{"id":"F2006B05455","name":"AD/PA-23/24 - Stabilator Tab Horn - Inspection","slug":"ad-pa-23-24-stabilator-tab-horn-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46209,"registerId":"commonwealth-F2006B05455-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/24 - Stabilator Tab Horn - 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-23/24 Stabilator Tab Horn - Inspection 11/71\n\nApplicability: Model PA-23-250 with S/Nos. 27-1 to 27-432 not modified in accordance with SB 199A.\n\n \n\nDocument: Piper SB No. 199.\n\n \n\nCompliance: At each daily inspection after 30 March 1961 until modified in accordance with SB 199A.\n\n \n\nNote: This inspection may be performed and certified by the pilot.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1774},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope, targeting only the inspection of stabilator tab horns on specific Piper PA-23-250 aircraft within the defined serial number range. It has not expanded beyond this specific safety issue since its issuance."},"complexity_factors":["Narrow applicability limited to specific aircraft model and serial number range","Cross-reference to external technical document (Piper Service Bulletin No. 199)","Conditional compliance endpoint (\"until modified in accordance with SB 199A\")","Technical aviation terminology requiring domain knowledge (stabilator, tab horn)"],"plain_english_summary":"This directive mandates **daily safety inspections** for a specific mechanical part on vintage **Piper Apache/Aztec aircraft**.\n\n**Who it affects:**\nOwners of **Piper PA-23-250** aeroplanes with serial numbers **27-1 through 27-432**—provided the aircraft hasn't already been modified according to Service Bulletin 199A (a manufacturer-issued repair instruction).\n\n**What you must do:**\nInspect the **stabilator tab horn** (the hinge-point connecting the aircraft's horizontal tail surface to its control system) **at every daily inspection**, starting from 30 March 1961 and continuing until the aircraft is permanently modified per SB 199A.\n\n**The unusual bit:**\nUnlike most maintenance tasks that require a licensed aircraft mechanic, **the pilot can legally perform and certify this inspection themselves**—a rare delegation of maintenance authority to the person actually flying the aircraft.\n\n**Why it exists:**\nThis addresses a potential structural or mechanical defect in the tail assembly that could compromise the pilot's ability to control the aircraft's pitch if left unchecked."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection","history":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection/history","analysis":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection/analysis","conflicts":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection/conflicts","importantCases":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection/important-cases","documents":"/api/acts/ad-pa-23-24-stabilator-tab-horn-inspection/documents"}}