Proposed rule · 2026-18956

Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

The FAA proposes to adopt a new airworthiness directive (AD) for certain De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Model DHC-8-401 and DHC-8-402 airplanes. This proposed AD was prompted by a report that instructions for fay, fillet, and rivet dome sealing were omitted for a bracket installed on the inboard surface of the tank rib, which could allow fuel to leak from the wing fuel tank into the wing dry bay. This proposed AD would require a detailed visual inspection of the affected bracket assembly for signs of fuel leakage and for the presence of fillet seal and fastener dome seal, and applicable on-condition actions. The FAA is proposing this AD to address the unsafe condition on these products.