Airworthiness Directives; Rolls-Royce Deutschland (Formerly Rolls-Royce plc) Models Tay 650-15 and 651-54 Turbofan Engines

摘要

The FAA proposes to supersede an existing airworthiness directive (AD) for Rolls-Royce Deutschland (formerly Rolls-Royce plc) (RRD) models Tay 650-15 and 651-54 turbofan engines. That AD currently requires borescope inspection of the high pressure compressor (HPC) stage 12 disc assembly to detect damage caused by HPC outlet guide vane (OGV) retaining bolt failure, and replacement of unserviceable parts with serviceable parts. That AD also requires as terminating action, the incorporation of a new design retention arrangement for the HPC OGV to prevent HPC OGV retaining bolt failure. This proposed AD would require the same actions but extends the terminating action compliance time for Tay 650-15 engines. This proposed AD would also include references to later revisions of two of the applicable RRD service bulletins (SBs). This proposed AD results from findings that the terminating action compliance time for Tay 650-15 engines can be extended. We are proposing this AD to prevent an uncontained failure of the HPC stage 11/12 disc spacer, which could result in damage to the airplane.