Airworthiness Directive · Amendment 39-22452 · Turbine section
Engine Alliance Engines
This AD applies to Engine Alliance Model GP7270, GP7272, and GP7277 engines with an installed high-pressure turbine (HPT) interstage seal having part number (P/N) 2047M99P02 and serial number (S/N) BTB71863 or BTB86871.
The FAA is adopting a new airworthiness directive (AD) for certain Engine Alliance (EA) Model GP7270, GP7272, and GP7277 engines. This AD was prompted by a manufacturer investigation that revealed that certain high-pressure turbine (HPT) interstage seals were manufactured from material suspected to contain iron inclusion. This AD requires replacement of the affected HPT interstage seals. The FAA is issuing this AD to address the unsafe condition on these products.
At the next piece-part exposure of the affected HPT interstage seal or before the affected HPT interstage seal exceeds 4,200 cycles since new, whichever occurs first after the effective date of this AD, remove the affected HPT interstage seal from service and replace with a part eligible for installation.
(1) For the purpose of this AD, a “part eligible for installation” is any HPT interstage seal that does not have a P/N and S/N identified in paragraph (c) of this AD.
(2) For the purpose of this AD, “piece-part exposure” is when the affected part is removed from the engine and completely disassembled.
