Airworthiness Directives; Boeing Model 727-100 Series Airplanes Modified in Accordance With Supplemental Type Certificate (STC) SA8472SW

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 727-100 series airplanes. This action requires a revision to the Airplane Flight Manual (AFM) to prohibit stabilized operation between 60 and 75 percent N1 speed during ground operations in reverse or forward thrust. This amendment is prompted by a report that, during preparation for takeoff, a transport category airplane equipped with Rolls-Royce Tay 650-15 engines sustained an engine fan blade failure, followed by an engine fire. The actions specified in this AD are intended to prevent uncontained failure of engine fan blades due to high cycle fatigue cracking, which could result in loss of thrust from the affected engine and secondary damage to the airplane and/or fire.