Airworthiness Directives; Boeing Model 727 Series Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to all Boeing Model 727 series airplanes. This action requires repetitive pre-modification inspections to detect cracks in the forward support fitting of the number 1 and number 3 engines; and repair, if necessary. This AD also provides for an optional high frequency eddy current (HFEC) inspection, and, if possible, modification of the fastener holes; and various follow-on actions. Accomplishment of these optional actions would constitute terminating action for the repetitive pre-modification inspections. This amendment is prompted by reports indicating that fatigue cracks were found in the forward support fitting of the number 1 and number 3 engines. The actions specified in this AD are intended to detect and correct such fatigue cracking, which could result in failure of the support fitting and consequent separation of the engine from the airplane.