Federal Register #2026-11217

FAA Airworthiness Directive: Inspection and Maintenance of Barrel Nuts on De Havilland DHC8 Aircraft

This opportunity concerns a Federal Aviation Administration (FAA) airworthiness directive for De Havilland Aircraft of Canada Limited DHC8 airplanes: - Government Buyer: - Federal Aviation Administration (FAA) - OEMs Highlighted: - De Havilland Aircraft of Canada Limited (current type certificate holder) - Bombardier, Inc. (previous type certificate holder) - Products/Services Requested: - Repetitive detailed inspections for cracking and corrosion of barrel nuts at multiple structural locations on DHC8 aircraft - Corrective actions including repair or replacement of affected barrel nuts - Specific barrel nut part numbers: DSC2284 and DSC2285 - Replacement barrel nut part numbers: B02030734 and B02030735 - Inspections and corrective actions must follow De Havilland service bulletins: 80511, 827121, 827122, 840502, 842773 - Notable Requirements: - Applies to all DHC8 models (various series) - Inspections required at intervals (every 6 or 7 years, or at windshield replacement) - Use of OEM-approved materials and procedures is mandatory - Estimated compliance cost per airplane is up to $1,105 - Affects 91 U.S.-registered airplanes - Aims to prevent structural failure and loss of control due to corroded or cracked barrel nuts

Description

This final rule airworthiness directive (AD) applies to all De Havilland Aircraft of Canada Limited Model DHC8 airplanes. It was prompted by reports of cracked barrel nuts at the wing front spar and horizontal stabilizer to vertical stabilizer joint caused by corrosion from inadequate cadmium plating. The AD requires repetitive inspections for cracking and corrosion of the affected barrel nuts and applicable corrective actions to address the unsafe condition. The AD is effective July 9, 2026, and aims to prevent failed barrel nuts that could compromise structural integrity and lead to loss of control of the airplane.

View original listing