{"id":"F2006B08558","name":"AD/CHA/5 - Lower Fuselage Longerons","slug":"ad-cha-5-lower-fuselage-longerons","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51366,"registerId":"commonwealth-F2006B08558-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CHA/5 - Lower Fuselage Longerons","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  American Champion (Aeronca, Bellanca) Series Aeroplanes\n\n \n\nAD/CHA/5 Lower Fuselage Longerons 11/71\n\nApplicability: Model 7ECA, 7GCAA, 7GCBC and 7KCAB. Requirement:  Action in accordance with Champion SL No. 96. Compliance:               Within 100 hours time in service after 30 November 1971.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD, as written, applies to the listed aircraft models and requires the actions described in Champion SL No. 96 within a specified 100-hour compliance window after 30 November 1971. The text contains no amendment, extension, or qualification that would indicate a change from that stated scope."},"complexity_factors":["Narrow and specific applicability (only four model variants listed) reduces scope complexity (Applicability).","Reference to an external technical document (Champion SL No. 96) increases implementation complexity because the AD does not contain the technical steps (Requirement).","A fixed compliance window tied to a historical date and flight hours requires operators to convert operational hours into scheduling actions (Compliance).","Lack of technical detail in the AD increases reliance on maintenance organisations and the service letter, adding administrative steps and possible ambiguity (Requirement).","Enforcement is regulatory and binary (must comply), but technical discretion lies with the service letter and maintenance providers, creating split responsibilities between regulator and manufacturer (Requirement)."],"plain_english_summary":"This AD mandates owners/operators of certain American Champion (Aeronca/Bellanca) models (7ECA, 7GCAA, 7GCBC, 7KCAB) to carry out the corrective work described in Champion Service Letter No. 96 on the lower fuselage longerons within 100 hours TIS after 30 November 1971.  \n\nIt enforces a manufacturer-prescribed structural remedy for safety, placing compliance, parts, labour and downtime costs on aircraft owners/operators and their maintenance providers."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive from 1971 targeting a specific structural defect in specific aircraft models. It has not expanded beyond its original narrow technical purpose."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory text","Single, unambiguous compliance requirement with clear deadline","No defined terms section — relies on external reference to Champion Service Letter No. 96 for technical details","No nested exceptions, conditional logic, or cross-references to other legislation","Applicability limited to 4 specific aircraft models by name"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific American Champion aeroplane models (the 7ECA, 7GCAA, 7GCBC, and 7KCAB) to inspect or repair the **lower fuselage longerons** (structural metal supports running along the bottom of the aircraft body) according to Champion Service Letter No. 96.\n\n**Who it affects:** Anyone who owns, operates, or maintains these four specific models of American Champion aircraft (previously manufactured under the Aeronca and Bellanca names).\n\n**What they must do:** Complete the required inspection or repair work within 100 hours of flying time after 30 November 1971.\n\n**Why it matters:** This directive addresses a potential structural weakness that could compromise airframe integrity and flight safety. Non-compliance means the aircraft cannot legally fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cha-5-lower-fuselage-longerons","history":"/api/acts/ad-cha-5-lower-fuselage-longerons/history","analysis":"/api/acts/ad-cha-5-lower-fuselage-longerons/analysis","conflicts":"/api/acts/ad-cha-5-lower-fuselage-longerons/conflicts","importantCases":"/api/acts/ad-cha-5-lower-fuselage-longerons/important-cases","documents":"/api/acts/ad-cha-5-lower-fuselage-longerons/documents"}}