{"id":"F2006B04821","name":"AD/CA21/2 - Wing Lift Struts","slug":"ad-ca21-2-wing-lift-struts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44621,"registerId":"commonwealth-F2006B04821-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CA21/2 - Wing Lift Struts","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)  Skyfox Aviation (Calair/Hedaro) CA21 and CA22A Series Aeroplanes\n\n \n\nAD/CA21/2 Wing Lift Struts 1/96\n\nApplicability: Aircraft with serial numbers CA-21004 to CA-21039 and CA-22001 to CA-22014.\n\n \n\nRequirement: Inspect the wing lift strut tube to fairing join for evidence of corrosion in accordance with Skyfox Aviation Service Bulletin No. 13.\n\n \n\nCompliance: Before further flight after 4 January 1996.\n\n \n\nBackground: It has been reported that corrosion can initiate at the tube to fairing join. This AD requires removal of the fairings if corrosion is found and possible replacement of the strut tube.\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":2,"scope_assessment":{"changed":false,"description":"The AD applies only to the listed serial-numbered CA21/CA22A aeroplanes and mandates inspection and remedial action for corrosion at the tube-to-fairing join. The instrument does not expand the affected fleet or add unrelated obligations beyond inspection and repair procedures referenced to the Service Bulletin; therefore the scope remains as set out in the directive (Applicability; Requirement; Background)."},"complexity_factors":["Narrow applicability limited to specific serial-number ranges (Applicability)","Single, clearly stated required action (inspect) with a referenced Service Bulletin for procedure (Requirement)","Immediate compliance deadline (before further flight after 4 January 1996) increases operational urgency but not legal ambiguity (Compliance)","Possible contingent repair actions (fairing removal and possible strut-tube replacement) introduce logistical/parts considerations but not legal complexity (Background)"],"plain_english_summary":"This AD mandates immediate inspection of the wing lift strut tube-to-fairing join for corrosion on Skyfox CA21/CA22A aeroplanes with specified serial numbers, to be completed before further flight after 4 January 1996.  \n\nIf corrosion is found, fairings must be removed and the strut tube may need replacement. Owners/operators bear the inspection and repair costs and aircraft cannot fly until the AD’s requirements are met."},"kimi_summary":{"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific corrosion issue in specific aircraft serial numbers. It has not expanded beyond its original purpose of mandating an inspection for a known safety defect."},"complexity_factors":["Single, specific mechanical component addressed (wing lift strut tube to fairing join)","No defined terms section","No cross-references to other legislation (only references a Service Bulletin)","Simple binary compliance requirement (inspect before flying)","No conditional logic or exceptions","Extremely short document (approximately 150 words of substantive content)"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by the Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:** It orders owners and operators of certain Skyfox Aviation CA21 and CA22A series aeroplanes to inspect a specific part of the wing (the \"wing lift strut tube to fairing join\") for corrosion. If corrosion is found, the fairing must be removed and the strut tube may need replacement.\n\n**Who it affects:** Owners and operators of Skyfox Aviation aircraft with serial numbers CA-21004 through CA-21039 and CA-22001 through CA-22014.\n\n**Why it matters:** Corrosion at this joint could weaken the wing structure, potentially leading to structural failure. The directive was issued after reports showed this corrosion could start at the tube-to-fairing connection. Compliance is mandatory \"before further flight\" after 4 January 1996 — meaning no flying until the inspection is done."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ca21-2-wing-lift-struts","history":"/api/acts/ad-ca21-2-wing-lift-struts/history","analysis":"/api/acts/ad-ca21-2-wing-lift-struts/analysis","conflicts":"/api/acts/ad-ca21-2-wing-lift-struts/conflicts","importantCases":"/api/acts/ad-ca21-2-wing-lift-struts/important-cases","documents":"/api/acts/ad-ca21-2-wing-lift-struts/documents"}}