Transport i infrastruktura · 1.12.2004
Airworthiness Directives; Boeing Model 747 Airplanes
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 747 airplanes. This proposed AD would require repetitive tests to detect hot air leaking from the trim air diffuser ducts or sidewall riser duct assemblies (collectively referred to in this proposed AD as "TADDs"), related investigative actions, and corrective actions if necessary. This proposed AD also would provide an optional terminating action for the repetitive tests. This proposed AD is prompted by reports of deteriorating sealants both inside and outside the center wing fuel tank due to heat damage from leaking TADDs. We are proposing this AD to prevent leakage of fuel or fuel vapors into areas where ignition sources may be present, which could result in a fire or explosion.