{"id":"F2006B10726","name":"AD/HU 369/62 Amdt 4 - Tail Rotor Blade Abrasion Strip","slug":"ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116713,"registerId":"commonwealth-F2006B10726-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 369/62 Amdt 4 - Tail Rotor Blade Abrasion Strip","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)  \nMcDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters\n\nAD/HU 369/62\n\nAmdt 4\n\n  \nTail Rotor Blade Abrasion Strip 12/94\n\nApplicability: 1. All 369 Series helicopters equipped with the tail rotor blade part numbers listed in McDonnell Douglas SIN HN-232, DN-179, EN-70, or FN-57, or\n\n    2. Installed after production P/N 369A1613-3M, and\n\n    3. Any of the SIN listed P/N with a suffix such as the letters M or M-STC added to the dash numbers after production.\n\nRequirement: 1. Visually check each tail rotor blade abrasion strip for evidence of bond failure along the entire abrasion strip/airfoil bond line. If this check results in suspect areas, inspect in accordance with Part I of McDonnell Douglas SIN HN-232, DN- 179, EN-70, or FN-57, as applicable.\n\nNote: MDHC SIN HN-197.2, DN-130.2, EN-19.2, and FN-17.1 dated 23 March 1987\n\ncontains additional information on checks and inspections.\n\n2. Unless already accomplished inspect in accordance with Part I of McDonnell Douglas SIN HN-232, DN-179, EN-70, or FN-57, as applicable and, if no debonding exists, install tail rotor blade abrasion strip rivets in accordance with Part II of McDonnell Douglas SIN No HN-232, DN-179, EN-70, or FN-57, as applicable.\n\nNote: FAA AD 94-18-08 refers.\n\nCompliance: 1. At each Daily Inspection until two rivets are installed.\n\n2. Within 25 hours time in service, or seven days after 23 October 1992, whichever occurs first.\n\nThis amendment is effective from 10 November 1994.\n\nNote: This Directive shall be entered on the Maintenance Release as maintenance required. The visual inspection required by Para 1 may be performed by the pilot in command in which case certification is to be made by entering AD/HU 369/62 Amdt 4 against the Daily Inspection certification of the Maintenance Release. A copy of this Airworthiness Directive is to be kept in the aircraft.\n\nBackground: Separation of the abrasion strip epoxy bond has been experienced.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nThe revised Requirement Documents in Amendment 1 included additional blade part numbers, and additional serial numbers for the previously affected part number blades. Amendment 2 was raised to align this Directive with the recently issued Country of Origin AD which requires repetitive inspections followed with a terminating modification action. Amendment 3 is the result of a FAA priority AD raised as the result of an accident from abrasion strip and subsequent tail rotor separation, despite the daily inspection. It also contains additional applicable part numbers. Amendment 4 updates the FAA AD reference which supersedes FAA Priority Letter 92-22-14 and FAA AD 92-02-15. No further work is required as a result of this amendment.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Scope expanded through amendments: additional blade part numbers and serial numbers were added (Amendment 1 and 3), the directive was aligned with the Country of Origin/FAA AD to require repetitive inspections followed by a terminating modification (Amendment 2), and FAA references were updated (Amendment 4)."},"complexity_factors":["Multiple affected part numbers and suffix variants (SIN HN-232, DN-179, EN-70, FN-57 and suffixes) increasing applicability scope.","Requirement cross-references external manufacturer Service Instruction Notices (Part I and II of respective SINs) for inspection and rivet installation procedures.","Layered compliance timing: daily inspections until rivets fitted plus a fixed compliance window (25 hours TIS or seven days from 23 October 1992).","Record-keeping and certification obligations: entry on the Maintenance Release and retaining a copy of the AD; pilot may perform the visual check but certification remains required.","History of amendments aligning with Country of Origin/FAA ADs (adds serial numbers, repetitive inspections, terminating modification), creating interlocking regulatory references."],"plain_english_summary":"This Airworthiness Directive tells operators of McDonnell Douglas (Hughes) and Kawasaki 369‑series helicopters with certain tail‑rotor blade part numbers to visually inspect the abrasion‑strip bond, follow the manufacturer's inspection procedure if problems are suspected, and fit rivets where no debonding exists. It mandates daily checks until rivets are installed and a compliance deadline of 25 flight hours or seven days from 23 October 1992. The action addresses reported separation of the abrasion‑strip epoxy bond."},"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":3,"scope_assessment":{"changed":true,"description":"Originally a simple inspection directive, this instrument has expanded significantly through four amendments. Amendment 1 added blade part numbers and serial numbers. Amendment 2 introduced a repetitive inspection regime with terminating modification. Amendment 3 expanded coverage again following a fatal accident and added more part numbers. Amendment 4 updated FAA references. The instrument has evolved from a basic safety notice into a comprehensive airworthiness regime covering an expanding fleet, though Amendment 4 itself makes no substantive changes to requirements."},"complexity_factors":["Multiple cross-references to manufacturer Service Information Notices (SINs) without reproducing their content—operators must locate HN-232, DN-179, EN-70, or FN-57 externally","Layered applicability criteria combining aircraft series, specific part numbers, production status, and suffix variations","Dual compliance pathways: repetitive daily inspections until a terminating action (rivet installation) is completed","Conditional logic: 'if suspect areas,' 'unless already accomplished,' 'if no debonding exists'","Multiple effective dates and amendment history creating a trail of superseded requirements"],"plain_english_summary":"This safety directive requires owners/operators of certain McDonnell Douglas (Hughes) and Kawasaki 369 Series helicopters to inspect tail-rotor abrasion strips after reports of epoxy bond failures that allowed strips to separate and once led to a rotor loss. It covers specified blade part numbers, including post-production or modified blades.\n\nPilots/mechanics must perform daily visual checks until mechanics install rivets to mechanically secure the strips—required within 25 flight hours or 7 days—to prevent catastrophic loss of control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip","history":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip/history","analysis":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip/analysis","conflicts":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip/conflicts","importantCases":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip/important-cases","documents":"/api/acts/ad-hu-369-62-amdt-4-tail-rotor-blade-abrasion-strip/documents"}}