Airworthiness Directives; Rolls-Royce, plc. Models Tay 650-15 and 651-54 Turbofan Engines

This amendment adopts a new airworthiness directive (AD) that is applicable to Rolls-Royce, plc (RR) models Tay 650-15 and 651-54 turbofan engines. This action 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. This action 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 amendment is prompted by service reports of cracked HPC stage 11/12 disc spacers. The actions specified in this AD are intended to prevent an uncontained failure of the HPC stage 11/12 disc spacer, which could result in damage to the airplane.