{"id":"F2006B10484","name":"AD/HS 125/45 Amdt 3 - Retirement Lives - Fatigue Critical Components","slug":"ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116231,"registerId":"commonwealth-F2006B10484-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/45 Amdt 3 - Retirement Lives - Fatigue Critical Components","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/HS 125/45 Amdt 2 and issues the following 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\nBritish Aerospace BAe 125 Series Aeroplanes\n\nAD/HS 125/45\n\nAmdt 3\n\n  \nRetirement Lives \\- Fatigue Critical Components 5/2003\n\nApplicability: All models.\n\nRequirement: All life limited items shall be retired from service at or before the times listed in the following documents, unless otherwise negotiated with the Authority.\n\n    a. \\-1/1A/1B Series: Hawker Raytheon Corporate Jets Maintenance Schedule \\- contained in the 125-1 Maintenance Library, Revision 1, issued June 2002.\n\n    b. \\-3/3A/3B/3A-R/3B-RA Series: Hawker Raytheon Corporate Jets Maintenance Schedule \\- contained in the 125-3 Maintenance Library, Revision 1, issued June 2002.\n\n    c. \\-400A/B Series: Hawker Raytheon Corporate Jets Maintenance Schedule, Revision 2, issued December 2001.\n\n    d. \\-600A/B Series: Hawker Raytheon Corporate Jets Maintenance Schedule, Revision 4, issued December 2002.\n    2. 700 Series: Hawker Raytheon Corporate Jets 125 series 700 Flexible Maintenance Schedule, Revision 2, issued December 2002.\n    3. 800 Series: Hawker Raytheon Corporate Jets 125 series 800 Flexible Maintenance Schedule, Revision 6, issued December 2002.\n\n    4. 1000 Series: Hawker Raytheon Corporate Jets 125 series 1000 Flexible Maintenance Schedule, Revision 4, issued June 2002. (The “High Utilisation” Maintenance Schedule for the 1000 series has now been deleted).\n\nNote 1: The service lives have been calculated by the manufacturer on the following basis (British Aerospace SB 51-2 refers):\n\nOne cabin pressurisation to maximum differential pressure, One full cycle of flap operation, and\n\nOne full landing gear cycle per flight.\n\nBritish Aerospace BAe 125 Series Aeroplanes\n\nAD/HS 125/45 Amdt 3 (continued)\n\nIn addition, it has been assumed that the cruise altitude for most flights is 20,000 ft or above. Should the pattern of aircraft operation differ significantly from these assumptions, operators are to advise the Authority, as it will be necessary to revise the fatigue lives quoted.\n\nNote 2: With few exceptions, the above documents list only those items having life limitations of 20,000 flights or less. The Authority must be advised immediately upon reaching 19,500 flights to enable the fatigue life of the aircraft beyond 20,000 flights to be assessed.\n\nCompliance: As per the documents referenced in the Requirement section of this Directive.\n\nThis Amendment becomes effective on 15 May 2003.\n\nBackground: This Amendment updates the Requirement section to reflect the latest revisions of the referenced documents.\n\nThe previous Amendment was raised to include the 1000 series aircraft and to reference the latest revision to the Maintenance Schedules.\n\nAmendment 2 of this Airworthiness Directive became effective on 20 July 1995. Amendment 1 of this Airworthiness Directive became effective on 31 October 1985.\n\nThe original issue of this Airworthiness Directive became effective on 31 March 1977.\n\n![](image.002.jpeg)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 20 March 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 23 April 2003.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Amendment 3 updates the Requirement section to reference the latest revisions of series‑specific Hawker Raytheon maintenance schedules and clarifies service‑life assumptions. It does not expand or narrow the AD's applicability (remains 'All models') but changes the controlling document versions and thus the specific retirement times operators must follow."},"complexity_factors":["Relies on multiple external maintenance documents with specific revision numbers — operators must obtain and apply those documents.","Different maintenance schedules apply by series (1/1A/1B, 3/3A/3B, 400, 600, 700, 800, 1000) creating administrative mapping and record‑keeping burden.","Service lives are calculated from operational assumptions (pressurisation, flap cycles, landing‑gear cycles, typical cruise altitude) — deviations require operator notification and possible reassessment.","Discretionary phrase 'unless otherwise negotiated with the Authority' permits case‑by‑case exceptions, introducing regulatory discretion and negotiation costs.","Mandatory notification at 19,500 flights for assessment beyond 20,000 flights imposes monitoring and reporting obligations.","Compliance timing is defined by referenced documents rather than explicit dates in the AD, which transfers interpretive work to operators and maintainers."],"plain_english_summary":"This Airworthiness Directive requires operators of all British Aerospace BAe 125 series aircraft to retire life‑limited, fatigue‑critical components at or before the times listed in the specified Hawker Raytheon maintenance schedules (series‑specific revisions). It revokes the prior amendment and makes compliance dependent on those referenced documents.\n\nOperators (owners/maintenance organisations) pay for replacements, may negotiate exceptions with the Authority, and must notify the Authority at 19,500 flights if the aircraft may exceed 20,000 flights. Fatigue lives are based on specified cycle and altitude assumptions."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"The legislation remains tightly scoped to its original purpose: establishing retirement lives for fatigue-critical components in BAe 125 aircraft. While Amendment 3 updates document references and removes the 'High Utilisation' schedule for the 1000 series, this represents normal maintenance of regulatory currency rather than scope creep. The original 1977 intent — preventing fatigue failures through mandatory component retirement — remains unchanged."},"complexity_factors":["Multiple document references (7 different maintenance schedules for different aircraft sub-models)","Cross-referencing to external manufacturer documents not reproduced in the directive itself","Conditional compliance based on operational patterns (the 'significantly different' operations clause)","Nested notification requirement (19,500 flight trigger point creates a secondary assessment process)","Implicit incorporation by reference of British Aerospace Service Bulletin 51-2","Historical amendment layering (3rd amendment since 1977, with effective dates scattered throughout text)"],"plain_english_summary":"This CASA safety directive imposes mandatory retirement deadlines for fatigue‑critical components on BAe 125 series business jets, requiring owners, operators and maintenance organisations to replace life‑limited parts at or before the hours/cycles in the applicable manufacturer maintenance manuals. Most limits are ≤20,000 flights; operators must notify CASA at 19,500 flights so remaining safe life can be assessed. Different operating profiles (short hops, low altitude) may require recalculated limits. The rule prevents catastrophic fatigue failures."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components","history":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components/history","analysis":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components/analysis","conflicts":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components/conflicts","importantCases":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components/important-cases","documents":"/api/acts/ad-hs-125-45-amdt-3-retirement-lives-fatigue-critical-components/documents"}}