Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain Pratt & Whitney Division (PW) PW4158 turbofan engines. This AD was prompted by several reports of high cycle fatigue (HCF) cracks found in the fuel nozzle supply manifold. This AD requires replacement of the affected fuel nozzles and fuel nozzle manifold supply assemblies with parts eligible for installation. This AD also requires installation of new brackets and clamps on the fuel nozzle supply manifold assemblies. We are issuing this AD to address the unsafe condition on these products.