{"id":"F2006B09503","name":"AD/EMB-120/14 - Fuselage Aft Section Drain","slug":"ad-emb-120-14-fuselage-aft-section-drain","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54052,"registerId":"commonwealth-F2006B09503-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EMB-120/14 - Fuselage Aft Section Drain","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nEmbraer EMB-120 (Brasilia) Series Aeroplanes\n\nAD/EMB-120/14 Fuselage Aft Section Drain 2/96\n\nApplicability: Model EMB-120 aircraft with serial numbers 120003, 120004, 120006 through 120018, 120020 through 120028, 120030 through 120032, 120034 through 120076,\n\n120078 through 120121, 120123 through 120217, and 120219 through 120305.\n\nRequirement: Install an additional drain fitting at Station 1619.0 in accordance with Embraer Service Bulletin 120-53-0064.\n\nNote: Brazil CTA AD 95-11-01 Amdt 39-750 refers.\n\nCompliance: Within 400 hours time in service after 1 February 1996.\n\nBackground: A report was received of a case of jamming of the elevator control cables during flight. This occurrence was found to be due to the freezing of water that had accumulated inside the fuselage, between the rear pressure bulkhead and the APU firewall.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect. It has not expanded beyond its original purpose of preventing elevator control cable jamming through improved drainage."},"complexity_factors":["Single, specific technical requirement (install one drain fitting)","Clear applicability list (specific serial numbers)","Single compliance deadline (400 hours after fixed date)","No defined terms section","No cross-references to other legislation (only references Embraer technical document and related Brazilian directive)","Minimal conditional logic (straightforward applicability test)","Short document (approximately 150 words)"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for specific Embraer EMB-120 \"Brasilia\" aircraft.\n\n**What it does:**\n- Requires owners/operators of certain EMB-120 planes to install an extra drain hole at a specific location in the rear fuselage (Station 1619.0)\n- The work must follow Embraer's official Service Bulletin 120-53-0064\n\n**Who it affects:**\n- Owners and operators of EMB-120 aircraft with specific serial numbers (roughly serial numbers 120003 through 120305, with some gaps)\n\n**Why it matters:**\n- Water was collecting in the rear fuselage area and freezing, which caused elevator control cables to jam during flight\n- Jammed elevator controls mean pilots can't control the plane's pitch (nose up/down), creating a serious safety risk\n- This directive prevents ice formation by improving drainage, ensuring flight controls work properly in cold conditions\n\n**Deadline:**\n- Must be completed within 400 flight hours after 1 February 1996"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text is a narrowly targeted safety directive prescribing one mechanical modification for a defined set of serial-numbered aircraft to address a specific failure mode (freezing-related elevator cable jamming). The AD itself contains no language indicating an expansion or narrowing of scope from its expressed purpose; it prescribes the corrective action, the exact method to be used, the affected serial numbers, and a compliance deadline. (Applicability; Requirement; Compliance; Background)"},"complexity_factors":["Narrow, serial-numbered applicability requiring operators to check aircraft identity (Applicability)","Single, prescriptive technical action (install one drain fitting) specified by a manufacturer's service bulletin (Requirement)","Fixed compliance window (400 hours time-in-service after 1 Feb 1996) creating scheduling pressure (Compliance)","Need to obtain and follow an external document (Embraer Service Bulletin 120-53-0064) for the exact method (Requirement)","Operational costs and downtime for maintenance (implicit from Requirement and Compliance)","No alternative compliance procedures or exemptions included in the AD text (Requirement)"],"plain_english_summary":"This AD mandates installing an additional drain fitting at station 1619.0 on specified Embraer EMB-120 serial-numbered aeroplanes to prevent water pooling that can freeze and jam elevator control cables. Affected owners/operators must have the drain fitted per Embraer Service Bulletin 120-53-0064 within 400 hours TIS after 1 Feb 1996. The safety gain targets a small, identified subset of the fleet; compliance costs (parts, labour, downtime) fall to those operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain","history":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain/history","analysis":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain/analysis","conflicts":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain/conflicts","importantCases":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain/important-cases","documents":"/api/acts/ad-emb-120-14-fuselage-aft-section-drain/documents"}}