{"id":"F2008L03328","name":"AD/AC-CLA/6 Amdt 1 - Wing Struts Carry-Through Tube","slug":"ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":120174,"registerId":"commonwealth-F2008L03328-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Aircraft Parts and Development (CALL AIR","sectionType":"division","heading":"Aircraft Parts and Development (CALL AIR) A-9 Series Aeroplanes","content":"### Aircraft Parts and Development (CALL AIR) A-9 Series Aeroplanes\n\n| AD/AC-CLA/6 Amdt 1 | Wing Struts Carry-Through Tube | 10/2008 |\n| ------------------ | ------------------------------ | ------- |\n\n| Applicability: | All models A-9, A-9A and A-9B with wing struts carry through tube running through hopper. |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | To prevent failure of the main carry-through tube perform the following:1. 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.2. If wrapping is cracked, remove wrapping and inspect main carry-through tube for corrosion.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 ofMIL-C-9084 glass cloth or equivalent and chemical resistant resin such as Reichbold 33-402.Note: 1: Local equivalents may be substituted for glass cloth and resin.Note 2: FAA AD 78-20-06 refers. |\n| Compliance: | At intervals of three years after 12 December 1978. |\n| | This Amendment becomes effective on 25 September 2008. |\n| Background: | This AD has been amended to remove reference to “major inspection” which is no longer required by legislation. Reference to FAA AD 78-20-06 also included. |\n\n| | The AD was originally raised in 1979 following reports of severe corrosion of the wing strut carry-through tube being found in a number of overseas aeroplanes, causing a fatal accident due failure of the wing strut carry-through tube. |\n| --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n\n![](image.001.png) \nDavid Villiers \nDelegate of the Civil Aviation Safety Authority\n\n7 August 2008","sortOrder":0},{"sectionNumber":"AD/AC-CLA/6 Amdt 1","sectionType":"part","heading":"AD/AC-CLA/6 Amdt 1","content":"## AD/AC-CLA/6 Amdt 1","sortOrder":1},{"sectionNumber":"Wing Struts Carry-Through Tube","sectionType":"part","heading":"Wing Struts Carry-Through Tube","content":"## Wing Struts Carry-Through Tube","sortOrder":2},{"sectionNumber":"10/2008","sectionType":"part","heading":"10/2008","content":"## 10/2008","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment makes no substantive change to the safety requirements. It is purely administrative — removing an obsolete legislative reference ('major inspection') and adding a cross-reference to the FAA equivalent. The inspection intervals, corrosion limits, and repair procedures remain identical to the 1979 original."},"complexity_factors":["Single, discrete technical requirement with clear sequential steps","Only 3 defined measurements (0.25mm depth, 2% cross-sectional area, 262.5 sq. mm nominal area)","No cross-references to other legislation beyond a single FAA AD reference and material specifications","Simple compliance trigger: fixed 3-year interval from a specific historical date","Limited applicability: narrow aircraft model range with specific structural feature","Plain procedural language with minimal conditional logic (essentially: inspect → if cracked then inspect further → if corroded beyond limits then replace else repair)"],"plain_english_summary":"This AD mandates triennial inspection of the fibreglass-wrapped wing-strut support tube that runs through the chemical hopper on CALL AIR A‑9/A‑9A/A‑9B agricultural aeroplanes. If the wrap is cracked the metal tube must be exposed and checked for corrosion; limited corrosion may be cleaned, primed and rewrapped, but deeper or widespread corrosion requires tube replacement. It responds to corrosion-related wing failures and updates paperwork and a cross-reference to the equivalent FAA directive."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This amendment narrows procedural language by removing a reference to a prior 'major inspection' requirement while keeping the original applicability to A‑9/A‑9A/A‑9B models and the substantive technical measures. The safety scope (inspect/repair/replace the carry‑through tube) remains, but procedural obligations and referenced inspection terminology were changed (Background; Requirement)."},"complexity_factors":["Technical inspection location and access: tube located 625 mm aft of the hopper forward bulkhead and 150 mm below hopper surface, requiring removal of the hopper top to inspect (Requirement).","Precise acceptance and replacement criteria: corrosion removal allowed but replacement required if depth >0.25 mm in one place or exceeds 2% of nominal 262.5 mm² cross‑section (Requirement).","Repair specification detail: finish with two coats of zinc chromate primer, rewrap with minimum 3 layers of MIL‑C‑9084 glass cloth (or equivalent) and specified chemical‑resistant resin such as Reichbold 33‑402 (Requirement).","Recurring compliance timing tied to a historic baseline: inspections at three‑year intervals counted from 12 December 1978; effective date of this amendment is 25 September 2008 (Compliance).","Standards and equivalence language: allows 'local equivalents' for materials and references an external FAA AD (78‑20‑06), creating dependency on interpretation of equivalence (Requirement; Background).","Enforcement and execution gaps: the instrument mandates action but does not specify who (licensed maintenance organisation, owner, or inspector) must perform or certify measurements and repairs, leaving procedural discretion (Applicability; Requirement).","Recordkeeping and measurement method ambiguity: depth and area calculations require defined measurement methods and tolerances which are not described, affecting repeatability of compliance decisions (Requirement).","Amendment change: removal of the prior 'major inspection' reference alters procedural expectation without changing the core technical requirements, requiring implementers to reconcile prior schedules (Background)."],"plain_english_summary":"Requires owners/operators of CALL AIR A-9, A-9A and A-9B aeroplanes with the wing‑strut carry‑through tube routed through the hopper to inspect, repair or replace that tube to prevent structural failure. It specifies where to inspect, a three‑year inspection cycle, corrosion-removal and replacement thresholds (0.25 mm depth or 2% of a 262.5 mm² cross‑section), and primer plus fibreglass rewrap standards (Requirement; Compliance). Owners/operators pay inspection and repair costs; the Civil Aviation Safety Authority issues the directive and affected aircraft must adopt periodic inspection and remediation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube","history":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube/history","analysis":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube/analysis","conflicts":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube/conflicts","importantCases":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube/important-cases","documents":"/api/acts/ad-ac-cla-6-amdt-1-wing-struts-carry-through-tube/documents"}}