{"id":"F2005L00585","name":"AD/BAe 146/105 Amdt 1 - APU - Air Inlet Duct - Modification","slug":"ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":112826,"registerId":"commonwealth-F2005L00585-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"British Aerospace BAe 146 Series Aeropla","sectionType":"division","heading":"British Aerospace BAe 146 Series Aeroplanes","content":"### British Aerospace BAe 146 Series Aeroplanes\n\n| AD/BAe 146/105 Amdt 1 | APU - Air Inlet Duct - Modification | 4/2005 |\n| --------------------- | ----------------------------------- | ------ |\n\n| Applicability: | BAe 146 and AVRO -RJ series aeroplanes as identified in the requirement document.                                                                                                                                                                                                                                                                                                |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Carry out modification per BAE Systems SB. 49-036-36019E, Rev 5, Dated 27 July 2004.Note 1: This service bulletin has been classified as mandatory by UK-CAA.Note 2: Aeroplanes that are in compliance with Rev 4 of the reference document only need to complete the additional items added by Rev 5 of the reference document.                                                 |\n| Compliance:    | Unless previously accomplished, at the next scheduled APU removal or at the next aircraft C-Check whichever is earlier after the effective date of this Directive.                                                                                                                                                                                                               |\n|                | This Amendment becomes effective on 14 April 2005.                                                                                                                                                                                                                                                                                                                               |\n| Background:    | Contamination of cabin air due to the ingestion of oil from the APU bay is found to occur on the affected aircraft. This modification provides an improved seal at the aircraft - APU interface to prevent this.Rev 5 of the reference document introduces replacement of the bellows attachment hardware.The original issue of this Directive became effective on 10 July 2003. |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n2 March 2005","sortOrder":0},{"sectionNumber":"AD/BAe 146/105 Amdt 1","sectionType":"part","heading":"AD/BAe 146/105 Amdt 1","content":"## AD/BAe 146/105 Amdt 1","sortOrder":1},{"sectionNumber":"APU - Air Inlet Duct - Modification","sectionType":"part","heading":"APU - Air Inlet Duct - Modification","content":"## APU - Air Inlet Duct - Modification","sortOrder":2},{"sectionNumber":"4/2005","sectionType":"part","heading":"4/2005","content":"## 4/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Scope was amended from the original Directive by adding replacement of the bellows attachment hardware (Rev 5) and by clarifying that aeroplanes already compliant with Rev 4 need only complete the additional items introduced by Rev 5 (Requirement; Background). Compliance timing remains linked to the next APU removal or next C‑Check (Compliance)."},"complexity_factors":["Single technical modification specified by a single service bulletin (BAE SB 49‑036‑36019E Rev 5).","Compliance timing tied to maintenance events (next APU removal or next aircraft C‑Check) rather than a calendar deadline.","Existing compliance variance: aircraft compliant with Rev 4 only must do the additional Rev 5 items (Requirement).","Includes replacement of specific hardware (bellows attachment) which may require parts availability and skilled labour (Background).","Regulatory cross‑reference: the service bulletin is classified as mandatory by UK‑CAA, creating a foreign-airworthiness linkage (Requirement).","Clear effective date and prior effective issue (effective 14 Apr 2005; original effective 10 Jul 2003) reducing ambiguity on timing."],"plain_english_summary":"This safety directive requires BAe 146 and Avro‑RJ aircraft to have the APU air inlet duct modified per BAE Systems Service Bulletin 49‑036‑36019E Rev 5 (27 July 2004). Operators must complete the work at the next scheduled APU removal or at the next aircraft C‑Check, whichever occurs first, incurring associated labour and parts costs (Compliance). Rev 5 adds replacement of the bellows attachment hardware; the modification improves the seal at the aircraft–APU interface to reduce oil ingestion into cabin air (Background)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, technical amendment to an existing Airworthiness Directive. It maintains the original safety purpose (preventing cabin air contamination) while updating the technical requirements to a newer revision of the service bulletin. The scope remains tightly focused on the specific APU modification."},"complexity_factors":["Single, specific technical requirement referencing an external service bulletin","Only one defined applicability criterion (aircraft series)","Simple compliance timeline with two alternative triggers (APU removal OR C-Check)","One conditional exception for aircraft already compliant with earlier revision","No nested definitions, cross-references to other legislation, or conditional logic beyond the basic compliance exception"],"plain_english_summary":"This Airworthiness Directive mandates operators of British Aerospace BAe 146 and AVRO RJ aircraft to modify the APU air-inlet seal to stop engine oil entering the cabin air system. Compliance must follow Service Bulletin 49-036-36019E, Revision 5.\n\nIt affects aircraft operators and maintenance organisations, is legally mandatory by the next APU removal or C‑check after 14 April 2005, and for Rev‑4-modified aircraft only the additional Rev‑5 hardware must be fitted."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification","history":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification/history","analysis":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification/analysis","conflicts":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification/conflicts","importantCases":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification/important-cases","documents":"/api/acts/ad-bae-146-105-amdt-1-apu-air-inlet-duct-modification/documents"}}