{"id":"F2006B06672","name":"AD/ROTAX/6 - Camshaft Hardness Check","slug":"ad-rotax-6-camshaft-hardness-check","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48652,"registerId":"commonwealth-F2006B06672-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ROTAX/6 - Camshaft Hardness Check","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nRotax Piston Engines\n\nAD/ROTAX/6 Camshaft Hardness Check 7/97 DM\n\nApplicability: 1. Rotax 912 A-Series piston engines, S/N 4,380.661 up to S/N 4,380.701.\n\n2. Rotax 912UL-Series piston engines, S/N 4,153.383 up to 4,153.500 and S/N 4,400.001 up to S/N 4,400.031.\n\nRequirement: Inspection as prescribed in Bombardier Rotax Technical Bulletin 912-18 to be carried out. There are three steps to the Rotax directive, viz:\n\nStep 1. Inspection of engine oil filter and magnetic drain plug before next flight.\n\nAbnormal results of this inspection will require an engine removal and return to Rotax for repair. If inspection satisfactory, proceed to Step 2.\n\nStep 2. Within 100 operating hours after Step 1, measure camshaft hardness. If satisfactory, engine is clear of further action and normal operations may resume. If not satisfactory, repeat Step 1 every 100 operating hours until 600 operating hours reached and then take Step 3.\n\nStep 3. Return engine to Rotax agent for replacement of the defective camshaft.\n\nCompliance: Step 1: Before next flight and every 100 hrs after Step 2.\n\nStep 2: 100 operating hours after Step 1.\n\nStep 3: 600 hrs after Step 2.\n\nThis Airworthiness Directive becomes effective on 30 April 1997.\n\nBackground: Following an investigation into a report of unusual wear on a Rotax 912 camshaft, it was discovered that a batch of camshafts had been subject to deviations in material hardness during manufacture. This directive identifies the suspect engines by serial number and mandates inspection to identify defective camshafts, action to monitor in- service wear, and action to remove defective camshafts from service.","sortOrder":0}],"analysis":{"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"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive targets a specific batch of Rotax 912 engines identified by serial number to detect and remove camshafts with manufacturing hardness deviations. The instrument confines action to those serial numbers and prescribes inspection, monitoring and replacement; there is no indication in the text that the scope was broadened beyond that original batch or intent."},"complexity_factors":["Narrow applicability defined by precise engine serial numbers (Applicability).","Three-step procedural regime with conditional progression (Requirement: Step 1–3).","Time- and usage-based compliance intervals (before next flight, every 100 operating hours, 600 operating hours) (Compliance).","Technical measurement requirement (camshaft hardness measurement) relying on Bombardier Rotax Technical Bulletin 912‑18 (Requirement).","Decision points requiring judgement about 'abnormal' inspection results that trigger engine removal and return to manufacturer (Requirement Step 1).","Operational impacts: recurring inspections create downtime and maintenance scheduling burdens (Compliance).","Economic allocation: owners/operators pay for inspections, testing, removal and repair; replacement performed by Rotax agent (Requirement/Compliance).","Traceability and enforcement hinge on correct identification of serial numbers and adherence to bulletin procedures (Applicability/Requirement)."],"plain_english_summary":"Mandates that owners/operators of specified Rotax 912 engines (listed by serial number) follow a three-step maintenance program: inspect the oil filter and magnetic drain plug before next flight, measure camshaft hardness within 100 operating hours, then, after up to 600 hours of monitoring, return engines with defective camshafts to a Rotax agent for replacement (per Bombardier Rotax Technical Bulletin 912‑18). Operators bear inspection, testing and repair costs; abnormal findings trigger engine removal, recurring 100‑hour checks and scheduled compliance obligations that can cause downtime."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific manufacturing defect in identified engine serial numbers. The scope remains precisely limited to the original safety issue — camshaft hardness deviations in specific Rotax 912 engine batches. No scope creep is evident."},"complexity_factors":["Short, single-purpose directive (approximately 250 words)","Only 3 defined serial number ranges for applicability","Clear three-step sequential process with explicit timeframes","Minimal cross-referencing (only references one external technical bulletin)","No nested exceptions or conditional logic beyond simple if/then branches","Plain language structure with 'Applicability', 'Requirement', 'Compliance', and 'Background' sections"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections, testing, and eventual camshaft replacement for certain Rotax 912 piston engines (specific serial ranges) after a batch of camshafts was found with incorrect material hardness. It requires immediate oil-filter/magnetic-plug checks, a hardness verification within a set hours window, and removal/replacement of defective camshafts to prevent abnormal wear and potential in‑flight engine failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rotax-6-camshaft-hardness-check","history":"/api/acts/ad-rotax-6-camshaft-hardness-check/history","analysis":"/api/acts/ad-rotax-6-camshaft-hardness-check/analysis","conflicts":"/api/acts/ad-rotax-6-camshaft-hardness-check/conflicts","importantCases":"/api/acts/ad-rotax-6-camshaft-hardness-check/important-cases","documents":"/api/acts/ad-rotax-6-camshaft-hardness-check/documents"}}