AD 2007-26-20

final rule
Data completeness: 70%

Airworthiness Directives; Pratt & Whitney (PW) PW4164, PW4168, and PW4168A Turbofan Engines

AD Number
2007-26-20
Status
final_rule
Effective Date
Product Category
engine
Docket
FAA-2007-27230
FR Citation
Federal Register: January 3, 2008 (Volume 73, Number 2)

Applicability

TypeManufacturerModelDetails
engine Pratt & Whitney Division PW4164 Airworthiness Directives; Pratt & Whitney (PW) PW4164, PW4168, and PW4168A Turbofan Engines
engine Pratt & Whitney Division PW4168 Airworthiness Directives; Pratt & Whitney (PW) PW4164, PW4168, and PW4168A Turbofan Engines
engine Pratt & Whitney Division PW4168A Airworthiness Directives; Pratt & Whitney (PW) PW4164, PW4168, and PW4168A Turbofan Engines

Unsafe Condition

Improperly manufactured LPT stage 4 disks, part number 51N404, may result in low-cycle fatigue (LCF) leading to uncontained engine failure.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Remove certain LPT stage 4 disks listed by serial number at the next piece-part exposure or within 7,500 cycles-since-new (CSN).

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 7,500 cycles-since-new or at the next piece-part exposure, whichever occurs first.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Pratt & Whitney PW4164, PW4168, and PW4168A turbofan engines with LPT stage 4 disks (P/N 51N404) as specified in the AD.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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