Airworthiness Directives; Rolls-Royce plc RB211 Trent 768-60, 772-60, and 772B-60 Series Turbofan Engines

This amendment adopts a new airworthiness directive (AD) that is applicable to Rolls-Royce plc RB211 Trent 768-60, 772-60, and 772B- 60 series turbofan engines. This action requires initial and repetitive visual inspections for flank wear on intermediate pressure turbine (IPT) shaft splines and intermediate pressure compressor (IPC) rear stub shaft splines. Components that show excessive flank wear must be replaced with serviceable parts. This amendment is prompted by reports of worn IPT shaft splines discovered at overhaul. The actions specified in this AD are intended to prevent IPT and IPC shaft spline flank wear, which could result in loss of drive between the IPT and IPC, leading to an IPT overspeed and possible disk burst, uncontained engine failure, and potential damage to the aircraft.