{"id":"F2006B09507","name":"AD/EMB-120/2 - APU Electronic Control Unit","slug":"ad-emb-120-2-apu-electronic-control-unit","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54065,"registerId":"commonwealth-F2006B09507-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-120/2 - APU Electronic Control Unit","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-120/2 APU Electronic Control Unit 4/91\n\nApplicability: All Embraer 120 aircraft as detailed in the Requirement Document.\n\n \n\nRequirement: Action in accordance with the technical requirements of Brazilian AD 90-09-02 R1 dated 14 January 1991.\n\n \n\nNote: Embraer SB NR 120-053-0049 also refers.\n\n \n\nCompliance: As specified in the Requirement Document with an effective date of 18 April 1991.\n\n \n\nBackground: It has been determined that the EMB 120 APU Electronic Control Unit may be subject to accidental water contamination during aircraft washing which may result in malfunction of the APU overspeed control which could affect safety of flight.\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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument implements the technical actions of Brazilian AD 90-09-02 R1 for EMB-120 APU Electronic Control Units and applies to all EMB-120 aircraft as identified in the Requirement Document. The text does not indicate an expansion or narrowing of scope beyond adopting that foreign AD and requiring compliance by the stated effective date. (Applicability; Requirement; Compliance)"},"complexity_factors":["Short, single-issue directive focused on APU Electronic Control Unit (limited subject matter). (Background)","Directive cross-references an external foreign airworthiness directive for all technical details (Brazilian AD 90-09-02 R1). (Requirement)","Relies on a separate Requirement Document for aircraft applicability and compliance timing, creating a dependency on another document. (Applicability; Compliance)","Refers to an Embraer service bulletin for additional information but does not include procedures or costs in the text. (Note)","No enforcement, exemption, or alternative-compliance language included, leaving implementation detail to operators and referenced documents. (Compliance; Requirement)"],"plain_english_summary":"This directive requires operators of specified Embraer EMB-120 aircraft to carry out the technical actions set out in Brazilian AD 90-09-02 R1 (and related Embraer service information) to address a risk that water ingress during washing can contaminate the APU electronic control unit and cause overspeed control failure. \n\nIt affects listed EMB-120 owners/operators, must be completed by the effective date, and obliges operators to obtain and follow the referenced documents (costs borne in practice by operators)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow airworthiness directive addressing a specific technical defect in a specific aircraft type. It has not expanded beyond its original purpose of ensuring APU control unit integrity."},"complexity_factors":["Very short document (under 200 words)","Only 1 defined term implicitly referenced (the 'Requirement Document' is Brazilian AD 90-09-02 R1)","No nested conditional logic or exceptions","Single straightforward requirement: comply with foreign airworthiness directive","No cross-references to Australian legislation beyond the enabling regulation (CAR 1998 Part 39)","Simple cause-and-effect structure (water contamination → malfunction → safety risk → mandatory action)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nOrders owners and operators of **Embraer EMB-120 \"Brasilia\" aircraft** to take specific action to fix a safety problem with the **APU Electronic Control Unit** (the Auxiliary Power Unit is a small engine that provides power when the main engines are off).\n\n**The problem:**\nWater can accidentally get into this control unit during aircraft washing. This could cause the APU's overspeed protection to fail, potentially creating a dangerous situation in flight.\n\n**What must be done:**\nOperators must follow the technical instructions in **Brazilian AD 90-09-02 R1** (dated 14 January 1991). This references an Embraer Service Bulletin (SB 120-053-0049) which contains the actual repair or inspection procedure.\n\n**Who it affects:**\nAnyone operating Embraer EMB-120 aircraft in Australia.\n\n**Why it matters:**\nAPU overspeed failures can damage the aircraft or affect flight safety. This directive ensures the problem is fixed before it causes an incident.\n\n**Compliance deadline:**\nBy 18 April 1991 (now long past — this is a historical directive)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-120-2-apu-electronic-control-unit","history":"/api/acts/ad-emb-120-2-apu-electronic-control-unit/history","analysis":"/api/acts/ad-emb-120-2-apu-electronic-control-unit/analysis","conflicts":"/api/acts/ad-emb-120-2-apu-electronic-control-unit/conflicts","importantCases":"/api/acts/ad-emb-120-2-apu-electronic-control-unit/important-cases","documents":"/api/acts/ad-emb-120-2-apu-electronic-control-unit/documents"}}