What Happened
Federal Aviation Administration Mandates Repetitive Inspections
The Federal Aviation Administration has issued an airworthiness directive for Boeing 747-400 and -8 series airplanes, mandating repetitive inspections for damage of transfer pump housing inlet check valves and transfer pump motor impeller inlet adapters. The directive, effective December 7, 2026, aims to address the development of an ignition source within the horizontal stabilizer fuel tank, which could result in a fuel tank explosion. The FAA estimates that this directive affects 31 airplanes of U.S. registry, with estimated costs to comply ranging from $1,530 to $20,170 per inspection cycle. This directive was first reported in the Federal Register.