Airworthiness Directives; Pratt & Whitney Canada PW206B, PW206C, PW206E, PW207D, and PW207E Turboshaft Engines

The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney Canada (PWC) PW206B engines that have incorporated PWC Service Bulletin (SB) No. 28119, and PW206C, PW206E, PW207D, and PW207E turboshaft engines. This AD requires checking the automatic low-cycle- fatigue (LCF) counting data made by the engine Data Collection Unit (DCU) on installed engines, and validating proper DCU automatic LCF counting before an engine is installed. This AD results from two reports of irregular LCF counting, observed between engines on the same helicopter, during weekly recording of LCF data in the engine log books. We are issuing this AD to prevent critical rotating parts from exceeding published life limits, which could result in uncontained engine failure and possible loss of the helicopter.