EASA AD CF-2026-47 — Wing – Wing Access Panels with Un-trimmed Stiffeners and/or Reduced Thickness

Summary

Canadian Airworthiness Directive CF-2026-47 addresses wing access panels with un-trimmed stiffeners and/or reduced thickness on De Havilland Aircraft of Canada Limited model DHC-8 series 100, 200, and 300 aircraft. The directive focuses on ensuring the right-hand wing access panel stiffener is trimmed and that both left-hand and right-hand access panels of correct thickness are installed to prevent potential fuel tank ignition risks. This AD applies to all serial numbers of the specified models and supersedes a previous directive issued in 2025.

What Changed

CF-2026-47 supersedes AD CF-2025-33 and introduces updated inspection and modification requirements based on a revised Service Bulletin 8-57-50 Rev. A. It clarifies previous trimming instructions that were misleading and prohibits installation of certain thinner wing access panel part numbers on DHC-8-300 series aircraft. The directive also mandates reidentification of parts to maintain configuration control.

Why It Matters

This directive is critical for aviation professionals to mitigate the risk of fuel tank ignition caused by contact between wing access panel stiffeners and incorrectly oriented fuel line couplings during lightning strikes. Operators and maintenance organizations must ensure compliance to maintain airworthiness and safety. Proper inspection, modification, and parts control prevent potential hazards and regulatory non-compliance.

What To Do

Operators of affected DHC-8 models must inspect and, if necessary, modify the left-hand and right-hand outer wing access panels within 8000 flight hours or 48 months from 16 July 2025, whichever occurs first. Installation of prohibited thinner access panels on DHC-8-300 series aircraft is forbidden from the effective date of this AD. For aircraft previously modified under the initial Service Bulletin, a verification inspection and possible rework are required within the same compliance timeframe.