{"id":"F2008L00776","name":"AD/ERJ-170/13 - Ram Air Turbine Bearings","slug":"ad-erj-170-13-ram-air-turbine-bearings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72843,"registerId":"commonwealth-F2008L00776-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Embraer ERJ-170 Series Aeroplanes","sectionType":"division","heading":"Embraer ERJ-170 Series Aeroplanes","content":"### Embraer ERJ-170 Series Aeroplanes\n\n| AD/ERJ-170/13 | Ram Air Turbine Bearings | 4/2008 |\n| ------------- | ------------------------ | ------ |\n\n| Applicability: | Embraer ERJ-170 aircraft models equipped with Ram Air Turbine (RAT) part number (P/N) 1703781 and serial numbers (S/N) 0005 and 0101 through 0419 inclusive.                                                                                                                                                                                                                                                                                                                                                                                                                         |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | 1. Verify the installed S/N of the RAT.2. If the RAT has S/N 0110, 0150, 0255 or 0354 through 0419, reidentify the RAT P/N from 1703781 to 1703781A.3. If RAT has S/N 0005, 0101 through 0109, 0111 thru 0149, 0151 through 0254 or 0256 through 0353, replace the RAT with a RAT bearing P/N 1703781A.The detailed instructions and procedures to accomplish this AD are described in Embraer Service Bulletin No. 170-24-0041 original issue, or later revisions approved by the ANAC.Note: AGÊNCIA NACIONAL DE AVIAÇÃO CIVIL - BRAZIL AD 2007-12-01 dated 24 January 2008 refers. |\n| Compliance:    | 1. Within the next 1300 flight hours or 6 months after the effective date of this AD, whichever occurs first.2. At the time of verification as detailed in Requirement 1 of this AD.3. Within the next 6000 flight hours or 26 months after the effective date of this AD, whichever occurs first.                                                                                                                                                                                                                                                                                   |\n|                | This Airworthiness Directive becomes effective on 10 April 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |\n| Background:    | It has been found the occurrence of a failed bearing within the RAT generator may lead to a RAT generator failure. The RAT generator was designed to provide emergency electrical power to essential systems in case of loss of all other sources of aircraft AC electrical power.                                                                                                                                                                                                                                                                                                   |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n21 February 2008","sortOrder":0},{"sectionNumber":"AD/ERJ-170/13","sectionType":"part","heading":"AD/ERJ-170/13","content":"## AD/ERJ-170/13","sortOrder":1},{"sectionNumber":"Ram Air Turbine Bearings","sectionType":"part","heading":"Ram Air Turbine Bearings","content":"## Ram Air Turbine Bearings","sortOrder":2},{"sectionNumber":"4/2008","sectionType":"part","heading":"4/2008","content":"## 4/2008","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard, targeted Airworthiness Directive addressing a specific safety defect in a specific aircraft component. The scope remains precisely limited to the identified bearing failure risk in the specified RAT units."},"complexity_factors":["Multiple serial number ranges with different treatment requirements (relabel vs replace)","Three separate compliance deadlines with 'whichever occurs first' conditions","Cross-reference to Brazilian aviation authority (ANAC) and Embraer Service Bulletin for technical procedures","Nested conditional logic: applicability depends on part number AND serial number, then requirements depend on specific serial number sub-ranges"],"plain_english_summary":"This AD requires owners/operators of certain Embraer ERJ‑170s to inspect and remediate Ram Air Turbine (RAT) units with part number 1703781 because faulty bearings can cause emergency‑power failure. It targets specific serial numbers and mandates serial‑number checks within 1,300 flight hours or 6 months, relabeling of some units, and replacement of the rest with part 1703781A within 6,000 flight hours or 26 months.\n\nIt matters because RAT failure could remove last‑resort electrical power in an emergency."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Scope remains narrowly targeted to Embraer ERJ-170 aeroplanes equipped with RAT P/N 1703781 and the serial numbers listed. The instrument implements verification, reidentification or replacement for those specific units and does not expand applicability beyond the serial-number set or introduce additional affected parts."},"complexity_factors":["Narrow, technical applicability limited to RAT P/N 1703781 with multiple specific serial-number ranges (adds administrative complexity in fleet tracking) (Applicability).","Two distinct remedies: reidentification of the P/N for some S/Ns and physical bearing replacement for others (Requirement 2–3).","Multiple compliance windows with different deadlines (verification: 1,300 fh/6 months; replacement: 6,000 fh/26 months) requiring scheduling within operational constraints (Compliance).","Dependence on an external document for procedures (Embraer Service Bulletin 170-24-0041) and acceptance of later revisions by the regulator increases procedural reliance and limited regulatory discretion (Requirement/Note).","Recordkeeping and part-number control burden for operators to demonstrate compliance and to ensure correct parts are installed and identified (Requirement/Compliance).","Linkage to a foreign authority AD (ANAC Brazil) may require cross-jurisdictional coordination for operators or maintainers (Note/Background)."],"plain_english_summary":"This AD requires operators of Embraer ERJ-170 aircraft fitted with Ram Air Turbine (RAT) P/N 1703781 to check the RAT serial number and either reidentify the part as P/N 1703781A or replace the RAT bearing with P/N 1703781A, following Embraer Service Bulletin 170-24-0041. Verification is due within 1,300 flight hours or 6 months; replacement within 6,000 flight hours or 26 months. Operators pay for inspections/replacements and the regulator enforces compliance to reduce the risk of RAT generator failure."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings","history":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings/history","analysis":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings/analysis","conflicts":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings/conflicts","importantCases":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings/important-cases","documents":"/api/acts/ad-erj-170-13-ram-air-turbine-bearings/documents"}}