{"id":"F2006B02199","name":"AD/AC-CLA/6 - Wing Struts Carry-Through Tube","slug":"ad-ac-cla-6-wing-struts-carry-through-tube","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41429,"registerId":"commonwealth-F2006B02199-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AC-CLA/6 - Wing Struts Carry-Through Tube","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)  \nAircraft Parts and Development (CALL AIR) A-9 Series Aeroplanes\n\nAD/AC-CLA/6 Wing Struts Carry-Through Tube 3/79\n\nApplicability: All models A-9, A-9A and A-9B with wing struts carry through tube running through hopper.\n\nRequirement: To prevent failure of the main carry-through tube perform the following:\n\n    Remove the hopper top and inspect for a fibreglass wrapped carry-through tube. The main carry through tube if located in the hopper is located 625 mm aft of the hopper forward bulkhead and 150 mm below hopper surface. Visually inspect fibreglass wrapping for cracks.\n\n    2. If wrapping is cracked, remove wrapping and inspect main carry-through tube for corrosion.\n\n    3. Remove all corrosion on tube; if corrosion exceeds depth of 0.25 mm in one location or 2 per cent of the tube cross-sectional area, the main carry-through must be replaced. Nominal cross-sectional area of 262.5 sq. mm. Finish the tube with two coats of zinc chromate primer after corrosion removal. Rewrap the exposed tube with a fibreglass laminate using a minimum of 3 layers of MIL-C-9084 glass cloth or equivalent and chemical resistant resin such as Reichbold 33-402.\n\nNote: Local equivalents may be substituted for glass cloth and resin.\n\nCompliance: Unless already accomplished, within 25 hours’ time in service after 12 December 1978 and thereafter at every major inspection.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2067},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow technical scope. It addresses a specific structural defect in Call Air A-9 aircraft and has not expanded beyond the inspection and repair requirements for the wing struts carry-through tube."},"complexity_factors":["Precise engineering tolerances (0.25mm depth threshold, 2% cross-sectional area calculation)","Technical material specifications referencing military standards (MIL-C-9084)","Conditional procedural logic requiring nested if-then decisions (cracking leads to corrosion check leads to replacement or repair)","Domain-specific aviation terminology (hopper, bulkhead, time in service, major inspection)"],"plain_english_summary":"This rule requires owners/operators of Call Air A‑9 agricultural aircraft to inspect the wing struts’ carry‑through tube that runs through the chemical hopper for cracked fibreglass wrap and underlying metal corrosion. If corrosion exceeds 0.25 mm depth in any spot or affects more than 2% of the tube wall area, the tube must be replaced; otherwise strip rust, apply two coats of zinc‑chromate primer and rewrap with at least three layers of fibreglass. First check within 25 flight hours after 12 Dec 1978 and at every major inspection."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube","history":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube/history","analysis":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube/analysis","conflicts":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube/conflicts","importantCases":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube/important-cases","documents":"/api/acts/ad-ac-cla-6-wing-struts-carry-through-tube/documents"}}