{"id":"F2006B04948","name":"AD/CESSNA 150/6 - Vertical Fin","slug":"ad-cessna-150-6-vertical-fin","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44810,"registerId":"commonwealth-F2006B04948-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 150/6 - Vertical Fin","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)  Cessna 150, F150, 152 & F152 Series Aeroplanes\n\n \n\nAD/CESSNA 150/6 Vertical Fin 2/61\n\nApplicability: All models with S/Nos. 17001 to 17719 and 59001 to 59067. Requirement:  Action in accordance with Cessna SL No. 150-21 (Cessna SK 150-3). Compliance:               Forthwith.\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\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2296},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive remains tightly scoped to its original purpose: correcting a specific airworthiness issue with the vertical fin on defined Cessna aircraft models. It has not expanded beyond this safety-critical repair mandate."},"complexity_factors":["External technical references (Cessna Service Letter and Service Kit) contain the actual procedural details, not reproduced in the directive itself","Requires aircraft owner to cross-check specific serial numbers against aircraft registration records to determine applicability","Single sentence mandate with legal term 'forthwith' instead of a calendar date"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — a mandatory safety order issued by the Civil Aviation Safety Authority (CASA). ADs are legally binding instructions that require aircraft owners to fix specific unsafe conditions.\n\n**Who it affects:** Owners and operators of Cessna 150, F150, 152, and F152 aircraft with serial numbers between 17001–17719 or 59001–59067.\n\n**What you must do:** Immediately inspect or repair the **vertical fin** (the upright tail section of the aircraft) following the exact instructions in two manufacturer documents: *Cessna Service Letter No. 150-21* and *Cessna Service Kit 150-3*.\n\n**When:** **Forthwith** — meaning immediately, without delay. As soon as you become aware of this directive, you must ground the aircraft until the work is done.\n\n**Why it matters:** This addresses a specific safety defect in the tail section of these particular aircraft. Operating the aircraft without completing this action violates civil aviation law and poses a safety risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-150-6-vertical-fin","history":"/api/acts/ad-cessna-150-6-vertical-fin/history","analysis":"/api/acts/ad-cessna-150-6-vertical-fin/analysis","conflicts":"/api/acts/ad-cessna-150-6-vertical-fin/conflicts","importantCases":"/api/acts/ad-cessna-150-6-vertical-fin/important-cases","documents":"/api/acts/ad-cessna-150-6-vertical-fin/documents"}}