AD 2011-14-07

final rule
Data completeness: 70%

Airworthiness Directives; Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Engines

AD Number
2011-14-07
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. FAA-2010-1095
FR Citation
76 FR 47056

Applicability

TypeManufacturerModelDetails
aircraft Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Airworthiness Directives; Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Engines

Unsafe Condition

Multiple shop findings of cracked 15th stage high-pressure compressor (HPC) disks. Cracks could propagate into the bolt holes, leading to disk failure, uncontained engine failure, and damage to the airplane.

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

Required Actions

Remove the 15th stage HPC disk before accumulating 12,000 cycles since new (CSN). For disks exceeding 12,000 CSN after the effective date, use a drawdown plan with borescope inspection (BSI) or eddy current inspection (ECI) of the rim for cracks. If cracks are detected, remove the disk from service before further flight.

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

Compliance Time

Within 12,000 cycles since new (CSN) or within 2,135 cycles-in-service (CIS) after the effective date for disks exceeding 9,865 CSN on the effective date.

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

Affected Aircraft

Pratt & Whitney PW4074 and PW4077 turbofan engines with 15th stage HPC disks, part number 55H615, installed.

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

Source: Official FAA Source ↗

Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.