{"id":"F2006B09455","name":"AD/EMB-110/15 - Flap Actuators Ball Nut - Inspection","slug":"ad-emb-110-15-flap-actuators-ball-nut-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53906,"registerId":"commonwealth-F2006B09455-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-110/15 - Flap Actuators Ball Nut - Inspection","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)  Embraer EMB-110 (Bandeirante) Series Aeroplanes\n\n \n\nAD/EMB-110/15 Flap Actuators Ball Nut - Inspection 10/81 Applicability:              All models EMB-110 equipped with linear actuators P/Nos. D2246-3 and D2246-4. Document:               1. Embraer Alert S.B. No. 110-27-A54, or\n\n2. C.T.A. AD NR.81-07-01.\n\nCompliance: At the next 250 hourly inspection of actuators carried out after 30 September 1981. Background:               In addition to the repetitive 250 hourly inspection of actuators laid down in AD/EMB-\n\n110/8B, a once only inspection of the ball return tube retaining clamp is now required. Loosening of a ball return tube may cause loss of the balls and result in an asymmetric flap condition.\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 narrow, targeted safety directive addressing a specific mechanical defect in a specific aircraft type. The scope remains precisely limited to the identified safety risk (ball nut retention in flap actuators) and has not expanded beyond this original technical purpose."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined part numbers for applicability (D2246-3 and D2246-4)","Single compliance requirement with clear deadline","No nested exceptions or conditional logic","Simple cross-reference to one previous directive (AD/EMB-110/8B) and two source documents","Straightforward technical instruction without alternative compliance methods"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) for a specific type of aircraft: the **Embraer EMB-110 Bandeirante**.\n\n**What it does:**\nIt requires aircraft owners and operators to perform a **one-time inspection** of the flap actuator ball nuts on certain EMB-110 aircraft. Specifically, they must check the **ball return tube retaining clamp** — a small but critical component that keeps the ball bearings in place within the flap mechanism.\n\n**Who it affects:**\n- Owners and operators of **all EMB-110 models** fitted with linear actuators part numbers **D2246-3 and D2246-4**\n- Maintenance organisations servicing these aircraft\n\n**Why it matters:**\nIf the ball return tube comes loose, the ball bearings can fall out. This can cause the flaps on one wing to extend or retract differently from the other wing — an **asymmetric flap condition**. This creates a serious flight safety risk, potentially causing loss of control during takeoff or landing.\n\n**When to comply:**\nAt the next scheduled 250-hour inspection of the actuators that occurs **after 30 September 1981**.\n\n**Key point:** This inspection is **in addition to** an existing recurring 250-hour inspection already required under a previous directive (AD/EMB-110/8B). It is not replacing that requirement — it's adding an extra one-time check."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"This directive amends the existing inspection regime by adding a one‑time inspection of the ball return tube retaining clamp in addition to the already required repetitive 250‑hour actuator inspections (Background). It does not remove prior obligations; it creates an additional, time‑limited obligation triggered at the next scheduled 250‑hour actuator inspection after 30 September 1981 (Compliance)."},"complexity_factors":["Narrow technical scope limited to EMB‑110 aeroplanes with actuators P/N D2246‑3 and D2246‑4 (Applicability).","Clear, time‑triggered compliance requirement tied to the next 250‑hour actuator inspection after a fixed date (Compliance).","Dependence on two external technical documents for inspection procedure (Document), which adds a modest interpretive step.","Interaction with an existing AD (AD/EMB‑110/8B) described in Background, requiring awareness of prior maintenance obligations.","Potential operational complexity if defects are found (need for parts replacement or additional repairs), though not detailed in the text."],"plain_english_summary":"What this directive does (mechanics)\n\n- Requires a one‑time physical inspection of the flap actuators' ball return tube retaining clamp on certain Embraer EMB‑110 aeroplanes. The inspection must be done at the next 250‑hour actuator inspection carried out after 30 September 1981 (see \"Compliance\").\n- Applies to all EMB‑110 models that have linear actuators with part numbers D2246‑3 and D2246‑4 (see \"Applicability\").\n- The inspection procedure is to follow one of two specified documents: Embraer Alert Service Bulletin No. 110‑27‑A54 or C.T.A. AD NR.81‑07‑01 (see \"Document\").\n\nWhy it was issued (stated purpose)\n\n- The stated reason is that a loose ball return tube retaining clamp can allow the ball return tube to loosen and balls to be lost from the actuator. Loss of balls in the actuator can cause asymmetric flap conditions. The directive adds a once‑only clamp inspection in addition to the existing repetitive 250‑hour actuator inspections already required by AD/EMB‑110/8B (see \"Background\").\n\nWho this affects and who pays\n\n- Aircraft operators who own or fly Embraer EMB‑110 aeroplanes equipped with the specified actuator part numbers must organise and pay for the inspection. Maintenance providers and licensed maintenance personnel will carry out the inspection. Any remedial work (tightening or replacing clamps, replacing actuators or balls) will be paid by the operator.\n\nBehavioural and operational changes required\n\n- Operators must schedule the one‑time clamp inspection to coincide with the next scheduled 250‑hour actuator inspection after 30 September 1981 (\"Compliance\").\n- Maintenance personnel must consult one of the two referenced technical documents for the inspection procedure (\"Document\").\n- If the clamp or tube is found loose or missing balls, operators will need to take corrective action consistent with the referenced documents and usual airworthiness practices.\n\nCosts, incentives and trade‑offs\n\n- Direct costs: labour time at the next 250‑hour inspection and potential parts and repair costs if defects are found. These are concrete and immediate costs borne by operators (see \"Compliance\" and \"Background\").\n- Scheduling/opportunity cost: the inspection must be done at the next 250‑hour check, which may require planning maintenance slots or slightly extending a scheduled check to include the additional check.\n- Information dependency: the directive requires operators/maintainers to use one of two external technical documents. Accessing, interpreting and following those documents creates administrative and compliance work (see \"Document\").\n\nCompliance burden and implementation risk\n\n- Compliance is specific and time‑bound: the one‑time inspection is triggered by the next 250‑hour actuator inspection after a specified date, which makes the requirement easy to identify in maintenance planning (see \"Compliance\").\n- The requirement depends on correct identification of actuator part numbers D2246‑3 and D2246‑4, so operators must maintain accurate parts records (see \"Applicability\").\n- There is limited regulatory discretion described in the text: the AD prescribes the inspection and the referenced documents prescribe how to perform it. Interpreting or deviating from those documents would require formal approval under applicable procedures (implicitly necessary but not set out in this text).\n\nImplementation notes and trade‑offs for decisionmakers\n\n- The mechanical change is narrowly targeted: a once‑only clamp check added to an existing 250‑hour inspection regime. This concentrates the compliance cost on operators of affected aeroplanes and on the specific maintenance event (see \"Background\" and \"Compliance\").\n- The benefit claimed (preventing ball loss and asymmetric flap) is operationally specific; the directive’s cost is the inspection effort and any corrective work found necessary. The directive relies on routine maintenance opportunities to limit incremental downtime (see \"Compliance\").\n\nSource citations: Applicability; Document; Compliance; Background."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection","history":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection/history","analysis":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection/analysis","conflicts":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection/conflicts","importantCases":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection/important-cases","documents":"/api/acts/ad-emb-110-15-flap-actuators-ball-nut-inspection/documents"}}