Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for all Pratt & Whitney Canada Corp. (P&WC) PT6A-114 and PT6A-114A turboprop engines. This proposed AD was prompted by several incidents of compressor turbine (CT) blade failure, including two fatalities, resulting in power loss and in-flight shutdown (IFSD) of the engine. This proposed AD would require initial and repetitive borescope inspections (BSIs) of CT blades, and the removal from service of blades that fail inspection. We are proposing this AD to prevent failure of CT blades, which could lead to damage to the engine or to the airplane.