EASA SIB NE-19-02: Pratt & Whitney PW4000 Engines - Low-Pressure Turbine Uncontainment

What to do

Operators and maintenance facilities should remove the affected P-flange bolts and replace them with the longer bolts and crushable spacers following Pratt & Whitney Service Bulletin PW4ENG 72-831. For engines PW4052, PW4056, PW4060, PW4152, PW4156A, PW4158, PW4460, or PW4462, it is recommended to perform the concurrent requirements in Service Bulletins PW4ENG 72-256 and PW4ENG 75-53 before or during the bolt replacement. No specific compliance deadlines are stated in the bulletin.

Summary

The Special Airworthiness Information Bulletin (SAIB) NE-19-02 issued by the FAA addresses potential low-pressure turbine (LPT) failures in Pratt & Whitney PW4000-94 model turbofan engines. These engines are installed on aircraft including Boeing 747, Boeing 767, Airbus A300, Airbus A310, and McDonnell Douglas MD-11. The bulletin informs operators and maintenance organizations about risks related to P-flange bolt fractures and nacelle penetration due to LPT failures.

What changed

SAIB NE-19-02 introduces awareness of the P-flange bolt failure issue and recommends replacing affected bolts with longer bolts and crushable spacers as detailed in Pratt & Whitney Service Bulletin PW4ENG 72-831 dated April 16, 2015. It also advises operators of certain PW4000 variants to comply with additional service bulletins PW4ENG 72-256 and PW4ENG 75-53 concurrently or prior to the bolt replacement. This bulletin does not mandate regulatory action but provides important maintenance recommendations.

Why it matters

This bulletin is critical for aviation professionals because it highlights a known engine component failure that could lead to debris exiting the engine nacelle, posing safety risks. Operators and maintenance teams must be aware of the recommended service bulletins to enhance engine containment and prevent potential in-flight incidents. Compliance with these recommendations helps maintain engine reliability and airworthiness without current regulatory mandates.