{"id":"F2006B09510","name":"AD/EMB-120/22 - Wing and Empennage Leading Edge","slug":"ad-emb-120-22-wing-and-empennage-leading-edge","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54074,"registerId":"commonwealth-F2006B09510-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-120/22 - Wing and Empennage Leading Edge","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-120 (Brasilia) Series Aeroplanes\n\n \n\nAD/EMB-120/22 Wing and Empennage Leading Edge 1/98\n\nApplicability: All models EMB-120 aircraft.\n\n \n\nRequirement: Inspect in accordance with Embraer Alert Service Bulletin 120-51-A004.\n\n \n\nNote: CTA AD 97-09-07 Amdt 39-802 refers.\n\n \n\nCompliance: Unless already accomplished, within 75 hours time in service after 1 January 1998.\n\n \n\nThis airworthiness directive becomes effective on 1 January 1998.\n\n \n\nBackground: An occurrence was reported of delaminations in the wing leading edge top layer, immediately behind the ice boot upper edge. This Directive requires a visual inspection for erosion, delamination and condition of sealing and anti-static paint.\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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive, as written, implements a targeted inspection requirement for all EMB-120 aircraft to detect delamination, erosion, and deficient sealing/anti‑static paint following a reported occurrence. The source text states that requirement, specifies the inspection method by reference to Embraer Alert Service Bulletin 120-51-A004, and sets the compliance deadline. The document does not indicate any narrowing or broadening of that stated objective compared with the directive’s own stated purpose."},"complexity_factors":["Single, narrowly targeted action (visual inspection) reduces procedural complexity.","Mandatory linkage to an external document (Embraer Alert Service Bulletin 120-51-A004) requires operators to obtain and interpret manufacturer guidance.","Short compliance window (75 hours time in service after 1 January 1998) increases scheduling pressure and operational coordination.","Applicability to all EMB-120 models creates broad coverage but does not add technical variation within the AD text.","The AD does not specify in‑text corrective actions or pass/fail criteria, leaving follow-up decisions to the referenced service bulletin and maintenance personnel.","Cross-reference to a foreign AD (CTA AD 97-09-07 Amdt 39-802) introduces an additional document to consult for context or consistency."],"plain_english_summary":"What this instrument does, mechanically\n\n- Requires an inspection of all Embraer EMB-120 aeroplanes, carried out in accordance with Embraer Alert Service Bulletin 120-51-A004. (Requirement: \"Inspect in accordance with Embraer Alert Service Bulletin 120-51-A004.\")\n- Sets the compliance window: the inspection must be done within 75 hours time in service after 1 January 1998, unless already done. (Compliance: \"within 75 hours time in service after 1 January 1998.\")\n- Makes the directive effective from 1 January 1998. (\"This airworthiness directive becomes effective on 1 January 1998.\")\n\nWho is affected\n\n- Owners and operators of all models of the Embraer EMB-120 aircraft. (Applicability: \"All models EMB-120 aircraft.\")\n\nStated reason and what to look for\n\n- The directive cites a reported occurrence of delaminations in the wing leading edge top layer, immediately behind the ice boot upper edge. To address that, it requires a visual inspection for erosion, delamination, and the condition of sealing and anti-static paint. (Background: \"An occurrence was reported of delaminations...\" and \"This Directive requires a visual inspection for erosion, delamination and condition of sealing and anti-static paint.\")\n\nPractical implications, incentives and costs (source-cited)\n\n- Direct compliance action: Operators must obtain and follow Embraer Alert Service Bulletin 120-51-A004 to perform the inspection. (Requirement: \"Inspect in accordance with Embraer Alert Service Bulletin 120-51-A004.\")\n- Who pays: The operator/owner bears the cost of carrying out the inspection and any follow-up actions that the service bulletin or maintenance practice require (the AD mandates the inspection but directs compliance via the Embraer service bulletin). (Requirement and Applicability cited above.)\n- Compliance burden: The action is a visual inspection targeting specific locations and conditions (erosion, delamination, sealing, anti‑static paint). The AD sets a short compliance window (75 hours time in service after 1 January 1998), which can require scheduling maintenance soon after the effective date. (Compliance and Background cited above.)\n- Decision‑making and discretion: The AD mandates inspection per the Embraer service bulletin rather than prescribing detailed corrective steps within the AD text itself. That delegates detailed inspection technique and any identified repair or follow‑up thresholds to the service bulletin (and hence to the manufacturer’s guidance/approved maintenance practices). (Requirement: reference to the Embraer Alert Service Bulletin.)\n- Implementation risks and practical trade‑offs: Operators must obtain the referenced service bulletin and interpret its instructions; the AD does not include in‑text criteria for ‘‘pass/fail’’ or corrective action, so proper compliance depends on the clarity and availability of the Embraer document and competent maintenance judgement. Immediate scheduling to meet the 75‑hour window may impose aircraft downtime or rearrangement of operations. (Requirement and Compliance cited above.)\n\nCross references\n\n- The AD notes a related foreign airworthiness directive: CTA AD 97-09-07 Amdt 39-802. (Note: \"CTA AD 97-09-07 Amdt 39-802 refers.\")\n\nNet effect\n\n- Mechanically, the instrument imposes a mandatory, time‑limited inspection obligation on all EMB-120 operators to identify specific damage (erosion, delamination, sealing, anti‑static paint condition) described in the background report, using the procedures in Embraer Alert Service Bulletin 120-51-A004. (Applicability, Requirement, Compliance and Background cited above.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific airworthiness concern on a single aircraft type. It has not expanded beyond its original purpose of mandating inspection for leading edge delamination."},"complexity_factors":["Extremely short document (under 200 words)","Only 1 substantive requirement (inspect per referenced service bulletin)","No defined terms section","Single applicability criterion (all EMB-120 models)","Simple compliance deadline (75 hours time-in-service from fixed date)","No cross-references to other legislation beyond a single note about a related foreign directive","No conditional logic, exceptions, or nested provisions"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners and operators to fix a specific safety problem.\n\n**What it does:** It orders all owners and operators of **Embraer EMB-120 \"Brasilia\" aircraft** (a regional turboprop plane) to inspect the **wing and tail leading edges** (the front edges of the wings and tail surfaces) for damage.\n\n**The specific problem:** The leading edge's top layer can **delaminate** (peel apart in layers) right behind the \"ice boot\" — a rubber de-icing strip. The inspection must check for:\n- Erosion (wear from wind/rain)\n- Delamination (layer separation)\n- Condition of sealing and anti-static paint\n\n**Who must comply:** Anyone operating an EMB-120 aircraft in Australia.\n\n**When:** The inspection had to be done within **75 hours of flight time** after 1 January 1998, unless already completed.\n\n**Why it matters:** Delamination and erosion on leading edges can compromise structural integrity and aerodynamic performance, potentially affecting aircraft control — especially critical given these surfaces also house de-icing equipment for flight in icing conditions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge","history":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge/history","analysis":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge/analysis","conflicts":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge/conflicts","importantCases":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge/important-cases","documents":"/api/acts/ad-emb-120-22-wing-and-empennage-leading-edge/documents"}}