Airworthiness Directives; Pratt & Whitney Canada Corp. Turboshaft Engines

The FAA is adopting a new airworthiness directive (AD) for all Pratt & Whitney Canada Corp. (P&WC) PW210A and PW210S model turboshaft engines. This AD was prompted by a report from the manufacturer that the Automated Damage Tracking System (ADTS) may under-count the number of cycles accrued by the impeller and the high-pressure compressor (HPC) rotor. This AD requires use of the manual low-cycle fatigue (LCF) counting method in place of the ADTS counting method to determine the number of cycles accrued by the impeller and HPC rotor. The FAA is issuing this AD to address the unsafe condition on these products.