{"id":"F2006B05486","name":"AD/PA-23/59 - Wing Rear Spar - Inspection","slug":"ad-pa-23-59-wing-rear-spar-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46305,"registerId":"commonwealth-F2006B05486-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/59 - Wing Rear Spar - Inspection","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-23 (Apache and Aztec) Series Aeroplanes\n\n \n\nAD/PA-23/59 Wing Rear Spar - Inspection 11/73\n\nApplicability: All model PA-23-150 and PA-23-160 with S/Nos. 23-1 to 23-2046. Document:  Piper SL No. 672.\n\nCompliance: Within 100 hours time in service after 30 November 1973 and thereafter at intervals not exceeding one year.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1667},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow scope: a specific structural inspection requirement for defined Piper aircraft models. There is no evidence of scope expansion beyond the original wing rear spar inspection mandate."},"complexity_factors":["Single, specific applicability clause covering only two aircraft models with defined serial number ranges","Simple two-step compliance schedule (initial inspection plus recurring annual requirement)","No defined terms section or legislative cross-references","Brief document length with minimal conditional logic"],"plain_english_summary":"**What this is:** An Airworthiness Directive (safety rule) requiring owners to inspect the wing rear spar on specific Piper aircraft to prevent structural failure.\n\n**Who it affects:**\n- Owners and operators of **Piper PA-23 Apache and Aztec** aeroplanes\n- Specifically models **PA-23-150 and PA-23-160** with serial numbers **23-1 through 23-2046**\n\n**What you must do:**\nInspect the wing rear spar following the procedures in **Piper Service Letter No. 672**:\n- **First inspection:** Within 100 hours of flight time after 30 November 1973\n- **Then:** Repeat the inspection at least once every year\n\n**Why it matters:**\nThis addresses potential safety defects in the wing structure. Operating the aircraft without this inspection makes it **unairworthy** — meaning it is illegal to fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection","history":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection/history","analysis":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection/analysis","conflicts":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection/conflicts","importantCases":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection/important-cases","documents":"/api/acts/ad-pa-23-59-wing-rear-spar-inspection/documents"}}