{"id":"F2006B09394","name":"AD/ECUREUIL/91 - Air Intake Cowling","slug":"ad-ecureuil-91-air-intake-cowling","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53729,"registerId":"commonwealth-F2006B09394-current","compilationNumber":null,"startDate":"2026-04-02","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\nEurocopter AS 350 (Ecureuil) Series Helicopters","sortOrder":0},{"sectionNumber":"AD/ECUREUIL/91 Air Intake Cowling 11/200","sectionType":"part","heading":"AD/ECUREUIL/91 Air Intake Cowling 11/2003 TX","content":"# AD/ECUREUIL/91 Air Intake Cowling 11/2003 TX\n\nApplicability: Eurocopter EC 130 B4 model helicopters fitted with cowling attachment fittings P/N 350A25-0405-00, -01, -02, -03, -04 and -05.\n\nRequirement: 1. Perform a visual inspection of the two forward air intake cowling attachment fittings in accordance with the instructions contained in Section 2.B. of Eurocopter EC130 Alert Service Bulletin No. 53A004.\n\n    2. If the two forward cowling attachment fittings are neither failed nor cracked, re-inspect in accordance with the instructions contained in Section 2.B. of Eurocopter EC130 Alert Service Bulletin No. 53A004.\n\n    3. If one or both of the forward cowling attachment fittings have failed or are cracked, also check the condition the centre and aft fittings.\n\n    4. If one or more of the forward, centre or aft fittings have failed, replace them.\n\n    5. If one or more of the forward, centre or aft fittings are cracked:\n\n    (i). Replace each cracked fitting which has more than 2 cracks or any fitting in which the longest crack is more than 10mm.\n\n    (ii). Stop drill cracks in fittings which have 2 cracks or less and any fitting in which the longest crack is equal to or less than 10mm. Re-inspect in accordance with compliance 5(ii).\n\nNote: DGAC AD U2003-358(A) refers.\n\nCompliance: 1. For helicopters that have less than 100 flight hours, accomplish before 110 flight hours TTIS.\n\nFor helicopters that have accumulated 100 hours or more at the effective date of this Directive, accomplish within 10 flight hours after 18 September 2003.\n\n    2. Repeat at intervals not to exceed 110 flight hours.\n\n    3. Before further flight.","sortOrder":1}],"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":false,"description":"The AD’s scope is limited to EC130 B4 helicopters fitted with the listed cowling attachment part numbers and specifies inspection/repair/replacement actions per the Eurocopter service bulletin. There is no textual indication the AD expands beyond those helicopters or beyond the listed corrective measures; applicability and required actions remain as originally stated (Applicability; Requirement; Compliance)."},"complexity_factors":["Narrow applicability requiring matching part numbers (P/N 350A25-0405-00 through -05) (Applicability).","Mandatory reference to an external service bulletin for inspection instructions (Section 2.B. of Eurocopter EC130 Alert Service Bulletin No. 53A004) (Requirement 1).","Conditional branching based on inspection findings: re‑inspection, centre/aft checks, stop‑drilling, repair or replacement (Requirement 2–5).","Quantitative defect thresholds that determine action: more than 2 cracks or longest crack >10 mm requires replacement; ≤2 cracks and ≤10 mm allows stop‑drill and re‑inspection (Requirement 5(i)/(ii)).","Timing rules tied to total time‑in‑service (TTIS) and an effective date, plus a repeating interval (initial/compliance and Compliance 1–2).","Immediate safety mandate for failed fittings requiring action 'before further flight' (Compliance 3).","Regulatory basis cited (CASR subregulation 39.1(1)) and cross‑reference to a foreign AD (DGAC AD U2003-358(A)), which may affect interpretation and coordination (preamble/Note)."],"plain_english_summary":"This AD requires owners/operators of Eurocopter EC130 B4 helicopters fitted with specified cowling attachment fittings to inspect the two forward air‑intake cowling fittings (and centre/aft if faults are found) per Eurocopter EC130 Alert Service Bulletin No. 53A004, and to stop‑drill, repair or replace fittings that meet the AD’s crack/failure thresholds. \n\nIt sets timing rules: initial checks tied to total time‑in‑service or within 10 flight hours after 18 Sep 2003, repeat inspections every 110 flight hours, and mandatory action before further flight where failures exist. Owners/operators pay for inspections, parts and downtime."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard, targeted airworthiness directive addressing a specific unsafe condition (fatigue cracking of cowling attachment fittings). It has not expanded beyond its original safety purpose."},"complexity_factors":["Short, single-purpose directive focused on one specific mechanical issue","Clear sequential logic (inspect → assess condition → take specific action based on findings)","Only 5 defined part numbers in applicability section","Simple conditional structure with binary outcomes (failed/cracked vs. intact)","Cross-reference to only one external document (Eurocopter Alert Service Bulletin No. 53A004)","Compliance deadlines based on straightforward flight hour thresholds","No nested exceptions or complex definitional provisions"],"plain_english_summary":"Owners/operators of Eurocopter EC 130 B4 helicopters with specified air‑intake cowling attachment fittings must inspect and, where necessary, repair or replace front fittings to prevent cowling detachment in flight. Cracked or broken fittings require repair/replacement before further flight; intact fittings must be rechecked at regular intervals. The AD targets fatigue cracking that could lead to cowling loss, damage, or loss of control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-91-air-intake-cowling","history":"/api/acts/ad-ecureuil-91-air-intake-cowling/history","analysis":"/api/acts/ad-ecureuil-91-air-intake-cowling/analysis","conflicts":"/api/acts/ad-ecureuil-91-air-intake-cowling/conflicts","importantCases":"/api/acts/ad-ecureuil-91-air-intake-cowling/important-cases","documents":"/api/acts/ad-ecureuil-91-air-intake-cowling/documents"}}