The FAA has adopted an Airworthy Directive (AD) for Pratt & Whitney Canada PT6A-114 and PT6A-114A turboprop engines. This AD requires initial and repetitive borescope inspections of the compressor turbine (CT) blades and removal from service of blades that fail inspection. According to the FAA “There have been a number of reported incidents where compressor turbine (CT) blades have failed in flight causing power loss and/or engine failure. Pratt & Whitney engineers have determined that high power and high temperature operations can cause the CT blades to crack or break due to “blade creep”. AD 2014-17-08 requires replacement of all CT blades during the next Hot section inspection (HSI) and every HSI thereafter.
P&W has developed a new CT blade airfoil made from a single crystal super alloy. This new CT blade has improved properties such as greater creep strength, axial thermal fatigue resistance and oxidation resistance. P&W is offering a “Special Program Allowance” for compressor turbine blade replacements. This allowance allows operators to take advantage of a 60% discount on new CT blades during engine overhaul and a 70% discount on CT blades during Hot Section Inspections (HSI). This program will terminate August 2016, so contact your Africair sales representative and order your new CT blades today.