{"id":"F2006B05025","name":"AD/CESSNA 177/30 Amdt 1 - Wing Main Spar Carry-Through Section","slug":"ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44935,"registerId":"commonwealth-F2006B05025-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 177/30 Amdt 1 - Wing Main Spar Carry-Through Section","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)  Cessna 177 Series Aeroplanes\n\n \n\n# AD/CESSNA 177/30\n\nAmdt 1\n\nApplicability: All models.\n\n# Wing Main Spar Carry-Through Section 10/90\n\n \n\nRequirement: 1. Gain access to the upper and lower surfaces of the wing carry through forging.\n\n \n\n2.    Inspect the whole wing carry-through forging for any indications of corrosion. Repairs to the wing carry- through forging shall be in accordance with Schemes approved by the Authority.\n\n \n\nCompliance: Unless already accomplished in accordance with the initial issue of this Directive:\n\n \n\n1. For aircraft over ten years time in service since date of manufacture: forthwith, and\n\n\n \n\nb.   For aircraft with less than ten years time in service since date of manufacture: before attaining ten years time in service, and\n\n \n\nc.    For all aircraft after initial inspection:\n\n \n\ni)     at periods not exceeding six years time in service, or\n\n \n\nii)  where the spar carry-through has been subjected to an approved corrosion protection scheme: at periods not exceeding twelve years.\n\n \n\nBackground: There have been reports of corrosion in the wing spar carry-through forging on a number of aircraft. In two cases the corrosion was sufficiently advanced to adversely affect the structural integrity of the wing. Amendment 1 reflects the reported results from the initial issue of this Directive. This has enabled a reduction in the initial compliance time and an extension of the repeat inspection period.\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_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 maintenance directive that has remained focused on its original purpose: ensuring the structural integrity of Cessna 177 wing spar carry-through sections. Amendment 1 refined the inspection intervals based on operational data but did not expand the scope beyond corrosion inspection of this specific component."},"complexity_factors":["Very short document (approximately 250 words)","Only 1 defined term implicitly used ('time in service' — standard aviation term)","Simple conditional structure based solely on aircraft age","No cross-references to other legislation or regulations","Single requirement with clear compliance deadlines","Plain language background explanation included"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of Cessna 177 Cardinals in Australia to inspect the wing main spar carry‑through forging for corrosion and repair using CASA‑approved methods. Older aircraft must be inspected immediately; newer ones before they hit 10 years, with repeat inspections every 6 years (or 12 years if an approved anti‑corrosion treatment is applied).\n\nThe rule addresses dangerous wing‑attach structural corrosion; Amendment 1 lengthened allowable repeat intervals based on inspection data."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 1 alters timing: it reduces the initial compliance time for some aircraft and extends the repeat inspection period (background notes this change). The Directive's applicability to all Cessna 177 models and the substantive requirement to inspect and repair the spar forging remain unchanged; the key change is the timing of initial and recurrent inspections and the conditional longer interval where an approved corrosion‑protection scheme is used."},"complexity_factors":["Technical inspection requirement: access to upper and lower surfaces of the spar carry‑through forging likely requires disassembly or significant maintenance work.","Age‑based compliance schedule: differing initial compliance deadlines for aircraft over or under ten years in service.","Variable recurring intervals: general repeat inspections every 6 years, extended to 12 years only where an approved corrosion protection scheme has been applied.","Repair approvals: repairs must follow schemes approved by the Authority, introducing regulatory discretion and an approval process.","Limited procedural detail: the Directive mandates inspection and repairs but does not specify inspection methods, acceptance criteria, or detailed repair standards.","Applicability: applies to all Cessna 177 models, so it creates uniform obligations across an entire fleet."],"plain_english_summary":"This airworthiness directive requires owners/operators of all Cessna 177 models to open up and inspect the wing main-spar carry‑through forging (upper and lower surfaces) for corrosion, and to carry out any repairs only under Civil Aviation Safety Authority (CASA)‑approved repair schemes. It sets age‑based initial inspection timing and recurring inspection intervals, with longer intervals allowed where an approved corrosion‑protection scheme has been applied. Owners/operators pay for inspections and repairs; CASA approves repair schemes. The measure responds to reported corrosion that has in some cases affected wing structural integrity."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section","history":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section/history","analysis":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section/analysis","conflicts":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section/conflicts","importantCases":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section/important-cases","documents":"/api/acts/ad-cessna-177-30-amdt-1-wing-main-spar-carry-through-section/documents"}}