{"id":"F2006B08883","name":"AD/DH 104/5 Amdt 6 - Wing and Centre Section Lower Spar Booms - Safe Lives","slug":"ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52359,"registerId":"commonwealth-F2006B08883-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH 104/5 Amdt 6 - Wing and Centre Section Lower Spar Booms - Safe Lives","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)  \nDH 104 (Dove) Series Aeroplanes\n\nAD/DH 104/5\n\nAmdt 6\n\nApplicability: All models.\n\n  \n\nWing and Centre Section Lower Spar Booms - Safe Lives\n\n  \n7/75\n\nRequirement: 1. The retirement lives shall be in accordance with the Hawker Siddeley Technical News Sheet CT (104) No. 119, Issue 10, and CT (104) No. 181 Issue 2 as applicable, with the following exceptions:\n\n    2. The wing safe lives shall be as follows:\n\n    (a) Aircraft Series 1 to 6 and variants \\- 17,500 hours total time in service. (Para.\n    4.3.1 of TNS 119).\n\n    (b) Aircraft Series 7 and 8 and variants \\- 14,000 hours total time in service. (Para.\n    4.3.2 of TNS 119).\n\n    (c) Aircraft Series 7XC and 8XC - 14,000 hours total time in service plus one fifth of the number of hours flown prior to conversion (Para. 7 of TNS 181).\n\n    (d) Any DOVE aircraft series 1 to 6 which have been converted to DH 104 Riley Dove in accordance with STC SA319SO - 17,500 hours total time in service.\n\n    3. The secretary shall be notified if, in accordance with para. 3.2 of Technical News Sheet No. 119, severe flight conditions necessitating individual life assessment as identified.\n\n    4. Paragraphs 4.1, 512 and 5.3 of Technical News sheet No. 119 specify retirement lives lying between upper and lower limits. The lower number of hours will apply in each case unless, in accordance with paragraph 6 of the Technical New Sheet, the operator can obtain from the manufacturer and forward to the Secretary an overriding safe life assessment for his individual aircraft.\n\nNote: The Riley Dove safe life of Para. 2(d) has been based on fatigue meter records provided to the Department, and may be subject to review should further operational experience show this to be necessary.\n\nCompliance: As detailed in the requirement document.","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"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This appears to be Amendment 6 of an existing Airworthiness Directive (AD/DH 104/5), which maintains the original scope of regulating fatigue life limits for DH 104 Dove wing spar structures. The amendment appears to update the safe life hours and incorporate additional variants (particularly the Riley Dove conversion in paragraph 2(d)), but does not expand beyond the original purpose of ensuring structural integrity of these specific aircraft components."},"complexity_factors":["Multiple cross-references to external technical documents (Hawker Siddeley Technical News Sheets CT (104) No. 119 Issue 10 and CT (104) No. 181 Issue 2) that are not reproduced in the directive itself","Four separate safe life calculations depending on aircraft series and conversion status (Series 1-6, 7-8, 7XC/8XC with conversion hours formula, and Riley Dove STC conversion)","Conditional logic allowing operators to seek individual overriding assessments from the manufacturer (paragraph 6 exception)","Mandatory notification requirement triggered by subjective assessment of 'severe flight conditions'","Nested structure: main requirement references TNS 119, but then lists exceptions to that document, plus a note indicating potential future review of the Riley Dove limit","Use of technical aviation terminology without definition (spar booms, STC, TNS, total time in service)"],"plain_english_summary":"This Airworthiness Directive mandates “safe life” retirement limits for the wing and centre‑section lower spar booms of de Havilland DH‑104 Dove aircraft, requiring parts be removed and replaced after their specified flight‑hour lives (roughly 14,000–17,500 hours depending on series). \n\nIt applies to owners, operators and maintenance organisations, requires tracking hours and reporting severe flight conditions, and lets operators seek individual assessments to justify alternate limits — all to prevent fatigue‑related structural failure."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This AD specifies fixed retirement lives and conversion rules for DH 104 series that modify/override the guidance in Hawker Siddeley Technical News Sheets (TNS 119 and TNS 181), adds a notification requirement for severe-flight-condition assessments, and permits manufacturer-issued overriding safe-life assessments (Requirement 1; Paras. 2–4)."},"complexity_factors":["Different retirement-hour thresholds for multiple aircraft series (Para. 2(a)–(c))","Conversion-specific rule that adds one-fifth of pre-conversion hours for series 7XC/8XC (Para. 2(c))","Special rule for Riley Dove conversions under STC SA319SO (Para. 2(d))","Relies on external Technical News Sheets (TNS 119 and TNS 181) but overrides or modifies some of their provisions (Requirement 1; Para. 4)","Operator obligation to notify the Secretary when severe flight conditions require individual life assessment (Para. 3)","Process allowing manufacturer-provided overriding safe-life assessments for individual aircraft, introducing discretionary technical approval (Para. 4)","Note that the Riley Dove safe life may be reviewed with further operational data, creating potential future change (Note)"],"plain_english_summary":"This airworthiness directive sets mandatory retirement hours for the wing and centre‑section lower spar booms of DH 104 (Dove) aeroplanes, applies to all models, and requires operators to notify the Secretary if severe flight conditions trigger individual assessments. It replaces some provisions of Hawker Siddeley Technical News Sheets by prescribing fixed total‑time limits and allows manufacturer‑issued overriding safe‑life assessments."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives","history":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives/history","analysis":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives/analysis","conflicts":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives/conflicts","importantCases":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives/important-cases","documents":"/api/acts/ad-dh-104-5-amdt-6-wing-and-centre-section-lower-spar-booms-safe-lives/documents"}}