AD 2012-18-14

final rule
Data completeness: 80%

Airworthiness Directives; Pratt & Whitney Canada, Auxiliary Power Units

AD Number
2012-18-14
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2012-0071
FR Citation
77 FR 57001

Applicability

TypeManufacturerModelDetails
aircraft Boeing 747-400 Airworthiness Directives; Pratt & Whitney Canada, Auxiliary Power Units
engine Pratt & Whitney Canada Airworthiness Directives; Pratt & Whitney Canada, Auxiliary Power Units

Unsafe Condition

High-pressure turbine blade fracture leading to separation of the rear gas generator case and release of high energy debris.

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

Required Actions

Modify the rear gas generator case, exhaust duct support, and turbine exhaust duct flanges.

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

Compliance Time

Within 42 months after the effective date of the AD or the first time the APU or module is at a maintenance facility that can perform the modifications, whichever occurs first.

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

Affected Aircraft

Pratt & Whitney Canada PW901A auxiliary power units (APUs) approved under Technical Standard Order TSO-C77A and installed on, but not limited to, Boeing 747-400 series airplanes.

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

Source: Official FAA Source ↗

Retrieved: Apr 4, 2026

Rights: U.S. Government Public Domain

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View Official Source ↗ Find More ADs for Boeing 747-400

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