{"id":"F2006B05393","name":"AD/PA-18/14 - Rear Fuselage Tail Plane Support Tubes","slug":"ad-pa-18-14-rear-fuselage-tail-plane-support-tubes","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46015,"registerId":"commonwealth-F2006B05393-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-18/14 - Rear Fuselage Tail Plane Support Tubes","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)  Piper PA-18 and 19 (Super Cub) Series Aeroplanes\n\n \n\nAD/PA-18/14 Rear Fuselage Tail Plane Support Tubes 5/95\n\nApplicability: All PA-18 aircraft.\n\n \n\nRequirement: Visually inspect, using a torch and mirror, the fuselage tubular structure near the horizontal stabiliser attachment lugs. Pay particular attention to the under-side of the tubes and welded joints.\n\n \n\nCompliance: Inspect before 5 000 hours time in service, or before 50 hours time in service after 27 April 1995, whichever occurs last.\n\n \n\nBackground:  Two instances have been reported of cracked tubes under the tailplane support lugs. Failure of these tubes could cause loss of the tailplane and loss of the aeroplane. A single inspection is called up at this time to determine the extent of the problem.\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":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2454},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original laser-focused scope: a specific one-off structural inspection for Piper PA-18 aircraft tailplane support tubes. It has not crept beyond the original safety concern regarding cracked tubes reported in 1995."},"complexity_factors":["Single, unambiguous inspection requirement with no exceptions or sub-clauses","No defined terms section or glossary requiring cross-referencing","Only simple temporal arithmetic ('whichever occurs last') for compliance timing","Zero cross-references to other legislation, regulations, or technical standards","Extremely concise format typical of airworthiness directives (under 150 words of substance)"],"plain_english_summary":"This directive requires owners/operators of Piper PA-18 Super Cub aircraft to perform a one‑time visual inspection of the rear-fuselage metal tubes that support the tailplane, using a torch and mirror to check welded joints and undersides for cracks.\n\nIt responds to two reported tube failures that could allow tailplane detachment and catastrophic loss of control; it must be done by the later of 5,000 flight hours or 50 hours after 27 April 1995."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes","history":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes/history","analysis":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes/analysis","conflicts":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes/conflicts","importantCases":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes/important-cases","documents":"/api/acts/ad-pa-18-14-rear-fuselage-tail-plane-support-tubes/documents"}}