{"id":"F2006B09472","name":"AD/EMB-110/30 Amdt 1 - Flap Control and Protection Unit - Modification","slug":"ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53967,"registerId":"commonwealth-F2006B09472-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-110/30 Amdt 1 - Flap Control and Protection Unit - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Embraer EMB-110 (Bandeirante) Series Aeroplanes\n\n \n\nAD/EMB-110/30\n\nAmdt 1\n\n\nFlap Control and Protection Unit - Modification 4/85\n\n \n\nApplicability: All models equipped with multiposition flap control switch. Document: Embraer SB 110-27-073 R1.\n\nNote: Brazilian AD 84-01-01 refers.\n\n \n\nCompliance: Part I: Within 100 hours time in service after 31 March 1984. Part II: Within 250 hours time in service after 30 April 1985.\n\nBackground: a. Inadvertent flap extension due to short circuit in flap system control and protection unit have been reported.\n\n \n\nb. Amendment 1 includes a further modification to prevent tripping the Flap control circuit breaker when the fire extinguishing system is actuated.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment expands the original directive’s technical scope. The original AD addressed inadvertent flap extension due to a short circuit in the flap control and protection unit (Background a). Amendment 1 adds a further modification specifically intended to prevent tripping of the flap control circuit breaker when the fire extinguishing system is actuated (Background b). Thus the instrument’s required modifications were broadened to cover that additional failure mode."},"complexity_factors":["Narrow technical scope limited to EMB-110 aircraft with multiposition flap control switch (Applicability)","Two separate hour-based compliance deadlines (Part I: 100 hrs after 31 March 1984; Part II: 250 hrs after 30 April 1985) (Compliance)","Dependence on an external technical document (Embraer SB 110-27-073 R1) for detailed modification steps (Document)","Amendment introduces an additional, related modification (to prevent circuit-breaker tripping when the fire extinguishing system is actuated) layered onto the original requirement (Background b)","Cross-reference to a foreign authority’s AD (Brazilian AD 84-01-01), implying coordination but no additional procedural complexity in this text (Note)"],"plain_english_summary":"What this instrument does mechanically\n\n- This Airworthiness Directive (AD) mandates a hardware modification to the flap control and protection unit on Embraer EMB-110 (Bandeirante) aeroplanes that have a multiposition flap control switch. The modification is carried out according to Embraer Service Bulletin 110-27-073 R1 (Document) and is referenced to a related Brazilian AD (Note). (Applicability; Document; Note)\n\nWho must act and within what timeframes\n\n- Aircraft operators (owners/lessees/maintenance organisations responsible for maintenance) must install the modification. The AD is split into two compliance parts with distinct deadlines measured in hours time-in-service: Part I must be done within 100 hours TIS after 31 March 1984; Part II must be done within 250 hours TIS after 30 April 1985. (Compliance)\n\nWhy the change was issued (official rationale and the additional amendment)\n\n- The AD was issued after reports of inadvertent flap extension caused by a short circuit in the flap system control and protection unit. (Background a)\n- Amendment 1 to the AD adds a further modification intended to stop the flap control circuit breaker from tripping when the fire extinguishing system is actuated. That further modification is part of this amendment’s scope. (Background b)\n\nWho pays, who decides, and what behaviour changes\n\n- Who pays: aircraft operators/fleet owners bear the direct costs (parts, labour, downtime) required to carry out the modification per the service bulletin. (Applicability; Compliance; Document)\n- Who decides: the Civil Aviation Safety Authority issued the AD; the detailed technical steps are provided by Embraer’s service bulletin that the AD mandates. (Document)\n- Behaviour changes required: operators must schedule maintenance to perform the mandated modification within the stated flight-hour windows, follow the Embraer service bulletin instructions, and update maintenance records to show compliance. (Compliance; Document)\n\nCompliance burden, incentives and likely market effects\n\n- Compliance burden: a one-time technical action involving parts and labour, and operator scheduling to meet the hour-based deadlines. (Compliance)\n- Incentives: operators must comply to keep aircraft airworthy; maintenance providers (MROs) receive demand for performance of the modification. (Applicability; Document)\n- Opportunity costs and operational impact: aircraft may need to be scheduled out of service within the compliance windows, creating short-term downtime costs and possible rearrangement of operations. (Compliance)\n\nImplementation risk and dependences\n\n- Effectiveness depends on completing the exact modification specified in Embraer SB 110-27-073 R1. If the service bulletin is not correctly followed, the reported failure modes (inadvertent flap extension; circuit breaker tripping during fire-extinguishing actuation) may persist. (Document; Background a, b)\n- The AD references a Brazilian AD (Note), indicating cross-jurisdictional coordination; compliance depends on the technical instructions supplied by the manufacturer and the regulatory direction of the Australian authority. (Note; Document)\n\nTrade-offs and concentrated vs diffuse impacts\n\n- The safety benefit (reduction of the specific electrical failure modes) accrues to each modified aircraft and its occupants and is concentrated on operators that implement the modification promptly. The cost of compliance is borne by those same operators. Maintenance industry participants gain concentrated demand for parts and labour during compliance activity. (Background a, b; Compliance; Document)\n\nSource citations\n\n- Applicability; Document; Note; Compliance; Background a; Background b."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard aircraft-specific airworthiness directive with a narrow, technical scope focused on a single safety modification. The amendment (Amdt 1) adds one specific technical improvement (fire extinguisher system interaction) without expanding beyond the original safety purpose of preventing inadvertent flap extension."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 defined compliance deadlines (Part I and Part II)","Single technical reference to external document (Embraer SB 110-27-073 R1)","No nested exceptions or conditional logic","Straightforward applicability criteria (all models with multiposition flap control switch)","Minimal cross-referencing (one note to Brazilian AD 84-01-01)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nThis directive requires owners and operators of **Embraer EMB-110 Bandeirante aircraft** (a Brazilian-made twin-turboprop plane) to modify the **flap control and protection unit** — the system that controls the wing flaps (the movable surfaces on the back of wings that help with takeoff and landing).\n\n**Why it matters:**\nThere were reports of **flaps extending accidentally** due to electrical short circuits in the control unit. This is dangerous because unexpected flap deployment during flight can cause loss of control or structural damage. The amendment adds an extra fix to prevent the flap circuit breaker from tripping (cutting out) when the fire extinguishing system is used — ensuring pilots retain flap control during an emergency.\n\n**Who must comply:**\n- All EMB-110 models with a **multiposition flap control switch**\n- **Part I:** Modification required within 100 flight hours after 31 March 1984\n- **Part II:** Additional modification required within 250 flight hours after 30 April 1985\n\n**How to comply:**\nFollow the technical instructions in **Embraer Service Bulletin 110-27-073 Revision 1** (the manufacturer's official repair notice)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification","history":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification/history","analysis":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification/analysis","conflicts":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification/conflicts","importantCases":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification/important-cases","documents":"/api/acts/ad-emb-110-30-amdt-1-flap-control-and-protection-unit-modification/documents"}}