{"id":"F2006B08807","name":"AD/DC3/31 Amdt 2 - Undercarriage Y Brace Fitting - Inspection","slug":"ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52181,"registerId":"commonwealth-F2006B08807-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DC3/31 Amdt 2 - Undercarriage Y Brace Fitting - Inspection","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)  \nDouglas DC3 Series Aeroplanes\n\nAD/DC3/31\n\nAmdt 2\n\n  \nUndercarriage “Y” Brace Fitting \\- Inspection 3/84\n\nApplicability: All models.\n\nRequirement: 1. Remove “Y” brace rear attachment fitting from the wing centre section (all part numbers).\n\n    2. Inspect fitting for cracks using an approved dye penetrant technique.\n\n    3. Inspect fitting for corrosion and elongation or enlargement of attachment holes.\n\nCompliance: Within 5000 hours time in service or 5 years, whichever occurs first, since last removal and inspection and thereafter at intervals not exceeding 5000 hours time in service or 5 years, whichever occurs first.\n\nBackground: This Directive is raised in issue to include all part number fittings due to reports of loose fittings and enlargement of attachment holes. Compliance requirements are amended to match the maximum time in service for wing removal and to ensure fitting removal at an acceptable calendar period for aircraft having a low annual utilization. Operators may wish to modify the centre section lower skin to facilitate fitting removal without wing removal.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Scope was expanded to include all part number fittings and the compliance timing was amended to match the maximum time in service for wing removal and to ensure a set calendar period for low‑utilisation aircraft (Background). The directive also notes an operator option to modify the centre‑section lower skin to facilitate removal without wing removal (Background)."},"complexity_factors":["Technical inspection standard: requires an approved dye‑penetrant technique (Requirement 2) — needs qualified personnel and equipment.","Removal requirement: fitting must be removed from wing centre section (Requirement 1) — may require wing removal unless the operator modifies centre‑section skin (Background).","Dual interval metric: recurring compliance set as 5,000 flight hours OR 5 years (Compliance) — tracking both time and hours increases administrative bookkeeping.","Broad applicability: applies to all models and all part numbers (Applicability; Background) — increases number of affected components and inventory/workflow impact.","Potential operational cost: removal/inspection frequency tied to maintenance cycles (Compliance) — increases labour, downtime and parts-handling costs for operators.","Discretion/opportunity: operators may choose a structural modification to avoid wing removal (Background) — introduces capital expenditure trade‑off and procedural variation between operators."],"plain_english_summary":"Requires removal and inspection of the DC‑3 undercarriage “Y”‑brace rear attachment fitting for cracks, corrosion and enlargement/elongation of attachment holes using an approved dye‑penetrant technique, at intervals of 5,000 flight hours or 5 years (whichever occurs first). It applies to all models and all part numbers.\n\nThe amendment expands coverage after reports of loose fittings and adjusts inspection timing to match wing‑removal cycles; operators are told they may modify the centre‑section lower skin to permit removal without full wing removal."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 2 to an existing directive. The scope has expanded slightly from the original by including \"all part number fittings\" rather than specific part numbers, but this remains within the original safety purpose of inspecting the Y brace fitting. The change reflects operational experience (reports of loose fittings) rather than mission creep."},"complexity_factors":["Single, discrete maintenance task with clear steps","Only 3 specific inspection requirements","Simple compliance formula: 5000 hours OR 5 years, whichever first","No cross-references to other legislation or regulations beyond the enabling authority (Civil Aviation Regulations 1998)","No defined terms section","Single applicability clause covering all models","Background section provides plain-language rationale"],"plain_english_summary":"This airworthiness directive requires all Douglas DC‑3 operators to remove and inspect the wing centre “Y brace rear attachment fitting” for cracks, corrosion, and enlarged bolt holes. Inspections must occur every 5,000 flight hours or 5 years (whichever comes first) and repeat on that schedule. The AD expands coverage to all part numbers and ensures low‑use aircraft aren’t left uninspected, addressing reports of loose fittings that could compromise structural integrity."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection","history":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection/history","analysis":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection/analysis","conflicts":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection/conflicts","importantCases":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection/important-cases","documents":"/api/acts/ad-dc3-31-amdt-2-undercarriage-y-brace-fitting-inspection/documents"}}