{"id":"F2006B10738","name":"AD/HU 369/73 - Tail Rotor Fork Bolt","slug":"ad-hu-369-73-tail-rotor-fork-bolt","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116736,"registerId":"commonwealth-F2006B10738-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 369/73 - Tail Rotor Fork Bolt","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 369/73 Tail Rotor Fork Bolt 3/88 DM\n\nApplicability: All model 369 series helicopters with P/N 369A 1602 tail rotor fork bolts installed. Requirement: Action in accordance with McDonnell Douglas SIN No. HN-212, DN-153, EN-43,\n\nFN-32, as applicable.\n\nCompliance: a. For Part I of Requirement document; within 25 hours time in service after 31 January 1988.\n\nb. For Part II of Requirement document; at the next 300 hour or annual inspection, or at the next disassembly of the tail rotor assembly; whichever occurs first.\n\nc. For Part I of Requirement document; all tail rotor fork bolts and tail rotor assemblies in spares inventories prior to being installed on helicopters.\n\nBackground: MDHC has determined that a possibility exists that some P/N 369A 1602 tail rotor fork bolts did not receive proper processing at the manufacturer. Inadequate processing of these bolts can result in cracking and eventual bolt failure.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1709},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This directive maintains its original targeted scope—addressing a specific manufacturing defect in a critical helicopter component. There is no evidence of scope expansion beyond the original safety purpose of preventing tail rotor fork bolt failure."},"complexity_factors":["Multiple conditional compliance deadlines based on four different triggers (flight hours accumulated, calendar dates, scheduled maintenance intervals, or physical disassembly)","Cross-references to four separate manufacturer Service Information Notice documents (HN-212, DN-153, EN-43, FN-32)","Technical aviation terminology requiring specialized knowledge to interpret (part numbers, time in service, airworthiness concepts)","Specific applicability limited to precise part numbers requiring verification against aircraft records"],"plain_english_summary":"Operators of McDonnell Douglas (Hughes) and Kawasaki 369-series helicopters with tail rotor fork bolt P/N 369A 1602 must perform urgent maintenance per the manufacturer’s service instructions and inspect spare-bolt inventory before installation. The directive imposes near-term inspection and replacement deadlines to address bolts that may lack proper treatment and can crack. Failure of a tail rotor fork bolt risks loss of tail rotor function and potential loss of control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt","history":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt/history","analysis":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt/analysis","conflicts":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt/conflicts","importantCases":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt/important-cases","documents":"/api/acts/ad-hu-369-73-tail-rotor-fork-bolt/documents"}}