AD 2013-15-09
Effective 09/17/2013 · Published 08/13/2013
Airworthiness Directives; Pratt & Whitney Division Turbofan Engines
Summary
We are adopting a new airworthiness directive (AD) for all Pratt & Whitney Division (PW) turbofan engine model PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 with a certain second- stage high-pressure turbine (HPT) air seal part number installed. This AD was prompted by discovery of cracks in second-stage HPT air seals. This AD requires inspection and removal from service of HPT air seals that fail…