EASA AD US-2019-23-12
Wings - Fuel Tanks - Modification
Summary
Federal Register Volume 84, Number 236 (2019-23-12) is a final rule airworthiness directive issued by the FAA that applies to all Boeing 737-300, -400, and -500 series airplanes. It addresses fuel system safety by requiring modifications to the fuel tanks and associated components to prevent potential ignition sources. The directive mandates specific maintenance actions including applying sealant to fuel tank fasteners, replacing wire bundle clamps external to the fuel tanks, and installing Teflon sleeving under these clamps.
What Changed
This new airworthiness directive introduces mandatory modifications to the fuel tank systems of Boeing 737 Classic series airplanes. It requires operators to apply sealant to fasteners inside the fuel tanks, replace certain wire bundle clamps outside the tanks, and install Teflon sleeving under the clamps to mitigate ignition risks. The directive also clarifies that installation of Supplemental Type Certificate ST01219SE does not affect compliance with these requirements.
Why It Matters
This directive is critical for aviation professionals as it addresses a potential ignition source inside the fuel tanks that could lead to fuel tank fires or explosions, posing a severe safety risk. Operators, maintenance, and compliance teams must ensure these modifications are completed to maintain airworthiness and regulatory compliance. Failure to comply could result in unsafe operating conditions and regulatory penalties.
What To Do
Operators of Boeing 737-300, -400, and -500 series airplanes must comply with the directive by performing the required fuel tank modifications, including applying sealant, replacing clamps, and installing Teflon sleeving. The compliance deadline for these actions is January 13, 2020. Maintenance teams should reference Boeing Alert Service Bulletin 737-57A1321, dated February 8, 2019, for detailed procedures and ensure documentation is updated accordingly.
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