{"id":"F2006L00442","name":"AD/DHC-8/108 - Horizontal Stabiliser Attachment Fittings","slug":"ad-dhc-8-108-horizontal-stabiliser-attachment-fittings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":117129,"registerId":"commonwealth-F2006L00442-current","compilationNumber":null,"startDate":"2026-04-03","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-8/108 | Horizontal Stabiliser Attachment Fittings | 3/2006 |\n| ------------ | ----------------------------------------- | ------ |\n\n| Applicability: | Model DHC-8-400, DHC-8-401, and DHC-8-402 aircraft, serial numbers 4001, and 4003 through 4081.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the requirements of Transport Canada AD CF-2005-07.Note: Bombardier Service Bulletin 84-55-02 Revision A, or later Transport Canada approved revision, refers.                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of16 March 2006.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n|                | This Airworthiness Directive becomes effective on 16 March 2006.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n| Background:    | The manufacturer received reports of delamination and extrusion of laminated shims from the interface of the horizontal stabiliser attachment fittings. In addition, during removal of the horizontal stabiliser for replacement of the laminated shims with solid shims, it was discovered that the torque values of some bolts at the attachment locations on some aircraft were inconsistent with maintenance manual requirements. This condition, unless corrected, could lead to a reduction in the fatigue life of the bolts, and consequent reduction of structural integrity of the horizontal stabiliser attachment. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n3 February 2006","sortOrder":0},{"sectionNumber":"AD/DHC-8/108","sectionType":"part","heading":"AD/DHC-8/108","content":"## AD/DHC-8/108","sortOrder":1},{"sectionNumber":"Horizontal Stabiliser Attachment Fitting","sectionType":"part","heading":"Horizontal Stabiliser Attachment Fittings","content":"## Horizontal Stabiliser Attachment Fittings","sortOrder":2},{"sectionNumber":"3/2006","sectionType":"part","heading":"3/2006","content":"## 3/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This AD implements the measures set out in Transport Canada AD CF‑2005‑07 for the specified DHC‑8‑400 serial numbers to address shim delamination and incorrect bolt torques. It does not expand applicability or introduce additional mandatory measures beyond the referenced AD and service bulletin, so scope remains aligned with the original corrective intent."},"complexity_factors":["Narrow, serial-numbered applicability (only DHC‑8‑400 series serials 4001, 4003–4081) reduces scope but requires fleet-specific tracking.","Direct cross-reference to external instruments (Transport Canada AD CF‑2005‑07 and Bombardier Service Bulletin 84‑55‑02 Rev A or later approved revision) creates dependence on outside documents and revision-tracking.","Technical tasks (detecting shim delamination, replacing laminated shims with solid shims, verifying bolt torque) require specialised maintenance resources and downtime.","Compliance timing is fixed (effective date 16 March 2006), imposing scheduling and potential operational disruption.","Enforcement delegated to CASA (delegate signature) — little discretion in the AD text, but practical discretion exists in approving later Transport Canada revisions."],"plain_english_summary":"Requires operators of specified Bombardier DHC‑8‑400 series aeroplanes (serials 4001, 4003–4081) to perform inspections and corrective work on horizontal stabiliser attachment fittings in accordance with Transport Canada AD CF‑2005‑07 and Bombardier Service Bulletin 84‑55‑02 Rev A (or later approved revision). Effective 16 March 2006.\n\nThe AD cites reports of shim delamination and incorrect bolt torques that could reduce bolt fatigue life and structural integrity. Aircraft owners/operators bear inspection and repair costs; the regulator (CASA delegate) enforces compliance and approves acceptable revisions."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 3 defined applicability criteria (specific aircraft models and serial numbers)","Single requirement referencing external documents rather than spelling out technical steps","No nested exceptions or conditional logic","No cross-references to other legislation beyond the referenced Transport Canada AD and manufacturer service bulletin","Straightforward compliance date with no phased or conditional timelines"],"plain_english_summary":"This AD mandates inspection and repair of horizontal stabiliser attachment fittings on certain Bombardier DHC-8-400 (Q400) aeroplanes (S/N 4001, 4003–4081) after delamination/extrusion of laminated shims and evidence of incorrect bolt torque. It affects owners/operators of those early Q400s because unresolved damage can reduce bolt fatigue life and risk tail-attachment failure.\n\nCompliance follows Transport Canada AD CF-2005-07 and Bombardier Service Bulletin 84-55-02 Rev A, due by 16 March 2006."},"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-8-108-horizontal-stabiliser-attachment-fittings","history":"/api/acts/ad-dhc-8-108-horizontal-stabiliser-attachment-fittings/history","analysis":"/api/acts/ad-dhc-8-108-horizontal-stabiliser-attachment-fittings/analysis","conflicts":"/api/acts/ad-dhc-8-108-horizontal-stabiliser-attachment-fittings/conflicts","importantCases":"/api/acts/ad-dhc-8-108-horizontal-stabiliser-attachment-fittings/important-cases","documents":"/api/acts/ad-dhc-8-108-horizontal-stabiliser-attachment-fittings/documents"}}