Airworthiness Directive · Amendment 39-21588 · Turbine engine compressor section
Engine Alliance Turbofan Engines
This AD applies to Engine Alliance (EA) GP7270 and GP7277 model turbofan engines with low-pressure compressor (LPC) 1st-stage fan blades, part number (P/N) 5700531, 5702931, 5702931CL1, or 5702931CL2, installed.
The FAA is superseding Airworthiness Directive (AD) 2019-25- 13, which applied to all Engine Alliance (EA) GP7270 and GP7277 model turbofan engines with a certain low-pressure compressor (LPC) 1st-stage fan blade installed. AD 2019-25-13 required an ultrasonic inspection of the affected LPC 1st-stage fan blades and replacement of any affected LPC 1st-stage fan blade that fails the inspection. This AD lowers the initial inspection threshold and requires repetitive ultrasonic inspections on affected LPC 1st-stage fan blades. This AD was prompted by a report of an in-flight shutdown (IFSD) of an engine due to the fracture of multiple LPC 1st-stage fan blades. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within the compliance time specified in Table 1 to paragraph (g)(1) of this AD, perform an ultrasonic inspection of the LPC 1st-stage fan blades using the Accomplishment Instructions, “For Fan Blades Installed In An Engine,” paragraph 1, or “For Fan Blades Not Installed In An Engine,” paragraph 1, as applicable, of EA Alert Service Bulletin (SB) EAGP7-A72-444, dated November 18, 2020.
(2) Thereafter, at intervals not to exceed 800 flight cycles since last inspection, perform an ultrasonic inspection of the LPC 1st-stage fan blades using the Accomplishment Instructions, “For Fan Blades Installed In An Engine,” paragraph 1, or “For Fan Blades Not Installed In An Engine,” paragraph 1, as applicable, of EA Alert SB EAGP7-A72-444, dated November 18, 2020.
(3) If an ultrasonic inspection of an LPC 1st-stage fan blade results in a rejectable ultrasonic indication, remove the LPC 1st-stage fan blade from service and replace with a part eligible for installation before further flight.
Note 1 to paragraph (g)(3): Guidance on determining a rejectable ultrasonic indication can be found in GP7000 1st Stage LPC Rotor (Fan) Blade Assembly Airfoil Ultrasonic Inspection for Cracks (Fan Blade Installed or Uninstalled), NDIP-1205, Revision C, dated September 15, 2020.
