Airworthiness Directive · Amendment 39-16087 · Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, and -17 Turbofan Engines
Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, and -17 Turbofan Engines
This AD applies to Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, and -17 turbofan engines, with 2nd stage fan blades, part number (P/N) 433802, 645902, 759902, 695932, 678102, or 746402, installed. These engines are installed on, but not limited to, Boeing 727, 737, and McDonnell Douglas DC-9 series airplanes.
The FAA is superseding an existing airworthiness directive (AD) for Pratt & Whitney JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, and -17 turbofan engines with 2nd stage fan blades, part number (P/N) 433802, 645902, 759902, 695932, 678102, or 746402, installed. That AD currently requires initial and repetitive ultrasonic inspection (UI) and fluorescent penetrant inspection (FPI) of those P/N 2nd stage fan blades. This AD replaces the required FPI with eddy current inspection (ECI) on all affected 2nd stage fan blades and maintains the requirement of UI of the blade root attachment on some of the affected 2nd stage fan blades. This AD also introduces an optional terminating action to the repetitive blade inspections for certain engine models. This AD results from reports of 10 fractures of 2nd stage fan blades since AD 87-14-01R1 became effective. We are issuing this AD to prevent uncontained failure of 2nd stage fan blades, which could result in damage to the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
For 2nd stage fan blades, P/N 678102 and P/N 746402, perform an eddy current inspection (ECI) of the blade pin-root holes for cracks, and for 2nd stage fan blades, P/Ns 433802, 645902, 759902, and 695932, perform an ECI of the blade pin-root holes and perform an ultrasonic inspection (UI) of the blade root attachment for cracks, as follows:
(1) Perform an inspection at the first disassembly of the 2nd stage fan rotor from the low-pressure (LP) compressor after accumulation of 3,000 cycles-in-service (CIS) since the last inspection of the blade root attachment, not to exceed 10,000 CIS since last inspection.
(2) If the 2nd stage fan blades were new at their last installation onto the 2nd stage fan disk, inspect at the first disassembly of the 2nd stage fan rotor from the LP compressor after accumulating 3,000 cycles-since-new (CSN), not to exceed 10,000 CSN.
(3) Thereafter, inspect the 2nd stage fan blades at each disassembly of the 2nd stage fan rotor from the LP compressor after accumulating 3,000 CIS, not to exceed 10,000 CIS since the last inspection.
(4) Guidance on performing ECIs and UIs of the 2nd stage fan blade pin-root holes and blade root attachments can be found in Pratt & Whitney Maintenance Advisory Notice MAN-JT8D-1-08. Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860) 565-8770; fax (860) 565-4503, for a copy of this service information.
(5) Remove from service before further flight any 2nd stage fan blades that are found cracked.
For JT8D-9, -9A, -11, -15, and -17 engines, as optional terminating action to the repetitive inspections required by this AD, replace the affected 2nd stage fan blades with redesigned 2nd stage fan blades using Pratt & Whitney Service Bulletin No. 5866, Revision 2, dated October 20, 1998.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
