airworthiness · Rule · Final rule. · Published 2011-12-06 · Effective 2012-01-10 · 76 FR 76027
Document
Document number
2011-31177
Federal Register citation
76 FR 76027
Type
Rule
Action
Final rule.
Category
airworthiness
Manufacturer
Pratt & Whitney Division (PW) PW4000 Series Turbofan
Publication date
2011-12-06
Effective date
2012-01-10
FAA docket
Docket No. FAA-2011-0733
Abstract
We are adopting a new airworthiness directive (AD) for certain PW4000 turbofan engines. This AD was prompted by an updated low-cycle fatigue (LCF) life analysis performed by PW. This AD requires removing certain part number (P/N) high-pressure turbine (HPT) stage 1 and HPT stage 2 airseals and HPT stage 1 airseal rings before their published life limit and establishes a new lower life limit for these parts. We are issuing this AD to prevent failure of these parts, which could lead to an uncontained engine failure and damage to the airplane.