{"id":"F2006B11015","name":"AD/JT9D/22 - First Stage High Pressure Turbine Airseal","slug":"ad-jt9d-22-first-stage-high-pressure-turbine-airseal","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56616,"registerId":"commonwealth-F2006B11015-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT9D/22 - First Stage High Pressure Turbine Airseal","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)  \nPratt and Whitney Turbine Engines \\- JT9D Series\n\nAD/JT9D/22 First Stage High Pressure Turbine Airseal 2/91\n\nApplicability: JT9D-3A, \\-7, \\-7A, \\-7A(SP), \\-7AH, \\-7F, \\-7H, \\-7J, \\-20, \\-20J engines fitted with P/N 797576, 797576P48, 793707 first stage high pressure turbine airseals.\n\nRequirement: 1. Replace first stage high pressure turbine airseals as listed by serial number in PWA Service Bulletin No 5873 Rev 1, Para 2, Part A.\n\n2. Inspect, first stage high pressure turbine airseals not listed by serial number in PWA Service Bulletin No 5873 Rev 1, Para 2, Part A, in accordance with PWA Service Bulletin No 5873 Rev 1, Para 2, Part B.\n\nNote: FAA AD 90-23-19 refers.\n\nCompliance: 1. At next engine shop visit regardless of planned maintenance action or reason for engine removal.\n\n2. At next access to affected parts.\n\nBackground: This Directive reflects advice of an uncontained JT9D-7R4H1 engine failure event.\n\nThe failure was attributed to cracking of an Inconel-718 material airseal. Certain lower rated JT9D models may also be fitted with the same part number airseal. This Directive requires replacement or inspection of those airseals.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original, narrow scope: addressing a specific safety defect in a specific engine part. It has not expanded beyond its original purpose of preventing uncontained engine failures due to cracked airseals."},"complexity_factors":["Single, specific technical subject matter (one engine part on specific engine models)","Only 2 operative requirements with clear alternatives (replace OR inspect)","Minimal cross-referencing (only to FAA AD 90-23-19 and one manufacturer service bulletin)","No defined terms section — uses standard aviation terminology","Straightforward compliance timeline (next maintenance event)","Short document (approximately 200 words)"],"plain_english_summary":"This safety order requires airlines and maintenance organisations to inspect or replace the first-stage high-pressure turbine airseal in certain Pratt & Whitney JT9D engines (per a manufacturer service bulletin) at the next maintenance opportunity. It targets airseals with specific serial numbers and those not on the approved list.  \n\nIt aims to prevent repeat uncontained engine failures caused by cracked Inconel-718 airseals and is enforceable by CASA, affecting operators of the listed engines."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive targets the parts and engine models implicated by the documented failure and prescribes immediate corrective action (replacement or inspection). It does not expand beyond the identified part numbers, serial numbers (per the service bulletin), or the covered JT9D variants; it implements a targeted safety corrective measure rather than broadening regulatory scope."},"complexity_factors":["Narrow technical scope: specific engine models and three part numbers specified (low breadth).","Operational timing conditionality: compliance tied to 'next engine shop visit' or 'next access' rather than a fixed calendar deadline.","Dependency on external documents: substantive procedures and serial-number lists are in PWA Service Bulletin No 5873 Rev 1 (Parts A and B) and cross‑referenced FAA AD 90‑23‑19.","Decision split: some airseals must be replaced (listed serial numbers) while others only require inspection, creating an evidentiary/record check burden.","Safety‑critical repair/inspection work requires engine shop access and technical capability, imposing practical scheduling and cost on operators.","Traceability/admin burden: operators must determine affected serial numbers and retain records to demonstrate compliance."],"plain_english_summary":"Requires operators of Pratt & Whitney JT9D engines fitted with first‑stage high‑pressure turbine airseals (P/N 797576, 797576P48, 793707) to replace airseals listed by serial number in PWA Service Bulletin No 5873 Rev 1 Part A and to inspect other such airseals per Part B of that bulletin. Compliance is at the next engine shop visit or next access to the parts; the directive follows an uncontained engine failure attributed to cracking of Inconel‑718 airseals. Operators/engine owners must perform and fund the required replacement or inspection and follow the referenced service bulletin (see FAA AD 90‑23‑19)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal","history":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal/history","analysis":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal/analysis","conflicts":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal/conflicts","importantCases":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal/important-cases","documents":"/api/acts/ad-jt9d-22-first-stage-high-pressure-turbine-airseal/documents"}}