Airworthiness Directive · Amendment 39-18485 · Pratt & Whitney Division Turbofan Engines
Pratt & Whitney Division Turbofan Engines
(1) This AD applies to all Pratt & Whitney Division (PW) PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with a “-3” suffix, with one of the following installed:
(i) High-pressure compressor (HPC) 10th stage disk, part number (P/N) 51H710, with a serial number (S/N) listed in Table 1 of PW Alert Service Bulletin (ASB) PW4ENG A72-833, dated August 20, 2015; or
(ii) HPC 10th stage disk, P/N 53H976-06, with an S/N listed in Table 2 of PW ASB PW4ENG A72-833, dated August 20, 2015.
(2) This AD also applies to all PW PW4164, PW4168, PW4168A, PW4164C, PW4164C/B, PW4170, PW4168A-1D, PW4168-1D, PW4164-1D, PW4164C-1D, and PW4164C/B-1D turbofan engines with an HPC 10th stage disk, P/N 53H976-06, with an S/N listed Table 1 of PW ASB PW4G-100-A72-255, dated August 31, 2015, installed.
We are adopting a new airworthiness directive (AD) for certain Pratt & Whitney Division (PW) PW4000-94 inch and PW4000-100 inch model turbofan engines. This AD was prompted by a report of a crack found in the high-pressure compressor (HPC) 10th stage disk. This AD requires performing an ultrasonic inspection (USI) or an eddy current inspection (ECI) of the HPC 10th stage disk. We are issuing this AD to prevent failure of the HPC 10th stage disk, uncontained disk release, damage to the engine, and damage to the airplane.
(1) After the effective date of this AD, whenever the high-pressure turbine (HPT) or low-pressure turbine (LPT) is removed from the engine, perform an ultrasonic inspection (USI) of the HPC 10th stage disk for cracks. If the HPC 10th stage disk fails the USI, perform a follow-on eddy current inspection (ECI) or remove the disk from service and replace with a part eligible for installation.
(2) After the effective date of this AD, whenever the HPC front drum rotor disk assembly is removed from the engine, perform an ECI of the HPC 10th stage disk for cracks. Remove from service any HPC 10th stage disk that fails inspection and replace with a part eligible for installation. A USI as required by paragraph (e)(1) of this AD is not required if an ECI is performed.
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.
