{"id":"F2006B09231","name":"AD/DHC-8/73 Amdt 1 - Airstair Door","slug":"ad-dhc-8-73-amdt-1-airstair-door","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53115,"registerId":"commonwealth-F2006B09231-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-8/73 Amdt 1 - Airstair Door","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)  \n![](image.002.png)  \nBombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/DHC-8/73 and issues the following 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\nAD/DHC-8/73\n\nAmdt 1\n\n  \nAirstair Door 4/2001\n\nApplicability: Model DHC-8 series 100, 200, and 300 aircraft, serial numbers 003 through 550.\n\nRequirement: Modify the airstair door in accordance with the requirements of Transport Canada AD CF-2000-19R1.\n\nCompliance: Before 19 October 2001, unless already accomplished. This amendment becomes effective on 19 April 2001.\n\nBackground: Transport Canada received a significant number of reports which detail various problems of the airstair door failing to open following flight. Several modifications have been developed to address these problems and their incorporation will improve the reliability of the airstair door, and ensure that problems with the door do not impede aircraft egress during emergency conditions.\n\nAmendment 1 is issued in response to a new Transport Canada AD which addresses a change in affected aircraft serial numbers, indicates approval of later revisions of two service bulletins, and adds an alternate method of addressing the bending of the gas springs. As well, the compliance schedule has been extended.\n\nThe original issue of this Airworthiness Directive became effective on 2 November 2000.\n\n![](image.003.png)  \n\nDavid Alan Villiers.\n\nDelegate of the Civil Aviation Safety Authority 5 March 2001\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 21 March 2001.","sortOrder":0}],"analysis":{"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"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 1 changed the AD's scope by updating the affected serial number range, approving later revisions of two service bulletins, adding an alternate method to address bending of gas springs, and extending the compliance schedule (Background)."},"complexity_factors":["Applicability limited by serial number range (003–550) — requires operators to check fleet eligibility (Applicability).","Mandates compliance with an external instrument: Transport Canada AD CF-2000-19R1, requiring cross-reference to non‑Australian documents (Requirement).","Includes technical fixes and an alternate method for bent gas springs, which may require engineering assessment or parts changes (Background / Requirement).","Amendment approves later revisions of two service bulletins — operators must confirm the correct bulletin revision and revision history (Background).","Compliance timing: fixed deadline (before 19 October 2001) and effective date (19 April 2001) creates scheduling pressure and potential aircraft downtime (Compliance).","Revocation and replacement of a prior AD means affected operators must reconcile prior compliance records with the amended requirements (preamble).","Enforcement delegated under CAR 1998 subregulation 39.1(1) — discretionary administrative enforcement and recordkeeping obligations rest with CASA/its delegate (preamble).","Relatively narrow technical scope limits policy complexity but raises operational complexity for maintenance planning and parts procurement."],"plain_english_summary":"Requires modification of the airstair door on Bombardier DHC‑8 Series 100/200/300 aircraft (serial numbers 003–550) to meet Transport Canada AD CF‑2000‑19R1. Operators must complete the work by 19 October 2001 (AD effective 19 April 2001).\n\nThe AD responds to reports of airstair doors failing to open after flight. Amendment 1 changes the affected serial range, approves later service bulletin revisions, adds an alternate repair for bent gas springs, and extends the compliance schedule."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope — safety modifications to DHC-8 airstair doors. The changes are technical adjustments (serial number range, approved repair methods, deadline extension) rather than expansion into new aircraft systems or operational areas."},"complexity_factors":["Very short document (under 400 words)","Only 3 defined elements: applicability (aircraft models/serials), requirement (single reference to Canadian AD), and compliance date","No nested conditional logic — single requirement with single deadline","No internal cross-references to other legislation sections","Incorporates external technical document by reference (Transport Canada AD CF-2000-19R1) rather than reproducing instructions","Straightforward amendment structure: replaces previous AD entirely, explains changes in plain language background section"],"plain_english_summary":"The Civil Aviation Safety Authority requires operators of Bombardier DHC‑8 Dash 8 series 100/200/300 (serials 003–550) to modify the built‑in airstair door per Transport Canada AD CF‑2000‑19R1 to prevent the door jamming shut and blocking emergency evacuation.  \n\nThis updated safety order revises the affected serial range, approves newer repair instructions, allows an alternative for bent gas springs, and extends the compliance deadline to 19 October 2001."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door","history":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door/history","analysis":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door/analysis","conflicts":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door/conflicts","importantCases":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door/important-cases","documents":"/api/acts/ad-dhc-8-73-amdt-1-airstair-door/documents"}}