EASA AD US-2022-16-09
Wings - Center Fuel Tank Fastener Locations - Preparation of Adequate Sealant Adhesion
Summary
The Federal Aviation Administration's Airworthiness Directive 2022-16-09 addresses certain Boeing 737-8 airplanes. It requires preparation and sealing of specific fastener locations in the center fuel tank where sealant adhesion may be compromised due to cap sealing over a black ink stripe with a clear overcoat. This condition could affect lightning protection and increase the risk of fuel tank ignition during a lightning strike.
What Changed
This new airworthiness directive introduces mandatory surface preparation and complete encapsulation of discrepant fastener locations with approved production sealant to ensure adequate adhesion. It also adds an optional method allowing removal of existing sealant and black ink stripe before resealing to accommodate inspection and maintenance procedures. The directive clarifies the unsafe condition by detailing the failure sequence leading to potential fuel tank ignition.
Why It Matters
This directive is critical for operators and maintenance personnel to prevent compromised lightning protection in the center fuel tank, which could lead to fuel vapor ignition and explosion. Ensuring proper sealant adhesion maintains the structural integrity and safety of the aircraft. Compliance helps avoid costly repairs and enhances overall flight safety for Boeing 737-8 operators.
What To Do
Affected operators must prepare the specified fastener surface areas and apply approved sealant as detailed in Boeing Special Attention Requirements Bulletin 737-57-1352 RB. They may optionally remove existing sealant and black ink stripe before resealing to facilitate inspections. Compliance with this directive is required by October 20, 2022.
AI-generated summary from official EASA source document. Always verify against the original.