{"id":"F2006B09514","name":"AD/EMB-120/27 Amdt 3 - Icing Conditions","slug":"ad-emb-120-27-amdt-3-icing-conditions","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54086,"registerId":"commonwealth-F2006B09514-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Whenever ice is detected: immediately","sectionType":"part","heading":"Whenever ice is detected: immediately","content":"# Whenever ice is detected: immediately\n\nturn deice boots on\n\n    5. Install a low speed aural/visual alarm system in the center glare shield in accordance with SB 120-30-0033 Rev 01 dated 6 September 2001, Rev 02 dated 14 September 2002 or Rev 03 dated 22 October 2001.\n\nNote 1: This system should be installed after or together with removal of the leading edge boots inflation cycle control \"light-heavy\" switch, as per Requirement 3.\n\n    6. Superseded by Requirement 13.\n\n    7. Superseded by Requirement 13.\n\n    8. Superseded by Requirement 13.\n\n    9. Superseded by Requirement 13.\n\n    10. Superseded by Requirement 13.\n    11. Superseded by Requirement 13.","sortOrder":0},{"sectionNumber":"Embraer EMB-120 (Brasilia) Series Aeropl","sectionType":"part","heading":"Embraer EMB-120 (Brasilia) Series Aeroplanes","content":"# Embraer EMB-120 (Brasilia) Series Aeroplanes\n\nAD/EMB-120/27 Amdt 3 (Continued)\n\n    12. Modify the low speed aural/visual alarm system to permit inhibition of the alarm when landing gear is down and locked or cancellation of the aural alarm by flight crew in accordance with SB 120-30-0033 Rev 03.\n    13. Remove all Aircraft Flight Manual (AFM) revisions/amendments introduced by Amendment 1 or 2 of this Directive and ensure that AFM-120/813 has Revision 70 incorporated.\n\nNote 2: Brazilian DAC AD 2001-05-02R2 Amdt 39-924 and AD 2001-0502R2 Errata refer.\n\nCompliance: Requirement 1 \\- Not applicable.\n\nRequirement 2 \\- Not applicable.\n\nRequirement 3 \\- Remains unchanged, as ‘Within 400 hours TIS or 180 days from the effective date of the original issue of this Directive whichever is later’.\n\nRequirement 4 \\- No later than 28 June 2002.\n\nRequirement 5 \\- No later than 28 June 2002\\. Requirement 6 - Not applicable.\n\nRequirement 7 - Not applicable. Requirement 8 - Not applicable. Requirement 9 - Not applicable. Requirement 10 \\- Not applicable. Requirement 11 \\- Not applicable.\n\nRequirement 12 \\- No later than 28 June 2002.\n\nRequirement 13 \\- Within seven days from the effective date of this Directive. This Amendment becomes effective on 23 May 2002.\n\nBackground: The Brazilian Departamento de Aviação Civil (DAC) received reports of loss of control events when flying in icing conditions, indicating that flight crew can misjudge both the severity of ice accretion and the need to take immediate action to prevent excessive loss of airspeed, especially when using the autopilot. The original issue of this Directive imposed operational limitations in the AFM, together with installation of placards in the cockpit, and removal of the deice boots “light- heavy” switch.","sortOrder":1}],"analysis":{"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Amendment 3 alters compliance obligations from the Directive's earlier versions by superseding several previous requirements (Requirements 6–11 noted as superseded by Requirement 13) and replacing AFM amendments introduced by Amendments 1 and 2 with a mandated incorporation of AFM-120/813 Revision 70 (Requirement 13). It also refines alarm installation/modification rules (Requirements 5 and 12). These changes adjust what operators must install, what AFM material must be retained or removed, and the applicable deadlines."},"complexity_factors":["Technical, equipment-specific mandates referencing Service Bulletin SB 120-30-0033 Rev 01/02/03 (Requirement 5 & 12) create installation conformity obligations for maintenance organisations.","Operational command to 'turn deice boots on immediately' when ice is detected places a real‑time cockpit action requirement on flight crews (opening operative text).","Modification to permit alarm inhibition when landing gear is down and locked or cancellation by crew (Requirement 12) introduces crew discretion affecting safety-critical alerts.","Multiple supersessions and non-applicability statements: Requirements 6–11 are superseded by Requirement 13, and several Requirements are listed as 'Not applicable' (compliance section), complicating which historical actions remain binding.","AFM changes: removal of AFM revisions introduced by Amendments 1 and 2 and mandatory incorporation of AFM-120/813 Revision 70 (Requirement 13) requires procedural/documentation updates and immediate compliance (within seven days).","Staggered and short compliance deadlines (e.g. 'no later than 28 June 2002', 'within 400 hours TIS or 180 days', and 'within seven days' for Requirement 13) increase planning and logistical complexity for operators.","Cross-jurisdictional references to Brazilian DAC ADs and earlier FAA ADs (Background and Note 2) add regulatory alignment considerations for international operators.","Background technical justification (reports of loss of control in icing, autopilot masking severity) ties operational and equipment measures together, increasing the need for coordinated training and maintenance changes."],"plain_english_summary":"This Airworthiness Directive for Embraer EMB-120 aircraft requires flight crews to turn the deice boots on immediately when ice is detected, mandates installation and later modification of a low‑speed aural/visual alarm per SB 120‑30‑0033, and cancels prior AFM amendments in favour of AFM‑120/813 Revision 70. It affects aircraft operators, maintainers and flight crew: operators bear the cost and scheduling burden of installations, AFM changes and training, while crews gain a procedural requirement and limited discretion to inhibit or cancel the alarm."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original directive was a straightforward safety response to icing incidents, requiring placards and operational limitations. Through three amendments, it evolved into a complex technical retrofit program involving: (1) replacement of placards with electronic warning systems, (2) multiple revisions to those systems, (3) corrections to flight manual airspeed values (160 to 140 KIAS), and (4) eventual replacement of all previous flight manual amendments with a new approved version. The scope expanded from simple operational warnings to sophisticated avionics modifications and flight manual overhauls."},"complexity_factors":["Multiple amendment layers (Amendment 3) that supersede previous requirements (Requirements 6-11 all marked 'Superseded by Requirement 13')","Cross-references to Brazilian aviation authority directives (DAC AD 2001-05-02R2) and US FAA directives (AD 2001-20-17)","Specific technical document references requiring precise revision tracking (SB 120-30-0033 Rev 01, 02, or 03; AFM-120/813 Revision 70)","Staggered compliance deadlines with different applicability (some 'not applicable', some calendar-based, some flight hours-based)","Technical aviation terminology requiring domain knowledge (TIS = Time In Service, KIAS = Knots Indicated Air Speed, AFM = Aircraft Flight Manual, deice boots)","Conditional installation sequence (Requirement 5 'should be installed after or together with' Requirement 3)"],"plain_english_summary":"This CASA Airworthiness Directive mandates fixes for Embraer EMB-120 (Brasilia) aircraft in Australia to prevent loss of control in icing conditions. It requires installation and modification of a cockpit low‑speed warning (audio/visual, with silencing when gear is down), adoption of a specified AFM revision, and removal of the de‑icing “light‑heavy” switch.\n\nIt matters because airframe icing can mask dangerous speed decay and has already caused loss‑of‑control events, so these measures improve pilot warning and procedures."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions","history":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions/history","analysis":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions/analysis","conflicts":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions/conflicts","importantCases":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions/important-cases","documents":"/api/acts/ad-emb-120-27-amdt-3-icing-conditions/documents"}}