Boeing 747s: FAA Says Shield Water Lines from Leaks Now
Published Date: 2/14/2025
Rule
Summary
If you own or operate certain Boeing 747 models, listen up! The FAA found a problem where water lines near important electronics could leak and cause warning messages. Starting March 21, 2025, airlines must install protective covers and shields on these water lines to keep everything safe and sound—fixes that help avoid costly repairs and keep flights flying smoothly.
Analyzed Economic Effects
4 provisions identified: 3 benefits, 1 costs, 0 mixed.
Mandatory water-line shields for certain 747s
If you own or operate certain Boeing Model 747-400, 747-400F, 747-8F, or 747-8 airplanes, you must install protective items (conduits, envelope assemblies, spray shields, deflector shields, and/or shrouds) on exposed potable water supply lines at specified locations. The AD is effective March 21, 2025, and the FAA estimates it affects 178 U.S.-registered airplanes with an estimated maximum cost per airplane of up to $6,850 (up to 22 work-hours at $85/hour = up to $1,870 labor plus up to $4,980 parts), and a total U.S. operators cost up to $1,219,300.
Reduces risk of electronics failure from water leaks
The rule responds to reported separations of a potable water fitting that allowed water into the main electronics center, which could adversely affect multiple essential electronics and line replaceable units and could lead to loss of continued safe flight and landing. The AD requires the protective installations to address that unsafe condition on affected 747-400 and 747-8 series airplanes.
Manufacturer may cover some compliance costs
The manufacturer (Boeing) stated that some or all of the costs to comply with this AD may be covered under warranty, which could reduce the cost impact on affected operators.
FAA finds no significant small-entity economic impact
The FAA certified that this AD will not have a significant economic impact, positive or negative, on a substantial number of small entities under the Regulatory Flexibility Act.
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