{"id":"F2006B10672","name":"AD/HU 369/112 - Main Rotor Drive Shaft","slug":"ad-hu-369-112-main-rotor-drive-shaft","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116608,"registerId":"commonwealth-F2006B10672-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 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\n![](image.001.png)  \n\nMcDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters","sortOrder":0},{"sectionNumber":"AD/HU 369/112 Main Rotor Drive Shaft 11/","sectionType":"part","heading":"AD/HU 369/112 Main Rotor Drive Shaft 11/2003","content":"# AD/HU 369/112 Main Rotor Drive Shaft 11/2003\n\nApplicability: Model 600N, fitted with main rotor drive shaft assembly, part number (P/N) 600N5510-1.\n\nRequirement: 1. Unless previously accomplished revise the component history card or equivalent record for drive shaft, P/N 600N5510-1, by changing the life limit from 16,000 to 14,000 hours time in service (TIS).\n\n2. Replace any drive shaft that has 14,000 or more hours TIS with an airworthy drive shaft\n\nNote: FAA AD 2003-16-11 Amdt 39-13264 refers.\n\nCompliance: For Requirement 1: Within 100 flight hours from the effective date of this Directive.\n\nFor Requirement 2: Before further flight, following the completion of Requirement 1 of this Directive.\n\nThis Airworthiness Directive becomes effective on 30 October 2003.\n\nBackground: A review of final fatigue test data indicates that the life limit of the drive shaft should be reduced by 2000 hours time-in-service (TIS). The actions specified by this AD are intended to prevent failure of the drive shaft, loss of drive of the main rotor system, and subsequent loss of control of the helicopter.\n\n![](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 18 September 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 8 October 2003.","sortOrder":1}],"analysis":{"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 standard airworthiness directive with narrow, targeted scope. It addresses a specific safety-critical component on a specific helicopter model. There is no indication of scope creep; the directive precisely matches its stated purpose of preventing drive shaft failure."},"complexity_factors":["Single, clearly identified aircraft model and part number","Only two straightforward requirements with explicit deadlines","No defined terms section or complex interpretation provisions","No nested exceptions or conditional logic — requirements apply universally to affected aircraft","Minimal cross-referencing (only a note to related FAA directive)","Short document (approximately 250 words) with clear structure: Applicability, Requirement, Compliance, Background"],"plain_english_summary":"This safety order shortens the life limit of the main rotor drive shaft (P/N 600N5510-1) on McDonnell Douglas (Hughes)/Kawasaki 369 Series Model 600N helicopters from 16,000 to 14,000 flight hours. Owners, operators, and maintenance organizations must update records within 100 flight hours and replace any shaft already at or above 14,000 hours before further flight. It prevents catastrophic failure from unexpected fatigue."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The AD reduces the service life limit of the specified main rotor drive shaft by 2,000 hours (from 16,000 to 14,000 TIS), requires updating component history records, and mandates replacement of any shaft with 14,000 or more hours before further flight. Deadlines: record revision within 100 flight hours and immediate replacement before next flight (Applicability; Requirement; Compliance; Background)."},"complexity_factors":["Narrow applicability: applies only to Model 600N fitted with drive shaft P/N 600N5510-1 (Applicability)","Simple, discrete actions: revise record life limit and replace shafts at/above new limit (Requirement 1–2)","Clear deadlines: 100 flight hours for record update; replacement required before further flight (Compliance)","Safety-critical outcome increases urgency but not procedural complexity (Background)","Operational impact depends on inventory and logistics for replacement parts (implicit in Requirement 2)","Reliance on accurate times-in-service tracking for enforcement and compliance"],"plain_english_summary":"This AD shortens the life limit for main rotor drive shaft P/N 600N5510-1 on Model 600N helicopters from 16,000 to 14,000 flight hours and requires operators to update the component history and replace any shaft with 14,000 or more hours before further flight. (Applicability; Requirement). CASA (delegate under CASR subreg. 39.1(1)) sets 100 flight hours to revise records and mandates replacement before next flight; the stated goal is to prevent shaft failure and loss of control (Background). Owners/operators bear replacement and downtime costs and must keep accurate TIS records."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft","history":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft/history","analysis":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft/analysis","conflicts":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft/conflicts","importantCases":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft/important-cases","documents":"/api/acts/ad-hu-369-112-main-rotor-drive-shaft/documents"}}