{"id":"F2006B09313","name":"AD/EC 120/7 Amdt 1 - Horizontal Situation Indicator","slug":"ad-ec-120-7-amdt-1-horizontal-situation-indicator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53435,"registerId":"commonwealth-F2006B09313-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EC 120/7 Amdt 1 - Horizontal Situation Indicator","content":"![](image.001.png)\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/EC 120/7 and issues the following 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 EC 120 Series Helicopters\n\nAD/EC 120/7\n\nAmdt 1\n\n  \nHorizontal Situation Indicator 5/2004\n\nApplicability: EC 120 Versions B helicopters equipped with Bendix/King KI 525A Horizontal Situation Indicator (HSI).\n\nRequirement: 1. Check the part number (P/N) of the KI 525A HSI installed on the helicopter.\n\nInitially, no further action is necessary if the P/N is not 066-3046-07.\n\n    2. If the P/N is 066-3046-07, modify the HSI installation in accordance with Eurocopter Alert Telex 34A006 paragraph 2.A.1, for helicopters with the HSI connected to a single navigation system, or paragraph 2.A.2, for helicopters with the HSI connected to at least two navigation systems.\n\nNote 1: Modification in accordance with Eurocopter Alert Service Bulletin (ASB) 34A006 is considered acceptable for compliance with Requirement 2.\n\n    3. Before installing a KI 525A HSI P/N 066-3046-07 in place of a KI 525A HSI with P/Ns 066-3046-00, -01, -04 or -05 ensure that the HSI installation is modified in accordance with Requirement 2.\n\nNote 2: DGAC AD F-2002-282-009 R1 refers.\n\nCompliance: For Requirement 1 \\- Remains unchanged as ‘Either within 100 hours time in service after the effective date of the original issue of this Directive or before 10 August 2003, whichever occurs first’.\n\nFor Requirement 2 \\- Before further flight after the Requirement 1 check. For Requirement 3 - As of the effective date of this Amendment.\n\nThis Amendment becomes effective on 13 May 2004.\n\nBackground: Eurocopter has advised the French Direction Générale de l’Aviation Civile that KI 525A HSIs P/N 066-3046-07 may have been incorrectly installed on some helicopters. The incorrect installation may result in navigation errors.\n\nThe original issue of this Directive introduced measures to ensure that the affected HSIs were correctly installed.\n\nEurocopter EC 120 Series Helicopters\n\nAD/EC 120/7 Amdt 1 (continued)\n\nThis Amendment contains some minor editorial amendments, together with allowing credit for modifications carried out in accordance with the ASB and introduces measures to ensure that the helicopter is modified prior to the installation of a\n\nKI 525A HSI P/N 066-3046-07.\n\nThe original issue of this Airworthiness Directive became effective on 5 June 2002.\n\n![Signature of James Coyne, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 2 April 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 21 April 2004.","sortOrder":0}],"analysis":{"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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment refines the original AD by explicitly allowing credit for modifications carried out per Eurocopter ASB 34A006 (Note 1) and by adding a pre-installation requirement that a KI 525A HSI P/N 066-3046-07 must be modified before installation (Requirement 3). The underlying safety objective—ensure correct HSI installation to avoid navigation errors—remains unchanged (Background), but the amendment adds procedural detail and compliance-crediting."},"complexity_factors":["Limited technical scope: targets a single helicopter model (EC 120 B) with a specific HSI unit (KI 525A) and a single suspect P/N (066-3046-07) (Applicability; Requirement 1 & 3).","Dependence on external manufacturer documents for corrective steps (Eurocopter Alert Telex 34A006 and ASB 34A006) — operators must follow those instructions to comply (Requirement 2; Note 1).","Urgent compliance timing: initial P/N check has a set time window and required modification is 'before further flight' after the check (Compliance).","Administrative linkage to prior regulatory action: this amendment revokes the original AD and refers to the DGAC AD, so operators must reconcile historical compliance records (opening paragraph; Background; Note 2).","Credit mechanism introduced: allows prior work done to ASB standard to count for compliance, creating an evidentiary/record-keeping element (Note 1).","Operational constraint on spare parts/installation: prohibits installing the suspect P/N without prior modification, affecting maintenance/parts processes (Requirement 3)."],"plain_english_summary":"This directive requires owners/operators of Eurocopter EC 120B helicopters fitted with Bendix/King KI 525A horizontal situation indicators (HSIs) to check the HSI part number and, if it is P/N 066-3046-07, modify the installation per Eurocopter instructions before further flight; it also bars installing that P/N unless the modification is done first. CASA says the measure corrects incorrect installations that can cause navigation errors; compliance imposes inspection and modification time and cost on affected operators."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Amendment 1 remains tightly focused on the original purpose — ensuring correct installation of the KI 525A HSI part number 066-3046-07. The amendment makes only minor editorial changes, adds credit for modifications done via an Alert Service Bulletin (alternative compliance path), and closes a loophole by requiring modification before installation of the affected part. The scope has not expanded beyond the specific unsafe condition originally identified."},"complexity_factors":["Short, single-purpose document (3 requirements only)","Minimal defined terms (only standard aviation abbreviations like P/N, HSI, ASB)","Clear conditional logic (if/then structure in Requirements 1-2)","Simple cross-reference to external technical document (Eurocopter Alert Telex 34A006)","Straightforward compliance dates with specific alternatives","No nested exceptions or complex interpretive provisions"],"plain_english_summary":"This CASA Airworthiness Directive targets Eurocopter EC 120B helicopters fitted with the Bendix/King KI 525A HSI (PN 066-3046-07). It warns that some units may be incorrectly installed, risking navigation errors.\n\nAffected operators must check for the part and carry out Eurocopter’s required installation modification (and apply it before using that part as a replacement). The fix prevents potentially hazardous misleading heading/navigation indications."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator","history":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator/history","analysis":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator/analysis","conflicts":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator/conflicts","importantCases":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator/important-cases","documents":"/api/acts/ad-ec-120-7-amdt-1-horizontal-situation-indicator/documents"}}