Airworthiness Directives; General Electric Company CF34-3A1, -3B, and -3B1 Turbofan Engines

This amendment supersedes an existing airworthiness directive (AD), that is applicable to General Electric Company (GE) CF34-3A1, - 3B, and -3B1 turbofan engines with scavenge screens part numbers (P/Ns) 4047T95P01 and 5054T86G02 installed in the B-sump oil scavenge system. That AD currently requires initial and repetitive visual inspections and cleaning of the B-sump scavenge screens. This amendment requires initial and repetitive visual inspections and cleaning of the B-sump scavenge screens until a screenless fitting is installed. This amendment is prompted by six reports of B-sump oil scavenge system failure causing engine in-flight shutdowns. The actions specified by this AD are intended to prevent B-sump scavenge screen blockage due to coking, which could result in ignition of B-sump oil in the secondary air system, fan drive shaft separation, and uncontained engine failure.