Airworthiness Directives; Boeing Model 757 Equipped With Pratt & Whitney Model PW2000 Series Engines

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 757 series airplanes. This action requires a revision to the FAA-approved Airplane Flight Manual to include procedures to perform periodic engine run-ups during ground operation in icing conditions in order to shed ice before it accumulates, sheds, and is ingested into the engine, which could cause damage to the core of the engine. This action provides procedures for a visual check to detect ice build-up on the first stage of the low pressure compressor (LPC) stator and removal of any ice, as necessary. This amendment is prompted by reports of damage to the high pressure compressor of the engines due to ice ingestion. The actions specified in this AD are intended to prevent damage to engines due to the ingestion of ice into the compressor, which can result in the loss of power from the affected engine.