{"id":"F2006B10628","name":"AD/HU 269/68 Amdt 1 - Lower Pulley Bearings and Housings - Inspection","slug":"ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116520,"registerId":"commonwealth-F2006B10628-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 269/68 Amdt 1 - Lower Pulley Bearings and Housings - Inspection","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nSchweizer (Hughes) 269 Series Helicopters\n\nAD/HU 269/68\n\nAmdt 1\n\n  \nLower Pulley Bearings and Housings \\- Inspection 10/93\n\nApplicability: All model 269A, 269A-1, 269B, 269C and TH-55A helicopters.\n\nRequirement: 1. Inspect all lower pulley bearings P/N 269A5050-57 or 269A5050-80 in accordance with Part 1 of Hughes SIN N-146.2 or Part III of Hughes SIN N-164.\n\n    2. Retire from service all P/N 269A5050-57 or \\-80 bearings.\n\n    3. For helicopters equipped with sheet metal bearing straps P/N 269A5463, action in accordance with Part 1 of Hughes SIN N-146.2.\n\n    4. For helicopters equipped with machined lower pulley bearing caps that are part of a 269A5573-11 “H” frame assembly inspect in accordance with Part 1 of Hughes SIN N-164.\n\nNote: FAA AD 80-02-14 refers to initial issue of this directive which referred to \\-57 bearings only.\n\nCompliance: 1. Unless previously actioned in accordance with the requirement document, inspect within 100 hours time in service from 17 September 1993. Thereafter, reinspect all bearings at intervals not exceeding 300 hours time in service.\n\n    2. Replace all bearings that have exceeded 1,700 hours time in service within 100 hours time in service from 17 September 1993. Bearings that have not exceeded 1,700 hours time in service by 17 September 1993, must be replaced at 1,800 hours time in service. Thereafter, replace bearings at intervals not exceeding 1,800 hours time in service.\n\n    3. Unless previously carried out inspect within 50 hours time in service from 17 September 1993.\n\n    4. Unless previously carried out inspect within 50 hours time in service from 17 September 1993.\n\nBackground: The manufacturer advises that discrepancies in the installation of lower coupling shaft bearings in the “H” frame could have an adverse effect on the life of the bearing.\n\nThis amendment includes the \\-80 bearing and adds a repetitive inspection requirement.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment expands scope by adding the -80 bearing part number and introducing a repetitive inspection requirement. It thereby increases the set of covered parts and imposes ongoing inspection and replacement cycles on operators, raising their compliance and maintenance burden. The amendment retains reliance on Hughes service notices for inspection procedure."},"complexity_factors":["Multiple part numbers referenced (e.g. -57 and -80 bearings) creating part-tracking burdens","Several different compliance timeframes (initial inspections, repetitive inspections, retirement and replacement hours: 50, 100, 300, 1,700/1,800 hours)","Different inspection actions depending on configuration (sheet-metal bearing straps vs machined 'H' frame caps)","Dependence on external manufacturer Service Information Notices (SIN N-146.2 and SIN N-164) for procedural detail","Retroactive/start date specificity (compliance measured from 17 September 1993) requiring historical log checks","Mandatory retirement/replace actions increase direct maintenance costs and logistical planning for operators"],"plain_english_summary":"Requires operators of Schweizer/Hughes 269-series helicopters to inspect, retire and replace specified lower pulley bearings and to inspect related housings/caps using the manufacturer’s service instructions. It sets initial and recurring inspection intervals and specific retirement/replacement hours measured from 17 September 1993. Operators pay for inspections and replacements; the Civil Aviation Safety Authority enforces compliance. The rule relies on external Hughes Service Information Notices, creating procedural and record-keeping obligations for operators."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment expanded the original 1980 directive (which only covered -57 bearings) to also include -80 bearings, and added new repetitive inspection requirements that weren't in the original. The scope grew from a one-time inspection to an ongoing maintenance obligation with multiple inspection tracks."},"complexity_factors":["Multiple part numbers and aircraft models in applicability section","Four distinct compliance deadlines with different hour thresholds (50 vs 100 hours)","Two different hour limits for replacement (1,700 vs 1,800 hours time in service)","Cross-references to external manufacturer documents (Hughes Service Information Notices N-146.2 and N-164) without reproducing their content","Conditional logic based on previous compliance ('unless previously actioned') and equipment configuration (sheet metal straps vs machined caps)","Nested timing requirements (initial inspection + repetitive intervals)"],"plain_english_summary":"This Airworthiness Directive requires operators of Schweizer (Hughes) 269 series helicopters (269A, 269A‑1, 269B, 269C, TH‑55A) to inspect and replace certain lower pulley bearings—removing -57 and -80 bearings from service—because installation issues can cause premature, unexpected failure. It adds recurring inspection and replacement timing to catch worn bearings before they cause in‑flight safety problems."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection","history":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection/history","analysis":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection/analysis","conflicts":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection/conflicts","importantCases":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection/important-cases","documents":"/api/acts/ad-hu-269-68-amdt-1-lower-pulley-bearings-and-housings-inspection/documents"}}