{"id":"F2006B02597","name":"AD/B-2/25 - Tail Rotor Blade - Inspection","slug":"ad-b-2-25-tail-rotor-blade-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41874,"registerId":"commonwealth-F2006B02597-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B-2/25 - Tail Rotor Blade - Inspection","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)  \nBrantly B-2 Series Helicopters\n\nAD/B-2/25 Tail Rotor Blade \\- Inspection 1/66\n\nApplicability: All model B-2 series S/Nos. 454 and below.\n\nRequirement: 1. Remove and disassemble the tail rotor blade assembly P/N B2-111-11 from hub and thrust bearings in accordance with Brantly Model B2B Maintenance Manual.\n\n    2. Using letter sealing wax or any other hard setting low temperature melting (250oF or less) material, make an impression of the thrust bearing shoulder relief radius in the grip at blade station 3.06 and inspect for a radius less than 0.020 inches.\n\n    3. Using at least a two power magnifying glass, inspect for sharp circumferential tool marks deeper than 0.010 inches.\n\n    4. Remove from service any tail rotor blade with tool marks deeper than 0.010 inches or relief radius less than 0.020 inches, before further flight.\n\n    5. Reinstall any tail rotor blade with tool marks not deeper than 0.010 inches or relief radius not less than 0.020 inches in accordance with Brantly Model B2B Maintenance Manual; or\n\nFAA AD 65-28-1.\n\nCompliance: Forthwith.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted airworthiness directive addressing a specific manufacturing defect in a specific helicopter model. It has not expanded beyond its original safety purpose."},"complexity_factors":["Single, discrete safety directive with only 5 numbered requirements","No defined terms section — technical terms are industry standard (P/N, station numbers)","No cross-references to other legislation beyond optional FAA alternative","Clear binary compliance path: inspect → either remove or reinstall","Specific, measurable thresholds (0.020 inches, 0.010 inches, 2x magnification)","Limited applicability (specific aircraft model and serial number range)"],"plain_english_summary":"Owners/operators of Brantly B‑2 helicopters (serial numbers 454 and below) must immediately inspect tail rotor blades for manufacturing defects that could cause in‑flight failure. The AD requires disassembly, a sealing‑wax impression of the thrust bearing area, and magnified inspection for undersized radii or deep tool marks; any defective blade must be removed and the helicopter grounded.\n\nThis is mandatory \"forthwith\" action for safety; compliance may alternatively follow FAA AD 65‑28‑1."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive expressly applies to all Brantly B‑2 series helicopters with serial numbers 454 and below. The text does not indicate any expansion or narrowing of that applicability beyond the stated serial‑number range."},"complexity_factors":["Technical measurement thresholds for acceptance/rejection (radius 0.020 inches, tool‑mark depth 0.010 inches) increase precision demands","Physical removal, disassembly and reinstallation of tail rotor blade assemblies per Brantly Model B2B Maintenance Manual","Specific inspection technique required (low‑temperature hardening material impression and ≥2× magnification)","Immediate compliance timeframe: \"Forthwith\" creates scheduling and operational pressure","Clear go/no‑go criteria reduce discretionary judgement but increase replacement likelihood if limits are exceeded","External cross‑reference to FAA AD 65‑28‑1 introduces linkage to another regulatory instrument"],"plain_english_summary":"This airworthiness directive requires owners/operators of Brantly B‑2 helicopters (serial numbers 454 and below) to remove each tail‑rotor blade assembly, make a low‑temperature impression and visually inspect a specified shoulder relief radius and circumferential tool marks, and to remove from service any blade that fails the numeric limits. (Requirement paras 1–4.)\n\nThe cost and operational burden fall on owners/operators and maintenance staff for disassembly, inspection (wax impression and magnifier) and replacement where required; work must follow the Brantly Model B2B Maintenance Manual and be done forthwith. (Applicability; Requirement 5; Compliance.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection","history":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection/history","analysis":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection/analysis","conflicts":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection/conflicts","importantCases":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection/important-cases","documents":"/api/acts/ad-b-2-25-tail-rotor-blade-inspection/documents"}}