{"id":"F2006B03937","name":"AD/BEECH 50/12 - Elevator Control Surfaces","slug":"ad-beech-50-12-elevator-control-surfaces","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43546,"registerId":"commonwealth-F2006B03937-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 50/12 - Elevator Control Surfaces","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)  Beechcraft 50 (Twin Bonanza) Series Aeroplanes\n\n \n\nAD/BEECH 50/12 Elevator Control Surfaces NK\n\nApplicability: All models prior to S/Nos. DH-170 and FH-89 except H-1 to H-11.\n\n \n\nRequirement: Action in accordance with Beechcraft SB B50 - No. 35; C50 - No. 26; D50 - No. 20; E50 - No. 11; F50 - No. 4.\n\n \n\nCompliance: At intervals not exceeding 100 hours’ time in service.\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":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD explicitly states its applicability (all models prior to S/Nos. DH-170 and FH-89 except H-1 to H-11) and prescribes required actions by reference to specific Beechcraft service bulletins, to be repeated every 100 hours. Nothing in the text indicates an alteration of that scope from the directive as written; the AD does not expand or narrow applicability beyond the stated serial-number and model exclusions."},"complexity_factors":["References external technical documents (multiple Beechcraft service bulletins) rather than setting detailed technical steps in the AD (Requirement).","Precise applicability limited by serial-number cutoffs and model exceptions (Applicability).","Recurring compliance obligation with a fixed interval (every 100 hours’ time in service) introduces ongoing administrative and operational scheduling requirements (Compliance).","Regulatory placement under Part 39 requires legal obedience but delegates technical detail to manufacturer bulletins (header; Requirement)."],"plain_english_summary":"This AD mandates recurring maintenance of elevator control surfaces on Beechcraft 50 (Twin Bonanza) aircraft built before serial numbers DH‑170 and FH‑89 (excluding H‑1 to H‑11), by following specific Beechcraft service bulletins at intervals not exceeding 100 hours’ time-in-service. Operators/owners must arrange and pay for compliance. It limits operator discretion, creates recurring costs and demand for maintenance providers, and depends on the availability and clarity of the referenced service bulletins and parts/personnel."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive for a specific aircraft type. It has not expanded beyond its original purpose of mandating elevator inspections for early-model Beechcraft 50 series aircraft."},"complexity_factors":["Very short document (under 200 words)","Only 4 operative provisions: applicability, requirement, compliance, and reference to external technical documents","Single cross-reference to manufacturer service bulletins (SBs) rather than legislative text","No defined terms section — uses plain aviation terminology","No nested conditions or exceptions beyond the serial number carve-out","Straightforward temporal trigger (100 hours time in service)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nRequires owners and operators of certain **Beechcraft 50 series aeroplanes** (known as \"Twin Bonanzas\") to inspect and maintain the **elevator control surfaces** (the movable parts on the tail that make the plane pitch up and down).\n\n**Who must follow it:**\nAnyone who owns or operates a Beechcraft 50 model **built before specific serial numbers** (DH-170 and FH-89), **excluding** the very early H-1 through H-11 models.\n\n**What they must do:**\nFollow the procedures in specific **Beechcraft Service Bulletins** (official manufacturer instructions) — the exact bulletin depends on which model variant you have (B50, C50, D50, E50, or F50).\n\n**When:**\nThese checks must be done **every 100 hours of flight time** (\"time in service\" means actual flying hours, not just calendar time).\n\n**Why it matters:**\nElevator problems can cause loss of control. This directive prevents accidents by forcing regular inspections of a critical flight control system on these older aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-50-12-elevator-control-surfaces","history":"/api/acts/ad-beech-50-12-elevator-control-surfaces/history","analysis":"/api/acts/ad-beech-50-12-elevator-control-surfaces/analysis","conflicts":"/api/acts/ad-beech-50-12-elevator-control-surfaces/conflicts","importantCases":"/api/acts/ad-beech-50-12-elevator-control-surfaces/important-cases","documents":"/api/acts/ad-beech-50-12-elevator-control-surfaces/documents"}}