{"id":"F2006B07560","name":"AD/VAT/27 - Crankcase Breather Aerobatic Oil Trap - Removal","slug":"ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50154,"registerId":"commonwealth-F2006B07560-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/VAT/27 - Crankcase Breather Aerobatic Oil Trap - Removal","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)  Victa and A.E.S.L. Airtourer Series Aeroplanes\n\n \n\nAD/VAT/27 Crankcase Breather Aerobatic Oil Trap - Removal 11/66\n\nApplicability: Victa Airtourer 100 fitted with Mod. No. B199. Document:  Victa SB No. 63.\n\nCompliance: Within 50 hours time in service, after 6 December 1966.\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\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, single-issue Airworthiness Directive from 1966 with a tightly scoped technical purpose. It has not expanded beyond its original intent of addressing a specific engine component issue on a specific aircraft variant."},"complexity_factors":["Extremely short document (single page)","Only 4 defined elements: aircraft model, modification number, service bulletin reference, and compliance timeframe","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Simple conditional logic: if you have this specific aircraft with this specific modification, you must do this specific action by this deadline","No nested exceptions or complex definitional sections"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for a specific type of light aircraft.\n\n**What it does:**\nOrders owners and operators of **Victa Airtourer 100** aeroplanes (fitted with a specific modification, Mod. No. B199) to **remove the crankcase breather aerobatic oil trap** from their aircraft engines.\n\n**Who it affects:**\n- Owners and operators of Victa Airtourer 100 aircraft with Mod. No. B199 installed\n- Maintenance engineers working on these aircraft\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety instructions. This one addresses a specific technical issue with an engine component (the oil trap) that was apparently causing problems during aerobatic manoeuvres. The reference to \"Victa SB No. 63\" suggests this directive implements a manufacturer's service bulletin.\n\n**Compliance deadline:**\nThe work must be done within **50 hours of flying time** after 6 December 1966.\n\n**Key point:** This is a historical directive from 1966 dealing with a very specific technical modification to a particular aircraft model."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The text specifies a single, narrow scope: Victa Airtourer 100 aircraft fitted with Modification No. B199 must have the specified part removed within 50 hours time in service after 6 December 1966, using Victa Service Bulletin No. 63. The AD text contains no indication that the scope has been broadened, narrowed, or otherwise altered from what it sets out here."},"complexity_factors":["Very narrow applicability: single aircraft model and a single modification number (Victa Airtourer 100 with Mod. No. B199). (Applicability)","Single, simple mandated action: removal of one component according to a cited service bulletin. (Title; Document: Victa SB No. 63)","Fixed, short compliance window tied to time-in-service accounting (50 hours TIS after 6 December 1966) which can create operational scheduling questions and record-keeping needs. (Compliance)","Reliance on an external technical document (Victa SB No. 63) for implementation details—interpretation of the AD depends on that SB. (Document: Victa SB No. 63)","Potential practical ambiguity about identification of Mod. No. B199 in records or on the aircraft, which may require inspections. (Applicability)"],"plain_english_summary":"This airworthiness directive mandates removal of a crankcase breather aerobatic oil trap from Victa Airtourer 100 aircraft fitted with Modification No. B199, using Victa Service Bulletin No. 63 for procedure. \n\nIt affects owners, operators, and maintenance organisations of those aircraft, who must arrange removal within 50 hours TIS after 6 December 1966—costs and downtime are the operator’s responsibility."}},"importantCases":[],"_links":{"self":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal","history":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal/history","analysis":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal/analysis","conflicts":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal/conflicts","importantCases":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal/important-cases","documents":"/api/acts/ad-vat-27-crankcase-breather-aerobatic-oil-trap-removal/documents"}}