Airworthiness Directives; Pratt & Whitney PW4000 Series Turbofan Engines.
airworthiness · Rule · Final rule, request for comments. · Published 2000-12-14 · Effective 2000-12-29 · 65 FR 78083
Document
Document number
00-31537
Federal Register citation
65 FR 78083
Type
Rule
Action
Final rule, request for comments.
Category
airworthiness
Manufacturer
Pratt & Whitney PW4000 Series Turbofan
Publication date
2000-12-14
Effective date
2000-12-29
FAA docket
Docket No. 2000-NE-43-AD
Abstract
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Pratt & Whitney (PW) PW4000 turbofan engines with the current design low pressure turbine (LPT) 4th stage air seal installed. This action requires, based on engine model, replacement of the current design seal with a new design seal, or with a modified seal. This amendment is prompted by reports of cracks in LPT 4th stage air seals. The actions specified by this AD are intended to reduce stresses that could lead to LPT 4th stage air seal cracking, resulting in seal fracture, uncontained engine failure, and damage to the airplane.