{"id":"F2006B03506","name":"AD/BAe 146/56 - Aileron Servo and Trim Tab Drive Brackets","slug":"ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43061,"registerId":"commonwealth-F2006B03506-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BAe 146/56 - Aileron Servo and Trim Tab Drive Brackets","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)  British Aerospace BAe 146 Series Aeroplanes\n\n \n\nAD/BAe 146/56 Aileron Servo and Trim Tab Drive Brackets 12/95\n\nDM\n\n \n\nApplicability: All Series BAe 146 aircraft.\n\n \n\nRequirement: Action in accordance with Avro International Aerospace Mandatory Service Bulletin 57-47.\n\n \n\nCompliance: As specified in the requirement document with the initial inspection before 28 September 1995.\n\n \n\nBackground:  The manufacturer received a report of corrosion on the bracket surface between the two tab drive flanges in the area of the two attachment bolts. This has given rise to cracking of the flanges at their base in severe corrosion cases.\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 discrete, single-issue airworthiness directive addressing a specific corrosion and cracking problem on a particular aircraft component. It has not expanded beyond its original safety purpose."},"complexity_factors":["Single, specific mechanical component addressed (aileron servo and trim tab drive brackets)","Only one mandatory action required (compliance with referenced service bulletin)","No defined terms section","Single applicability criterion (all BAe 146 series aircraft)","No nested exceptions or conditional logic","Clear, fixed compliance deadline","Short document (approximately 150 words of substantive content)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners and operators to fix a specific mechanical problem.\n\n**What it does:**\nOrders inspections and repairs of **aileron servo and trim tab drive brackets** on British Aerospace BAe 146 aircraft. These are metal brackets that help control the small hinged surfaces (trim tabs) on the wing's ailerons, which assist with steering the plane.\n\n**Why it matters:**\nThe manufacturer discovered **corrosion** (rust-like deterioration) and **cracking** where the bracket attaches to the tab drive flanges. If left unchecked, this could cause the control surfaces to fail — a serious flight safety risk.\n\n**Who must comply:**\nAll operators of BAe 146 series aircraft in Australia.\n\n**What must be done:**\nFollow the specific inspection and repair instructions in **Avro International Aerospace Mandatory Service Bulletin 57-47**, with the first inspection completed before 28 September 1995."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope as presented matches its stated intent in the text: it targets a specific structural/component issue (corrosion and potential cracking of the aileron servo and trim tab drive bracket flanges) on all BAe 146 series aircraft and prescribes actions by reference to the manufacturer's Mandatory Service Bulletin 57-47. The AD sets an initial inspection deadline (28 September 1995) and otherwise relies on the service bulletin for technical and ongoing requirements (Applicability; Requirement; Compliance; Background). There is no indication in the supplied text that the scope has been broadened or narrowed from that stated purpose."},"complexity_factors":["Single clearly defined applicability: all Series BAe 146 aircraft (Applicability)","Reliance on an external technical document (Avro Mandatory Service Bulletin 57-47) for procedures and remedial actions (Requirement)","A fixed initial compliance deadline (28 September 1995) but unspecified follow-up schedule in the AD text itself (Compliance; Requirement)","Technical nature of inspections/repairs (corrosion and flange cracking) requiring specialised maintenance skills (Background; Requirement)","Regulatory enforcement by CASA with limited procedural detail in the directive itself (Requirement)"],"plain_english_summary":"This directive requires inspection and any corrective action for the aileron servo and trim tab drive brackets on all BAe 146 aircraft because corrosion has caused flange cracking. Operators must complete an initial inspection by 28 September 1995 and follow Avro Mandatory Service Bulletin 57‑47 for further work; CASA enforces compliance and operators bear the inspection, repair and downtime costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets","history":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets/history","analysis":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets/analysis","conflicts":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets/conflicts","importantCases":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets/important-cases","documents":"/api/acts/ad-bae-146-56-aileron-servo-and-trim-tab-drive-brackets/documents"}}