{"id":"F2006B02097","name":"AD/AC/39 - Wing Front Spar Lower Cap - Inspection","slug":"ad-ac-39-wing-front-spar-lower-cap-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41327,"registerId":"commonwealth-F2006B02097-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AC/39 - Wing Front Spar Lower Cap - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue 2/1968,Aircraft below 5700 kg,Twin Commander (Gulfstream/Rockwell/ Aerocommander 500, 600 and 700) Series Aeroplanes,Wing Front Spar Lower Cap - Inspection,39\ntitle: Airworthiness Directive - AD/AC/39 - Wing Front Spar Lower Cap - Inspection\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)  Twin Commander (Gulfstream/Rockwell/ Aerocommander 500, 600 and 700) Series Aeroplanes\n\n \n\nAD/AC/39 Wing Front Spar Lower Cap - Inspection 2/68\n\nApplicability: All 560E, 680 and 680E models.\n\n \n\nRequirement:  Inspect the wing front spar lower cap between wing stations 67 and 86, left and right hand sides, using radiographic technical DCA NDI/R/1 or other technique approved by the Secretary, for damaged or double drilled holes, poor rivet fit or cracking.\n\n \n\nCompliance: Within 100 hours’ time in service after 22 February 1968.\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":1660},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original scope as a targeted safety inspection for specific Twin Commander aircraft models. It has not expanded beyond its initial purpose of ensuring structural integrity of wing spar lower caps."},"complexity_factors":["Single, unambiguous maintenance requirement","No nested exceptions or conditional clauses","Minimal cross-referencing (references only one technical standard: DCA NDI/R/1)","Very short length (less than one page)","Clear applicability limited to three specific aircraft models"],"plain_english_summary":"Owners/operators of Twin Commander 560E, 680 and 680E (Gulfstream/Rockwell/Aero Commander 500/600/700 series) must perform a mandatory structural inspection of the wing front spar lower cap (wing stations 67–86 on both sides). The inspection uses radiographic (X‑ray) methods or an authority‑approved alternative to detect damaged/incorrectly drilled holes, loose rivets, or cracks. These defects risk catastrophic wing failure. The inspection was required within 100 flight hours after 22 Feb 1968."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection","history":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection/history","analysis":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection/analysis","conflicts":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection/conflicts","importantCases":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection/important-cases","documents":"/api/acts/ad-ac-39-wing-front-spar-lower-cap-inspection/documents"}}