{"id":"F2006B06839","name":"AD/SD3-30/37 - Elevator Control Torque Tube Bearing Housing","slug":"ad-sd3-30-37-elevator-control-torque-tube-bearing-housing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114703,"registerId":"commonwealth-F2006B06839-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SD3-30/37 - Elevator Control Torque Tube Bearing Housing","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)  Short SD3-30 Series Aeroplanes\n\n \n\nAD/SD3-30/37 Elevator Control Torque Tube Bearing Housing 3/99\n\nApplicability: All SD3-30 aircraft.\n\n \n\nRequirement: Action in accordance with Shorts Mandatory Service Bulletin SD330-27-37. Compliance:              Before 25 September 1999.\n\nThis Airworthiness Directive becomes effective on 25 March 1999.\n\n \n\nBackground:  Experience shows that existing bolts securing the elevator control torque tube bearing housing retaining plate to pilot’s seat pedestal have been found loose; probably because of the significance of the structure has not been recognised during maintenance.\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":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive (AD) — a targeted safety instrument with a narrow, specific purpose. It has not expanded beyond its original intent of addressing a specific mechanical defect in a specific aircraft type. ADs are by design limited in scope to particular airworthiness issues."},"complexity_factors":["Very short document (approximately 150 words)","Only 1 defined term implicitly referenced (the service bulletin)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Single unconditional requirement with clear deadline","No exceptions, exemptions, or conditional logic","Technical aviation terminology is present but explained through context (elevator control, torque tube, bearing housing)"],"plain_english_summary":"This is a **safety order** issued by Australia's Civil Aviation Safety Authority (CASA) for a specific type of aircraft called the **Short SD3-30** (a small regional turboprop plane, also known as the Short 330).\n\n**What it does:**\n- Orders all operators of SD3-30 aircraft to inspect and fix a specific mechanical problem with the **elevator control system** — the part of the plane that controls up-and-down movement (pitch).\n- The problem involves **loose bolts** that hold a bearing housing (a metal casing that supports a rotating shaft) for the torque tube (a shaft that transmits twisting force) near the pilot's seat.\n\n**Why it matters:**\n- Loose bolts in the flight controls are extremely dangerous. If the elevator controls fail or malfunction, the pilots may lose the ability to control the aircraft's pitch, potentially leading to loss of control and crash.\n- The issue was discovered because maintenance crews weren't recognizing how important this particular structure was during routine checks.\n\n**Who must act:**\n- Anyone who owns or operates a Short SD3-30 aircraft.\n\n**What they must do:**\n- Follow the instructions in **Shorts Mandatory Service Bulletin SD330-27-37** (a technical repair notice from the manufacturer) before **25 September 1999**.\n\n**When it took effect:**\n- 25 March 1999 (giving operators 6 months to comply)."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is limited to all SD3-30 aircraft and requires actions specified in Shorts Mandatory Service Bulletin SD330-27-37 to address loose bolts on the elevator control torque tube bearing housing retaining plate. The text shows no expansion or narrowing of scope from that stated purpose: applicability, required action, effective date and compliance deadline are all explicit in the AD."},"complexity_factors":["Direct and narrow subject matter: single component (elevator control torque tube bearing housing) and single aircraft type (SD3-30).","Cross-reference to an external technical document (Shorts Mandatory Service Bulletin SD330-27-37) for detailed work — requires access to that bulletin.","Clear, single compliance deadline and effective date (limited scheduling complexity).","No multiple compliance options, alternatives, or derogations specified in the AD text (low procedural complexity).","Issued under Part 39 regulatory framework — administrative authority present but no complex legal exceptions or conditional provisions in the text."],"plain_english_summary":"This Airworthiness Directive from the Civil Aviation Safety Authority requires all Shorts SD3‑30 operators to carry out the work specified in Shorts Mandatory Service Bulletin SD330‑27‑37 by 25 September 1999. It was issued because bolts retaining the elevator control torque‑tube bearing housing plate were found loose, likely due to maintenance oversight. The AD compels operators and maintenance organisations to inspect and secure/repair that structure, imposing associated time, labour and parts costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing","history":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing/history","analysis":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing/analysis","conflicts":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing/conflicts","importantCases":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing/important-cases","documents":"/api/acts/ad-sd3-30-37-elevator-control-torque-tube-bearing-housing/documents"}}