{"id":"F2006B10886","name":"AD/JETSTREAM/19 - Cracking of MLG Cylinder Upper Attach Lug","slug":"ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56414,"registerId":"commonwealth-F2006B10886-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JETSTREAM/19 - Cracking of MLG Cylinder Upper Attach Lug","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)  British Aerospace BAe 3100 (Jetstream) Series Aeroplanes\n\n \n\n# AD/JETSTREAM/19 Cracking of MLG Cylinder Upper Attach Lug\n\nApplicability: As listed in the requirement document.\n\n \n\nRequirement: Action in accordance with British Aerospace SB 32-JA860812. Compliance:  In accordance with the requirement document.\n\n# 5/87\n\nBackground:  During fatigue testing of the main landing gear a crack occurred in the cylinder near the upper toggle attachment lug.\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":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating inspection/repair of the MLG cylinder cracking issue identified in fatigue testing."},"complexity_factors":["Extremely short document (under 200 words)","No defined terms section — relies entirely on external references","Single operational requirement with no conditional logic or exceptions","Cross-references only to external manufacturer document (Service Bulletin) and unspecified 'requirement document'","No procedural steps, penalties, or enforcement mechanisms detailed within the instrument itself"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) for a specific aircraft type.\n\n**What it does:**\n- Orders owners and operators of **British Aerospace BAe 3100 (Jetstream) series aeroplanes** to inspect and repair a specific safety defect in the main landing gear.\n- The defect involves **cracking in the main landing gear cylinder near the upper attachment lug** — a critical structural component that holds the wheels to the aircraft.\n\n**Why it matters:**\n- This crack was discovered during **fatigue testing** (simulated repeated stress over time), meaning it could develop in real aircraft as they age and accumulate flight cycles.\n- If left unchecked, this crack could cause **landing gear failure** — potentially catastrophic during takeoff or landing.\n\n**What must be done:**\n- Aircraft operators must follow the instructions in **British Aerospace Service Bulletin SB 32-JA860812** (the manufacturer's official repair/inspection guide).\n- The exact deadlines and methods are set out in a separate \"requirement document\" referenced but not included here.\n\n**Who it affects:**\n- Airlines, charter operators, and private owners flying Jetstream 31 or 41 aircraft in Australia.\n- Maintenance engineers responsible for keeping these aircraft airworthy."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The AD itself does not state any change of scope from an earlier instrument; applicability and compliance are set by an external requirement document and the referenced British Aerospace service bulletin. No prior version or original-intent statement is provided in this text, so a change from original intent cannot be demonstrated from the instrument alone."},"complexity_factors":["Reference to an external manufacturer service bulletin (British Aerospace SB 32-JA860812) for the mandatory technical actions (Requirement).","Applicability is not stated in the AD itself but delegated to a separate requirement document (Applicability: \"As listed in the requirement document.\"), requiring users to locate and consult that document.","Compliance timing and procedural detail are likewise delegated to the requirement document (Compliance: \"In accordance with the requirement document.\"), creating potential administrative ambiguity.","Technical subject-matter involves fatigue cracking of a main landing gear component (Background), which requires specialised maintenance skills and parts.","The AD is short and prescriptive in reference but relies on multiple external documents, increasing implementation coordination complexity."],"plain_english_summary":"This AD (AD/JETSTREAM/19) requires operators of the BAe 3100 (Jetstream) aircraft listed in the requirement document to carry out the inspection and repair actions in British Aerospace SB 32‑JA860812 after fatigue testing revealed a crack in the main landing‑gear cylinder near the upper toggle attachment lug.\n\nAffected operators or their maintenance organisations must consult the requirement document and service bulletin for exact applicability, timing and technical steps, and will bear the parts, labour and downtime costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug","history":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug/history","analysis":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug/analysis","conflicts":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug/conflicts","importantCases":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug/important-cases","documents":"/api/acts/ad-jetstream-19-cracking-of-mlg-cylinder-upper-attach-lug/documents"}}