# Proposed AD FAA-2010-0725: Pratt & Whitney PW4000 Series Turbofan Engines

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2010-24-09
- Products: Pratt & Whitney Division
- Product type: Engine
- Action: Notice of proposed rulemaking (NPRM); correction.
- Published: July 29, 2010, 75 FR 44725
- Comments due: August 1, 2010
- Became: [AD 2010-24-09](https://openairdocs.org/ad/2010-24-09)
- Docket: FAA-2010-0725 (https://www.regulations.gov/docket/FAA-2010-0725, where comments are filed)
- Project: 2010-NE-18-AD
- FR document: 2010-18628
- Official PDF: https://openairdocs.org/files/sha256/ad/32/ad3236aa9248038173cacfa4f5798459cda45b47c24e87834ff02e547e828557 (from https://www.govinfo.gov/content/pkg/FR-2010-07-29/pdf/2010-18628.pdf)
- Federal Register: https://www.federalregister.gov/documents/2010/07/29/2010-18628/airworthiness-directives-pratt-and-whitney-pw4000-series-turbofan-engines-correction
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E97F91B0AF8995AC8625776F003F6731.0001
- Page: https://openairdocs.org/proposed/FAA-2010-0725

## Summary

The FAA proposes to adopt a new airworthiness directive (AD) for Pratt & Whitney PW4000 series turbofan engines. This proposed AD would require a one-time visual inspection of the No. 3 bearing oil pressure tube, part number (P/N) 51J041-01, P/N 50J604-01, or P/N 50J924-01. Tubes that are found cracked or repaired would be required to be removed from service. This proposed AD would also prohibit repaired tubes from being installed. This proposed AD results from one report of a repaired No. 3 bearing oil tube that caused an engine in- flight shutdown, seven reports of repaired No. 3 bearing oil pressure tubes found cracked that led to unscheduled engine removals, and one report of a test cell event from a repaired tube that cracked. We are proposing this AD to prevent cracking of No. 3 bearing oil pressure tubes which could result in internal oil fire, failure of the high- pressure turbine (HPT) disks, uncontained engine failure, and damage to the airplane.

## Notices in this docket

- Jul 29, 2010: Notice of proposed rulemaking (NPRM); correction. (first notice), FR document 2010-18628, comments due Aug 1, 2010 (https://www.federalregister.gov/documents/2010/07/29/2010-18628/airworthiness-directives-pratt-and-whitney-pw4000-series-turbofan-engines-correction)

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