AD 2026-11-06 Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

Models named: DHC-8-101, -102, -103, -106, DHC-8-201, -202, DHC-8-301, -311, -315, DHC-8-400. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to all De Havilland Aircraft of Canada Limited (Type Certificate previously held by Bombardier, Inc.) airplanes, certificated in any category, identified in paragraphs (c)(1) through (4) of this AD. (1) Model DHC-8-101, -102, -103, and -106 airplanes. (2) Model DHC-8-201 and -202 airplanes. (3) Model DHC-8-301, -311, and -315 airplanes. (4) Model DHC-8-400, -401, and -402 airplanes.

Comply with this AD within the compliance times specified, unless already done.

For Model DHC-8-101, -102, -103, and -106 airplanes, Model DHC-8-201 and -202 airplanes, and Model DHC-8-301, -311, and -315 airplanes: Do the actions specified in paragraphs (g)(1) through (4) of this AD. (1) As of 60 days after the effective date of this AD: At the next flight compartment windshield replacement, do a detailed inspection for cracks and corrosion of the barrel nuts at the windshield side posts and, before further flight, do all applicable corrective actions, in accordance with the Accomplishment Instructions of De Havilland Aircraft of Canada Limited Service Bulletin 8-05-11, dated April 29, 2022. Repeat the inspection thereafter at each flight compartment windshield replacement. (2) Within 6 years since entry into service, or within 60 days after the effective date of this AD, whichever occurs later, do detailed inspections for cracks and corrosion of the barrel nuts at the nose landing gear trunnion plate assemblies, nacelle lower longeron attachments, the front, mid and rear spar horizontal stabilizer to vertical stabilizer attachments, the bathtub fittings attachments, the wing rib YW23.858 assemblies, and the wing rib YW42.00 assemblies, and before further flight, do all applicable corrective actions, in accordance with the Accomplishment Instructions of De Havilland Aircraft of Canada Limited Service Bulletin 8-05-11, dated April 29, 2022. Repeat the inspection thereafter at intervals not to exceed 6 years. (3) Within 6 years since entry into service, or within 60 days after the effective date of this AD, whichever occurs later, do a detailed inspection for cracks and corrosion of the barrel nuts, having part number (P/N) DSC228-5, at the control attachment fittings, and before further flight, do all applicable corrective actions, in accordance with the Accomplishment Instructions of De Havilland Aircraft of Canada Limited Service Bulletin 8-27-122, dated July 18, 2019. Repeat the inspection thereafter at intervals not to exceed 6 years. (4) Within 7 years since entry into service, or within 60 days after the effective date of this AD, whichever occurs later, do a detailed inspection for cracks and corrosion of the barrel nuts, having P/N DSC228-4, at the rudder pedal adjustment mechanism, and before further flight, do all applicable corrective actions, in accordance with the Accomplishment Instructions of De Havilland Aircraft of Canada Limited Service Bulletin 8-27-121, dated July 30, 2019. Repeat the inspection thereafter at intervals not to exceed 7 years.

This AD was prompted by reports of cracked barrel nuts at the wing front spar and horizontal stabilizer to vertical stabilizer joint, which was caused by corrosion from inadequate cadmium plating on the barrel nuts. The FAA is issuing this AD to address cracking and corrosion of the affected barrel nuts. The unsafe condition, if not addressed, could result in failed barrel nuts that could compromise the structural integrity of the airplane and could lead to loss of control of the airplane.

None.