{"id":"F2007L01590","name":"AD/SA 315/18 - Main Gearbox Oil Acidity","slug":"ad-sa-315-18-main-gearbox-oil-acidity","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":66145,"registerId":"commonwealth-F2007L01590-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Eurocopter SA 315 (Lama) Series Helicopt","sectionType":"division","heading":"Eurocopter SA 315 (Lama) Series Helicopters","content":"### Eurocopter SA 315 (Lama) Series Helicopters\n\n| AD/SA 315/18 | Main Gearbox Oil Acidity | 7/2007 |\n| ------------ | ------------------------ | ------ |\n\n| Applicability: | Eurocopter SA 315B helicopters.                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. When checking for correct oil level and condition of the magnetic plug on the MGB, ascertain that the oil is not cloudy, excessively blackened or has any abnormal smell.2. If any of the conditions above are detected, inspect the internal condition of the MGB though the filling and drain holes in accordance with AEROSPATIALE Service Bulletin LAMA No. 01.08.If the internal protection on the MGB is affected remove the MGB for repair.Note: DGAC AD 74-79-6 dated 4 July 1974 refers. |\n| Compliance:    | 1. During the daily inspection.2. Before further flight after the effective date of this AD.                                                                                                                                                                                                                                                                                                                                                                                                         |\n|                | This Airworthiness Directive becomes effective on 5 July 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                       |\n| Background:    | Abnormal conditions such as cloudiness colour or smell can indicate excessive acidity of the oil in the MGB. This condition if not corrected can lead to failure of the MGB.                                                                                                                                                                                                                                                                                                                         |\n\n![](image.001.png)  \nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n15 May 2007","sortOrder":0},{"sectionNumber":"AD/SA 315/18","sectionType":"part","heading":"AD/SA 315/18","content":"## AD/SA 315/18","sortOrder":1},{"sectionNumber":"Main Gearbox Oil Acidity","sectionType":"part","heading":"Main Gearbox Oil Acidity","content":"## Main Gearbox Oil Acidity","sortOrder":2},{"sectionNumber":"7/2007","sectionType":"part","heading":"7/2007","content":"## 7/2007","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument, as presented, does not change scope from its stated purpose: it applies to Eurocopter SA 315B helicopters and imposes inspection and repair obligations to address oil acidity risks. No expansion to other models, additional regulatory powers, or retrospective changes are evident in the text supplied."},"complexity_factors":["Limited applicability: only Eurocopter SA 315B (Lama) helicopters (Applicability).","Simple, prescriptive checks: visual and olfactory oil checks (cloudiness, excessive blackening, abnormal smell) performed during daily inspection (Requirement 1; Compliance 1).","Clear escalation path: inspect internally via fill/drain holes per AEROSPATIALE Service Bulletin LAMA No. 01.08, then remove MGB for repair if internal protection is affected (Requirement 2).","Subjective assessment element: terms like 'cloudy', 'excessively blackened' and 'abnormal smell' require operator judgment (Requirement 1).","Dependence on external document: inspection procedure delegates technical detail to a Service Bulletin (Requirement 2).","Operational burden: daily checks plus inspection before further flight if issue found; potential downtime and repair costs for removal (Compliance).","Enforcement and authority: issued by the Civil Aviation Safety Authority delegate, effective 5 July 2007 (signature/effective date)."],"plain_english_summary":"This Airworthiness Directive requires operators of Eurocopter SA 315B (Lama) helicopters to check the main gearbox (MGB) oil daily for cloudiness, excessive darkening or abnormal smell. If any of those signs are found, the internal condition must be inspected via the fill and drain holes following AEROSPATIALE Service Bulletin LAMA No. 01.08, and the MGB removed for repair if the internal protection is affected. The AD cites excessive oil acidity as a risk to MGB integrity; compliance imposes inspection, possible repair and downtime costs on operators and takes effect 5 July 2007."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — a targeted safety directive for a specific helicopter model addressing a specific mechanical failure mode (MGB oil acidity). There is no evidence of scope creep; it remains a discrete maintenance requirement without expansion into broader operational or certification matters."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 1 defined term implicitly used (MGB — Main Gearbox)","No cross-references to other legislation or complex conditional logic","Simple two-step compliance structure: (1) daily visual/smell check, (2) conditional inspection/repair if problems found","Single applicability criterion (specific helicopter model)","Straightforward temporal compliance: 'during daily inspection' and 'before further flight'"],"plain_english_summary":"This CASA Airworthiness Directive mandates owners/operators of Eurocopter SA 315B (Lama) helicopters to perform daily MGB oil-level and magnetic-plug checks for cloudy oil, excessively black oil, or abnormal smell. \n\nIf any of those signs appear, the gearbox interior must be inspected via fill/drain holes per AEROSPATIALE Service Bulletin LAMA No. 01.08 and, if damaged, the main gearbox removed and repaired — to prevent acidic-oil–related gearbox failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity","history":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity/history","analysis":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity/analysis","conflicts":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity/conflicts","importantCases":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity/important-cases","documents":"/api/acts/ad-sa-315-18-main-gearbox-oil-acidity/documents"}}