grips listed above is installed, remove and replace with a serviceable part.\n\nNote: FAA AD 91-20-10 Amdt 39-8044 refers.\n\nCompliance: Within 50 hours time in service after 12 January 1992.\n\nBackground: The FAA has issued a Directive in response to reports that a vendor to BHTI produced and directly distributed 156 M/R grips which by-passed the FAA-approved quality control system. As a result, these M/R grips are potentially unsafe and must be removed from service. The effective date required by the FAA is extended by two months.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument remains narrowly focused on the original objective: identify and remove specific suspect main rotor grips that bypassed quality control. The only notable deviation from the FAA source is an extension of the FAA’s effective date by two months (Background), which alters timing but does not broaden the set of affected parts, aircraft, or required actions."},"complexity_factors":["Single-purpose airworthiness directive focused on one part (main rotor grip part 47-120-252-11).","Long lists of serial numbers across two blocks (over 150 serial numbers listed), increasing clerical complexity for operators.","Clear conditional logic: if serial number is in list → remove and replace (simple binary test).","Cross-reference to FAA AD 91-20-10 (external regulatory reference).","Fixed compliance window (50 hours TIS) and specific effective date — creates timing constraint but not complex compliance sequencing.","No nested exceptions, few defined terms, and a single inspection method (visual)."],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- It requires operators of certain Bell 47-series helicopters to visually inspect the main rotor grip (part number 47-120-252-11) and check its serial number. (Requirement)\n- If the grip has one of the listed serial numbers, the grip must be removed and replaced with a serviceable part. (Requirement)\n- The inspection and any required replacement must be done within 50 hours time in service after 12 January 1992. (Compliance)\n\n**Which aircraft and people are affected**\n\n- Affects Bell Helicopter Textron Model 47 variants listed in the Applicability block (for example 47G2, 47G3, 47J2, and related sub‑models). (Applicability)\n- Affects owners/operators and maintenance organisations responsible for those helicopters, and the maintenance personnel who will perform the visual inspection and replacement. Operators are the ones who pay for inspection and any replacement parts and labour.\n\n**Why it matters (stated purpose and immediate safety mechanism)**\n\n- Stated purpose: the FAA identified 156 main rotor grips that bypassed the approved quality control system and may be unsafe, so those grips must be removed from service. The Directive here enforces the removal for Australian-registered aircraft of the same models that have the suspect grips. (Background; Requirement)\n\n**Practical steps required of operators**\n\n- Locate the main rotor grip (part 47-120-252-11).\n- Visually check the grip’s serial number against the two lists in the Requirement section.\n- If the serial number appears in those lists, remove that grip and fit a serviceable (approved, airworthy) replacement.\n- Complete the work within 50 hours’ flying time from the effective date stated. (Compliance)\n\n**Costs, incentives and trade-offs**\n\n- Direct cost: owners/operators bear the cost of inspection (labour time) and replacement parts where the listed grips are installed. (Requirement; Compliance)\n- Time cost: aircraft may be out of service during replacement; earlier or urgent flights may need scheduling adjustments.\n- Supply risk: if many operators need replacement grips at once, short-term demand could raise prices or cause delays obtaining serviceable parts (the text does not say how many spares exist). This is an implementation risk tied to the concentrated need for a specific part. (Background; inferred supply effect)\n- Liability/incentive effects: the background identifies a vendor quality control failure. That creates an incentive for operators and maintenance organisations to verify part provenance and for manufacturers/suppliers to control distribution channels. (Background)\n\n**Compliance burden and implementation risks**\n\n- Administrative burden is limited to a visual serial-number check and, where necessary, removal and replacement of the part. The inspection method is visual, not destructive or instrumented, reducing inspection complexity. (Requirement)\n- Implementation risk includes locating serial numbers (which can be trivial or time‑consuming depending on access), and obtaining an approved replacement in a timely manner. The instrument itself does not create additional bureaucratic discretion — it prescribes a clear action when a listed serial number is found. (Requirement)\n\n**Effects on private enterprise and markets**\n\n- Operators: bear direct costs and short-term downtime risk. (Requirement; Compliance)\n- Independent maintenance providers: will perform the inspections and replacements; revenue for these services is likely to increase for the affected fleet while the directive is active.\n- Parts suppliers/manufacturer: may face reputational, logistical, and warranty/recall costs. The directive formalises removal of parts that bypassed quality control, potentially increasing demand for correctly manufactured grips. (Background)\n\n**Who decides and what changes in behaviour**\n\n- The regulator mandates the inspection and replacement; the owner/operator decides when to schedule the inspection and which approved replacement to fit. (Requirement; Compliance)\n- Behavioural change: operators will check serial numbers on main rotor grips and replace listed parts; maintenance organisations may tighten procedures for verifying part provenance to avoid future costly removals. (Requirement; Background)\n\n**Cross-reference and timing nuance**\n\n- The AD notes that FAA AD 91-20-10 (Amdt 39-8044) is the related FAA action. This instrument extends the FAA’s effective date by two months (Background). This is a timing adjustment rather than an expansion of which parts must be removed. (Background)\n\n**Bottom line (practical takeaway)**\n\n- If you operate one of the listed Bell 47 models and have main rotor grip part 47-120-252-11 installed, check the grip’s serial number against the lists in this instrument immediately. If the serial number is on the list, arrange removal and replacement within the stated 50 hours’ flying time. The regulator’s stated aim is to remove potentially unsafe grips that bypassed approved quality control. (Requirement; Compliance; Background)"},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific manufacturing defect in a specific helicopter part. The scope remains precisely limited to the identified faulty main rotor grips; there is no evidence of scope creep beyond the original safety purpose."},"complexity_factors":["Single, specific mechanical component targeted (main rotor grip)","Clear applicability test: specific helicopter models AND specific part number","Binary compliance requirement: visual inspection followed by remove-and-replace if serial number matches","Straightforward deadline: 50 hours time-in-service after fixed date","No nested exceptions, conditional logic, or cross-references to other legislation beyond a single FAA reference note","Serial number lists are long but mechanically simple to check"],"plain_english_summary":"This AD requires owners/operators of specified Bell 47G/47J helicopters fitted with main rotor grip P/N 47-120-252-11 to visually inspect the grip for listed serial numbers (over 100, beginning \"IT\"/\"ITM\") and remove-and-replace any affected grips with a serviceable part within 50 flight hours after 12 January 1992.  \n\nIt responds to an FAA finding that a supplier bypassed quality control on 156 grips that could fail in flight; CASA adopts that finding but allows Australian operators an extra two months to comply."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-47-98-main-rotor-grip","history":"/api/acts/ad-bell-47-98-main-rotor-grip/history","analysis":"/api/acts/ad-bell-47-98-main-rotor-grip/analysis","conflicts":"/api/acts/ad-bell-47-98-main-rotor-grip/conflicts","importantCases":"/api/acts/ad-bell-47-98-main-rotor-grip/important-cases","documents":"/api/acts/ad-bell-47-98-main-rotor-grip/documents"}}