{"id":"F2006B02283","name":"AD/AL 250/72 Amdt 1 - No. 8 Bearing Oil Supply Tube","slug":"ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41513,"registerId":"commonwealth-F2006B02283-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AL 250/72 Amdt 1 - No. 8 Bearing Oil Supply Tube","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)  \nAllison Turbine Engines \\- 250 Series\n\nAD/AL 250/72\n\nAmdt 1\n\n  \nNo. 8 Bearing Oil Supply Tube 13/87 DM\n\nApplicability: Model 250-C30, \\-C30L, \\-C30M, \\-C30P, \\-C30R and \\-C30S.\n\nRequirement: 1. Inspect the No 8 bearing pressure oil tube in accordance with Allison CEB-A-72- 3165 Part I; and,\n\n    2. For operators who have previously complied with Allison CEB-A-72-3159 or actioned the original issue of this Directive, remove superseded oil tube assy P/N 23037410 and replace it with tube assy P/N 23038235 in accordance with Allison CEB-A-72-3165 Part II; or,\n\n    3. For operators who haven’t complied with Allison CEB-A- 72-3159 or actioned the original issue of this Directive, remove the No 8 bearing pressure oil tube P/N 6892825 and install new tube assy P/N 23038235 and oil fitting P/N 23035275 in accordance with Allison CEB-A-72-3165 Part III.\n\nCompliance: For Part 1: Unless already accomplished, prior to further flight after 7 September 1987 and then subsequent to the last flight of each day until modified in accordance with Part 2 or Part 3 as applicable.\n\nFor Part 2: At the earliest possible opportunity after receipt of parts but no later than 10 December 1987.\n\nFor Part 3: At the earliest possible opportunity after receipt of parts but no later than 1 July 1988.\n\nNote: Compliance with the previous issue of this Directive will require further action in accordance with Part 2.\n\nBackground: This Directive is amended to reflect Allison CEB-A-72-3165 which was issued subsequent to the cancellation of CEB-A-72-3159. SB -3159 was the Requirement Document quoted in the original issue of this Directive. “Interim” oil tube assy P/N 23037410 is now to be removed to correct a dimensional problem associated with its installation.","sortOrder":0}],"analysis":{"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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amends the original directive to reflect Allison CEB‑A‑72‑3165 and to require removal of the interim oil tube assembly P/N 23037410 because of a dimensional installation problem; thus it narrows/changes the corrective action required from the earlier issue."},"complexity_factors":["Multiple compliance pathways based on operators' prior actions (previously complied vs not) increasing decision points.","Several distinct part numbers to remove/install (P/N 6892825, 23037410, 23038235, 23035275) requiring parts sourcing and tracking.","Staged compliance timing: immediate daily inspections until modification, and two separate final replacement deadlines (10 Dec 1987; 1 Jul 1988).","Cross‑references to manufacturer documents (Allison CEB‑A‑72‑3165 Parts I–III and superseded CEB‑A‑72‑3159) for procedural detail.","Operational burden of recurring inspections (every day until modified) adds ongoing compliance cost and scheduling impact."],"plain_english_summary":"This directive requires operators of Allison 250‑C30 series turbine engines to inspect the No. 8 bearing pressure oil tube and, depending on prior compliance, remove and replace specified oil‑tube assemblies and fittings with the part numbers named in the manufacturer's service bulletin. Operators must carry out daily inspections until the engine is modified and meet set deadlines for replacement. Operators pay for inspections, parts and installation; the Civil Aviation Safety Authority mandates compliance and sets the deadlines. The amendment requires removal of an interim tube (P/N 23037410) to correct a dimensional problem."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is an amendment to an existing Airworthiness Directive (AD/AL 250/72). The scope remains tightly focused on the No. 8 bearing oil supply tube issue. The amendment simply updates the technical reference (from CEB-A-72-3159 to CEB-A-72-3165) and mandates removal of an interim repair part that proved defective. It does not expand to other engine components or models."},"complexity_factors":["Multiple compliance pathways (Part 1, 2, and 3) depending on prior maintenance history","Cross-references to external technical documents (Allison CEB-A-72-3165 Parts I, II, and III) without reproducing their content","Nested conditional logic: different actions required based on whether operator complied with superseded directive CEB-A-72-3159 or original AD issue","Specific part numbers (P/Ns) that must be tracked across three different scenarios","Dual deadlines with 'earliest possible opportunity' qualifiers plus hard dates (10 Dec 1987 and 1 July 1988)","Note creates additional obligation for operators who thought they were already compliant"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Allison 250-C30 series engines to inspect and replace a faulty No. 8 bearing oil supply tube that can cause oil starvation and engine seizure. It mandates immediate pre-flight and daily inspections until the tube is replaced.\n\nOperators who fitted the interim tube must install the redesigned tube by 10 Dec 1987; others must install the new tube and oil fitting by 1 Jul 1988 to eliminate the dimensional-fit safety risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube","history":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube/history","analysis":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube/analysis","conflicts":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube/conflicts","importantCases":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube/important-cases","documents":"/api/acts/ad-al-250-72-amdt-1-no-8-bearing-oil-supply-tube/documents"}}