{"id":"F2006B09846","name":"AD/F50/20 Amdt 1 - Engine Tailpipe Assembly","slug":"ad-f50-20-amdt-1-engine-tailpipe-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54901,"registerId":"commonwealth-F2006B09846-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F50/20 Amdt 1 - Engine Tailpipe Assembly","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Fokker F50 (F27 Mk 50) Series Aeroplanes\n\n \n\nAD/F50/20\n\nAmdt 1\n\n\nEngine Tailpipe Assembly 1/92\n\n \n\nApplicability: All F50 series aircraft equipped with P/N F8200-08-401 or F8200-08-403 exhaust tailpipe assemblies.\n\n \n\nRequirement: Action in accordance with the Technical Requirements of Netherlands Airworthiness Directive BLA No 89-038 Issue 2.\n\n \n\nCompliance: As detailed in the Requirement document with a revise effective date of 12 January 1992.\n\n \n\nBackground:  This Directive has been amended to reflect the revision of Netherlands Airworthiness Directive BLA No. 89-038. The revision includes additional inspection requirements for P/N F8200-08-403 tailpipes, and introduces a terminating action.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Yes. The amendment expands the directive by reflecting a revision of the Netherlands Airworthiness Directive: it adds additional inspection requirements for tailpipes with P/N F8200-08-403 and introduces a terminating action. The change therefore increases inspection obligations for that part number and creates a new one-off option to end recurring inspections. (Background; Applicability)"},"complexity_factors":["Requires compliance with an external technical document (Netherlands AD BLA No 89-038 Issue 2) rather than reproducing procedures in the instrument itself (Requirement).","Applies only to aircraft fitted with specific part numbers (P/N F8200-08-401 and P/N F8200-08-403), which narrows scope but requires fleet-level part-number checks (Applicability).","Adds additional inspection requirements for one part number (F8200-08-403), creating recurring obligations whose intervals/details are in the external document (Background).","Introduces a terminating action option that creates a choice between repeated inspections or a one-off corrective/modify action, increasing operational decision complexity (Background).","Compliance timing is tied to a revised effective date and the external document’s schedule, requiring operators to manage cross-references and scheduling (Compliance)."],"plain_english_summary":"What this amendment does, in plain terms\n\n- Mechanically, the Civil Aviation Safety Authority (CASA) amendment requires all Fokker F50 (F27 Mk 50) aircraft that have exhaust tailpipe assemblies with part number F8200-08-401 or F8200-08-403 to follow the technical instructions set out in the Netherlands Airworthiness Directive BLA No 89-038 Issue 2. The amendment adopts those technical requirements and sets compliance according to the revised effective date of 12 January 1992. (Requirement; Compliance; Applicability)\n\n- The official stated change is that the Netherlands AD was revised to add extra inspection requirements for tailpipes with P/N F8200-08-403 and to introduce a \"terminating action\" (an action that, once completed, ends the need for further repetitive inspections). The CASA amendment reflects that revision. (Background)\n\nWho is affected\n\n- Aircraft owners/operators and their maintenance organisations that operate F50 series aeroplanes fitted with tailpipe assemblies P/N F8200-08-401 or P/N F8200-08-403. (Applicability)\n\nWho pays and who decides\n\n- The direct costs (inspection labour, parts, modification work, and aircraft downtime) fall on the aircraft owner/operator and their maintenance providers because those parties must carry out the required inspections or the terminating action in order to be compliant. (Applicability; Requirement)\n\n- The regulatory decision is CASA’s: the amendment makes compliance with the Netherlands AD requirements mandatory for the specified Australian-registered aircraft. The AD references and binds operators to the technical instructions in Netherlands Airworthiness Directive BLA No 89-038 Issue 2. (Requirement)\n\nWhat behaviour changes\n\n- Operators must carry out the inspection tasks and any corrective or terminating actions described in the referenced Netherlands AD by the compliance schedule set out with the revised effective date. This will change maintenance planning (more inspections for P/N F8200-08-403 tailpipes) and may create an incentive to perform the terminating action (a one-off modification or repair) to stop recurring inspections. (Background; Compliance)\n\nOfficial purpose claim and an operational test of that claim\n\n- The amendment’s stated reason is to reflect the Netherlands AD revision which adds inspections and a terminating action for the specified tailpipes. (Background)\n\n- Testing that claim against operational consequences (based on the text): the added inspections increase recurring maintenance activity for affected tailpipes; the terminating action offers a one-off option that may substitute for repeated inspections. Both choices impose resource costs: time, parts, certified labour, and aircraft out-of-service hours. The text does not provide details of the inspection intervals, the technical content of the terminating action, or cost estimates—those are in the Netherlands AD referenced by this amendment. (Requirement; Compliance)\n\nTrade-offs, incentives and practical risks (grounded in the amendment text)\n\n- Costs and incentives: the introducing of additional inspections increases ongoing operating costs for owners of aircraft with P/N F8200-08-403. The introduction of a terminating action creates a financial and operational incentive to carry out whatever modification or repair ends recurring inspections. (Background)\n\n- Compliance burden and administrative friction: the AD requires operators to follow a technical document issued by another authority (Netherlands AD BLA No 89-038 Issue 2). That means operators must obtain, interpret, and implement an external technical document to demonstrate compliance. The CASA amendment itself does not reproduce the inspection procedures or terminating-action details; it binds operators to those external technical requirements. (Requirement; Compliance)\n\n- Implementation risk: because the amendment points to an external technical requirement, any ambiguity, parts availability issues, or unanticipated maintenance complexity within that external document could create operational or scheduling difficulties for operators. The amendment text does not resolve such risks; it only requires compliance with the external instruction. (Requirement; Compliance)\n\nEffects on market participants and maintenance providers\n\n- The immediate demand effect is concentrated on owners/operators of the specified F50 aircraft and on maintenance providers who service those tailpipe assemblies: inspections and terminating actions will require labour and possibly parts or modifications, generating business for approved maintenance organisations. (Applicability; Background)\n\n- For other market dimensions—competition, ownership, prices, or contract freedom—the text itself does not alter market rules beyond imposing a maintenance obligation on the specified aircraft. Any broader effects (for example, on parts suppliers or on aircraft resale value) depend on the technical content and cost of the inspections/terminating action in the referenced Netherlands AD, which this amendment adopts. (Requirement; Background)\n\nKey practical points for operators (text-based)\n\n- Identify whether your aircraft has tailpipe assembly P/N F8200-08-401 or F8200-08-403. If it does, obtain and follow the Technical Requirements in Netherlands AD BLA No 89-038 Issue 2. (Applicability; Requirement)\n\n- Plan for the compliance timing set by the revised effective date of 12 January 1992 and for the operational impact of inspections or any terminating action listed in the Netherlands AD. (Compliance)\n\nReferences in the instrument: Applicability; Requirement; Compliance; Background."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a routine amendment to an existing airworthiness directive. The scope remains tightly focused on Fokker F50 exhaust tailpipe assemblies. The amendment simply updates the referenced Dutch directive to a newer issue (Issue 2) and adds specific inspection requirements for one additional part number, plus a terminating action. This is standard maintenance of aviation safety requirements, not scope creep."},"complexity_factors":["Very short document (under 200 words)","Only 2 specific part numbers affected","Single requirement: comply with an external Dutch directive","No defined terms section","No nested conditional logic or exceptions","Simple structure: Applicability → Requirement → Compliance → Background"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:** It requires owners and operators of Fokker F50 aircraft to inspect or fix a specific problem with the engine exhaust tailpipe assembly (the part that channels hot exhaust gases out of the engine). \n\n**Who it affects:** Anyone operating Fokker F50 series aircraft that have specific part numbers for their exhaust tailpipes (P/N F8200-08-401 or P/N F8200-08-403).\n\n**What must be done:** Operators must follow the technical instructions set out in a Dutch airworthiness directive (Netherlands AD BLA No 89-038 Issue 2). This updated version (Amendment 1) adds extra inspection requirements for one specific tailpipe model (the -403 version) and provides a \"terminating action\" — meaning there's now a permanent fix available that ends the need for repeated inspections.\n\n**Why it matters:** Exhaust tailpipes operate under extreme heat and pressure. If they fail, it could damage the engine, reduce aircraft performance, or create fire risks. This directive ensures potential cracks or wear are caught before they become dangerous."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly","history":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly/history","analysis":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly/analysis","conflicts":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly/conflicts","importantCases":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly/important-cases","documents":"/api/acts/ad-f50-20-amdt-1-engine-tailpipe-assembly/documents"}}