{"id":"F2006B07343","name":"AD/TB20/38 - Seat Unlocking","slug":"ad-tb20-38-seat-unlocking","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49420,"registerId":"commonwealth-F2006B07343-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 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\nAerospatiale (Socata) TB 20 (Trinidad) Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/TB 20/38 Seat Unlocking 7/2001","sectionType":"part","heading":"AD/TB 20/38 Seat Unlocking 7/2001","content":"# AD/TB 20/38 Seat Unlocking 7/2001\n\nApplicability: All TB 20 aircraft without Socata modification No. 165 incorporated in production. Requirement: Action in accordance with Socata Service Bulletin No. 10-115-25.\n\nNote: DGAC AD 2001-005(A) refers.\n\nCompliance: Unless already accomplished, at the next scheduled inspection after 19 July 2001.\n\nThis Airworthiness Directive becomes effective on 12 July 2001.\n\nBackground: The manufacturer received reports of front seats unlocking. Investigation revealed interference of the seat pan with the locking mechanism as the cause. This Directive requires modification action.\n\n![Signature of David Alan Villiers Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 1 June 2001\n\n![](image.001.png)","sortOrder":1}],"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific mechanical defect in a specific aircraft model. There is no evidence of scope creep; it targets exactly the safety issue described in the background."},"complexity_factors":["Very short document (under 300 words)","Only 2 defined technical references (Modification No. 165 and Service Bulletin No. 10-115-25)","Single straightforward requirement with one condition (unless already accomplished)","No nested exceptions or conditional logic","Clear applicability test (all TB 20s without specific modification)","Single compliance deadline tied to existing maintenance schedule"],"plain_english_summary":"This CASA Airworthiness Directive orders owners/operators of Aerospatiale (Socata) TB 20 \"Trinidad\" aeroplanes that were not fitted with Modification No. 165 at manufacture to repair a front-seat locking defect that can allow seats to unlock in flight.  \n\nThe mandated fix follows Socata Service Bulletin No. 10-115-25 and must be carried out by the next scheduled inspection after 19 July 2001. It addresses a serious safety risk from sudden seat movement in flight."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD confines action to TB 20 aeroplanes lacking Socata modification No. 165 and requires the specific manufacturer service bulletin modification to correct the reported seat‑unlocking defect. It does not expand applicability beyond that aircraft subset or add continuing obligations; scope is limited to correcting the identified unsafe condition (Applicability; Requirement; Background)."},"complexity_factors":["Narrow applicability: applies only to TB 20 aircraft without Socata modification No. 165 (Applicability).","External reference: mandates compliance with Socata Service Bulletin No. 10-115-25 rather than prescribing detailed steps in the AD (Requirement).","Fixed compliance window tied to maintenance scheduling: next scheduled inspection after 19 July 2001 (Compliance).","Single, discrete unsafe condition identified (seat pan interference causing front-seat unlocking) limiting technical scope (Background).","Regulatory provenance and enforcement via CASA delegate; minimal discretionary implementation detail provided (opening paragraph; signature).","Cross-reference to DGAC AD 2001-005(A) creates an additional external reference point for implementers (Note)."],"plain_english_summary":"This Airworthiness Directive orders owners/operators of Socata (Aerospatiale) TB 20 (Trinidad) aeroplanes built without Socata modification No. 165 to carry out the modification described in Socata Service Bulletin No. 10-115-25 to stop front seats unlocking due to seat‑pan interference (Applicability; Requirement; Background). The CASA delegate issued the AD; compliance is required at the next scheduled inspection after 19 July 2001, and the cost and work fall to aircraft owners/operators (Compliance)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tb20-38-seat-unlocking","history":"/api/acts/ad-tb20-38-seat-unlocking/history","analysis":"/api/acts/ad-tb20-38-seat-unlocking/analysis","conflicts":"/api/acts/ad-tb20-38-seat-unlocking/conflicts","importantCases":"/api/acts/ad-tb20-38-seat-unlocking/important-cases","documents":"/api/acts/ad-tb20-38-seat-unlocking/documents"}}