{"id":"F2006B01894","name":"AD/A320/149 - Inertial Reference Systems","slug":"ad-a320-149-inertial-reference-systems","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41090,"registerId":"commonwealth-F2006B01894-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/A320/149 Inertial Reference Systems 9","sectionType":"part","heading":"AD/A320/149 Inertial Reference Systems 9/2003","content":"# AD/A320/149 Inertial Reference Systems 9/2003\n\nDM\n\nApplicability: All Model A319, A320 and A321 series aeroplanes, all manufacturing serial numbers (MSN) equipped with Honeywell inertial reference system (IRS) having the following part numbers (P/N) but without Airbus Industrie modification 30652, 30941 or 30942 incorporated:","sortOrder":1}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original scope as a targeted safety order for specific aircraft configurations. It has not expanded beyond its purpose of addressing unsafe conditions in Honeywell IRS units on A320 family aircraft."},"complexity_factors":["Short, single-purpose document (approximately 1-2 pages in full form)","Limited defined terms (primarily 'IRS', 'P/N', 'MSN', 'CASA', 'CASR')","Straightforward conditional logic: applicability = (specific aircraft models) AND (specific Honeywell IRS part numbers) AND (NOT having specific modifications)","No nested exceptions or cross-references to other legislation beyond the enabling regulation (CASR 1998, subregulation 39.1(1))","Standardised AD format with clear section headers (Applicability, Requirement, Compliance, Background)","Technical aviation terminology assumes operator familiarity but is standard for the industry"],"plain_english_summary":"Australia's aviation safety regulator (CASA) has issued a mandatory safety order for certain Airbus A319/A320/A321 aircraft fitted with specific Honeywell inertial reference/navigation systems that have not received particular Airbus modifications.  \n\nOperators must inspect, modify or replace the affected Inertial Reference Systems by the required deadline to address a potentially unsafe navigation/fault condition; non‑compliance grounds suspension of operations and risks flight safety."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"Based solely on the supplied text, the AD's scope targets all A319/A320/A321 MSNs equipped with specified Honeywell IRS part numbers but lacking Airbus modifications 30652, 30941 or 30942. The document shows no indication that the applicability or fundamental scope has been altered from its stated purpose; no amendment history or prior scope is provided in the excerpt to indicate a change."},"complexity_factors":["Broad fleet applicability: covers all A319/A320/A321 manufacturing serial numbers (MSN) meeting the part-number condition, increasing the number of affected operators (Applicability paragraph).","Conditional scope based on incorporation of specific Airbus modifications (30652, 30941, 30942) — requires tracing modification status in maintenance records (Applicability paragraph).","Technical variability of affected parts: multiple Honeywell IRS part-numbers are listed (P/N list referenced in Applicability), creating heterogeneity in required work and parts supply.","Operational impact and scheduling: required actions and timing are set in the AD's Requirement and Compliance sections, which impose aircraft downtime and maintenance planning burdens (Requirement/Compliance sections referenced in header).","Delegated regulatory discretion: the AD is issued by a CASA delegate under subregulation 39.1(1) of CASR 1998, reflecting administrative discretion in defining corrective action (header reference).","Compliance cost allocation: operators and maintenance organisations carry costs of inspections/modifications and record searches (Requirement/Compliance/Applicability references).","Information gap in supplied text: the specific corrective actions, compliance intervals and affected part-numbers are not included in the excerpt, increasing interpretive and implementation effort for stakeholders (absence of Requirement/Compliance detail in provided text)."],"plain_english_summary":"**Airworthiness Directive (AD/A320/149)** requires inspection and/or modification of specified Honeywell inertial reference systems on Airbus A319, A320 and A321 aeroplanes that do not have Airbus modification 30652, 30941 or 30942, to address an identified unsafe condition. It obliges aircraft operators and maintenance organisations to perform the actions and meet the timing set out in the AD's Requirement and Compliance sections, issued under subregulation 39.1(1) of CASR 1998."}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-149-inertial-reference-systems","history":"/api/acts/ad-a320-149-inertial-reference-systems/history","analysis":"/api/acts/ad-a320-149-inertial-reference-systems/analysis","conflicts":"/api/acts/ad-a320-149-inertial-reference-systems/conflicts","importantCases":"/api/acts/ad-a320-149-inertial-reference-systems/important-cases","documents":"/api/acts/ad-a320-149-inertial-reference-systems/documents"}}