{"id":"F2009L03828","name":"AD/DHC-8/152 - Series 400 Door Stops","slug":"ad-dhc-8-152-series-400-door-stops","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":81066,"registerId":"commonwealth-F2009L03828-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bombardier (Boeing Canada/De Havilland) ","sectionType":"division","heading":"Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes","content":"### Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes\n\n| AD/DHC-8/152 | Series 400 Door Stops | 12/2009 |\n| ------------ | --------------------- | ------- |\n\n| Applicability: | Bombardier Inc. Models DHC-8-400, DHC-8-401 and DHC-8-402 with Serial Numbers 4002 and subsequent.                                                                                      |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Revise the Transport Canada-approved maintenance schedule and the DHC-8-Q400 Maintenance Requirements Manual in accordance with Transport Canada ADCF-2001-23.                          |\n| Compliance:    | Within 30 days after the effective date of this Directive.                                                                                                                              |\n|                | This Airworthiness Directive becomes effective on 19 November 2009.                                                                                                                     |\n| Background:    | During structural fatigue tests, failures of the door stops were discovered at the aft passenger entry door and the aft baggage door. The door stops are principal structural elements. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n27 September 2009","sortOrder":0},{"sectionNumber":"AD/DHC-8/152","sectionType":"part","heading":"AD/DHC-8/152","content":"## AD/DHC-8/152","sortOrder":1},{"sectionNumber":"Series 400 Door Stops","sectionType":"part","heading":"Series 400 Door Stops","content":"## Series 400 Door Stops","sortOrder":2},{"sectionNumber":"12/2009","sectionType":"part","heading":"12/2009","content":"## 12/2009","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific structural fatigue issue with door stops on specific aircraft models. There is no evidence of scope creep; it remains a targeted safety directive without expansion into unrelated operational areas."},"complexity_factors":["Single, specific technical requirement (revising maintenance schedules)","Clear applicability criteria (three specific models, serial number cutoff)","Simple compliance timeline (30 days from effective date)","No defined terms section or complex cross-referencing","Straightforward background explanation without nested conditions","Short document length (approximately 150 words of substantive content)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Bombardier DHC-8-400 series (Q400) aircraft, serials 4002 and up, to update maintenance manuals and schedules within 30 days to address the rear passenger and rear baggage door stops.  \n\nFatigue testing showed these door stops—classified as principal structural elements—could fail, so the AD is a preventative safety action to ensure proper inspection and upkeep to protect structural integrity in flight."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive does not expand or narrow the aircraft types or introduce new kinds of action beyond updating maintenance documentation per Transport Canada ADCF-2001-23. It prescribes procedural revisions for the listed serial-numbered models and sets a 30-day compliance deadline (Applicability; Requirement; Compliance)."},"complexity_factors":["Narrow technical scope: applies only to Bombardier DHC-8-400, -401 and -402 with serial numbers 4002 and subsequent (Applicability).","Procedure-driven compliance: requires revision of approved maintenance schedule and the DHC-8-Q400 Maintenance Requirements Manual, rather than physical modification (Requirement).","Reference to external document increases dependency: compliance must follow Transport Canada ADCF-2001-23, requiring operators to obtain and interpret that document (Requirement).","Short compliance window: 30 days from the Directive’s effective date imposes operational and administrative scheduling pressure (Compliance).","Safety-critical basis: door stops are described as principal structural elements, which raises inspection/maintenance priority and potential operational disruption if non-compliance is found (Background)."],"plain_english_summary":"This Airworthiness Directive requires operators of Bombardier DHC-8 Series 400 aeroplanes (serial numbers 4002 and later) to update their Transport Canada–approved maintenance schedule and the DHC-8‑Q400 Maintenance Requirements Manual to reflect Transport Canada ADCF‑2001‑23. The change must be implemented within 30 days. The directive responds to structural fatigue tests that found failures of door stops on the aft passenger and aft baggage doors, which are identified as principal structural elements."},"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-dhc-8-152-series-400-door-stops","history":"/api/acts/ad-dhc-8-152-series-400-door-stops/history","analysis":"/api/acts/ad-dhc-8-152-series-400-door-stops/analysis","conflicts":"/api/acts/ad-dhc-8-152-series-400-door-stops/conflicts","importantCases":"/api/acts/ad-dhc-8-152-series-400-door-stops/important-cases","documents":"/api/acts/ad-dhc-8-152-series-400-door-stops/documents"}}