{"id":"F2006B09485","name":"AD/EMB-110/45 - Rudder Tab System","slug":"ad-emb-110-45-rudder-tab-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54001,"registerId":"commonwealth-F2006B09485-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-110/45 - Rudder Tab System","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nEmbraer EMB-110 (Bandeirante) Series Aeroplanes\n\nAD/EMB-110/45 Rudder Tab System 12/91\n\nApplicability: Model EMB-110.\n\nRequirement: Action in accordance with the technical requirements of CTA AD 91-07-01 Amdt 39- 680.\n\nNote: Embraer SB110-027-0089 refers.\n\nCompliance: Within 1500 hours time in service after 12 December 1991 or by 12 August 1992; whichever occurs first.\n\nBackground: There has been several occurrences of significant vibration in the rudder system that has been traced to the existence of free play and lack of rigidity in the rudder tab system. This directive requires the installation of an improved rudder trim tab actuator and the addition of reinforcements to the vertical stabilizer rear spar. The effective date required by the CTA is extended by approximately three months.","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 mechanical defect in a specific aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 200 words)","Only one defined term (Model EMB-110 in the applicability section)","Single compliance pathway with clear deadline","No nested exceptions or conditional logic","Cross-reference to one external technical document (CTA AD 91-07-01) and one service bulletin (SB110-027-0089), but these are provided for reference rather than creating interpretive complexity","Plain language background explanation included"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\n- Requires owners and operators of **Embraer EMB-110 Bandeirante aircraft** to fix a known safety problem with the rudder (the moveable surface on the tail that steers the plane left and right).\n\n**The problem:**\n- Several aircraft experienced **dangerous vibrations in the rudder system**, caused by loose, wobbly components in the rudder tab system (a small adjustable surface on the rudder that helps keep the plane flying straight).\n\n**The fix:**\n- Install an improved **rudder trim tab actuator** (the motor/mechanism that moves the tab), and\n- Add **reinforcements to the vertical stabilizer rear spar** (structural strengthening at the back of the tail fin).\n\n**Who must comply:**\n- Anyone operating an Embraer EMB-110 aircraft in Australia.\n\n**When:**\n- Within 1,500 flight hours after 12 December 1991, **or** by 12 August 1992 — whichever comes first.\n\n**Why it matters:**\n- Rudder vibrations can escalate into loss of control or structural failure. This directive prevents accidents by forcing a specific repair before the aircraft can continue flying."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive confines action to the stated technical modifications (improved rudder trim-tab actuator and reinforcements to the vertical stabilizer rear spar) for EMB-110 aeroplanes and sets a compliance deadline. The only procedural change noted is an extension of the effective date required by the CTA by approximately three months; there is no expansion of applicability or additional obligations beyond the technical work and stated compliance timeframe. (Background; Applicability; Compliance; Requirement)."},"complexity_factors":["Narrow applicability (single aircraft model EMB-110) reduces regulatory scope.","Specific technical modifications required (actuator replacement and spar reinforcements) introduce engineering/maintenance complexity.","Compliance deadline tied to flight hours or a calendar date requires operational scheduling.","Dependency on external technical documents (CTA AD 91-07-01 Amdt 39-680 and Embraer SB110-027-0089) adds procedural steps and potential ambiguity if those documents are not immediately available.","Potential supply and maintenance-capacity constraints for parts and specialised labour increase implementation complexity for operators."],"plain_english_summary":"This AD requires all Embraer EMB‑110 (Bandeirante) aircraft to receive an improved rudder trim‑tab actuator and reinforcements to the vertical stabilizer rear spar to eliminate rudder vibration caused by free play and lack of rigidity. Operators must comply within 1,500 flight hours after 12 Dec 1991 or by 12 Aug 1992, following CTA AD 91‑07‑01 and Embraer SB110‑027‑0089; operators bear costs, parts and maintenance scheduling impacts."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-110-45-rudder-tab-system","history":"/api/acts/ad-emb-110-45-rudder-tab-system/history","analysis":"/api/acts/ad-emb-110-45-rudder-tab-system/analysis","conflicts":"/api/acts/ad-emb-110-45-rudder-tab-system/conflicts","importantCases":"/api/acts/ad-emb-110-45-rudder-tab-system/important-cases","documents":"/api/acts/ad-emb-110-45-rudder-tab-system/documents"}}