{"id":"F2006B11376","name":"AD/MU-2/46 - Anti-Ice and De-Ice Systems","slug":"ad-mu-2-46-anti-ice-and-de-ice-systems","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57277,"registerId":"commonwealth-F2006B11376-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MU-2/46 - Anti-Ice and De-Ice Systems","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)  Mitsubishi MU-2 Series Aeroplanes\n\n \n\nAD/MU-2/46 Anti-Ice and De-Ice Systems 5/90\n\nApplicability: Model MU2.\n\n \n\nRequirement: Carry out an operation check of the airframe and engine anti-ice and de-ice systems in accordance with Chapter 9 of the MU2 Maintenance Manual.\n\n \n\nCompliance: At each 100 hour maintenance interval.\n\n \n\nBackground:  A recent accident investigation revealed that ice accumulation may have been a contributing factor. A surveillance of the M2 fleet revealed an unacceptably high incidence of anti-ice and de-ice systems unserviceability.\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\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific technical issue (anti-ice/de-ice system failures) on a specific aircraft model. It has not expanded beyond its original purpose."},"complexity_factors":["Single, unambiguous requirement (operational check of specified systems)","No defined terms section","No cross-references to other legislation (only references aircraft maintenance manual)","Simple, fixed compliance interval (100 hours)","No conditional logic, exceptions, or nested provisions","Extremely 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 for **Mitsubishi MU-2 aircraft**.\n\n**What it does:**\n- Requires owners/operators to **test the anti-ice and de-ice systems** on both the airframe (the plane's body) and engines\n- The check must follow the specific instructions in **Chapter 9 of the MU-2 Maintenance Manual**\n\n**Who it affects:**\n- Anyone who owns, operates, or maintains **Mitsubishi MU-2 model aircraft** in Australia\n\n**Why it matters:**\n- **Ice buildup on aircraft is extremely dangerous** — it disrupts airflow over wings, reduces lift, and can cause crashes\n- This directive was issued after an accident investigation found ice may have contributed to a crash\n- Fleet-wide inspections also found that **too many of these planes had faulty anti-ice/de-ice systems** — meaning they couldn't safely fly in icing conditions\n\n**When you must comply:**\n- **Every 100 hours of flight time** (during regular maintenance checks)\n\nThis is a **life-safety measure** designed to prevent crashes caused by ice accumulation."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD applies only to Model MU-2 and requires operational checks of anti-ice and de-ice systems at each 100-hour maintenance interval per Chapter 9 of the MU-2 Maintenance Manual (Applicability; Requirement; Compliance). The stated background explains the reason for the requirement (Background). The instrument’s scope, as written, aligns with that stated purpose and does not indicate any change in scope from the stated intent."},"complexity_factors":["Narrow applicability: limited to Mitsubishi Model MU-2 (Applicability).","Simple, single technical requirement: one operational check specified (Requirement).","Fixed compliance interval: every 100 hours, which is straightforward to schedule (Compliance).","Procedural reliance on an external document (Chapter 9 of the MU-2 Maintenance Manual) creates dependency and potential ambiguity about exact steps (Requirement).","No enforcement, certification or remedial process detailed in the AD text, leaving operational monitoring and consequences unspecified (AD text lacks enforcement detail)."],"plain_english_summary":"The AD requires owners/operators and maintenance organisations of Mitsubishi MU-2 aeroplanes to perform an operational check of airframe and engine anti-ice/de-ice systems at every 100‑hour maintenance interval, using procedures in Chapter 9 of the MU‑2 Maintenance Manual.  \n\nIssued after an accident investigation and surveillance showing ice buildup and frequent unserviceability, it drives routine detection and repair, adds recurring inspection and repair costs, and creates dependence on the referenced manual for procedural detail."}},"importantCases":[],"_links":{"self":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems","history":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems/history","analysis":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems/analysis","conflicts":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems/conflicts","importantCases":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems/important-cases","documents":"/api/acts/ad-mu-2-46-anti-ice-and-de-ice-systems/documents"}}