AD 2011-25-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Pratt | & Whitney Division (PW) PW4000 Series Turbofan | Airworthiness Directives; Pratt & Whitney Division (PW) PW4000 Series Turbofan Engines |
Unsafe Condition
failure of the high-pressure turbine (HPT) stage 1 airseal, part number (P/N) 50L879, HPT stage 2 airseal, P/N 53L030, or HPT stage 1 airseal ring, P/N 50L664, which could lead to an uncontained engine failure and damage to the airplane.
Required Actions
remove the stage 1 HPT airseal, P/N 50L879, at the next piece-part exposure after the effective date of this AD or before accumulating the number of cycles listed in Table 1 of this AD, whichever occurs later.
Compliance Time
Within 12,600 cycles-since-new (CSN) for engines listed in paragraph (c)(1) of the Applicability Section of this AD, within 13,900 CSN for engines listed in paragraph (c)(2)(i) of the Applicability Section of this AD, and within 18,900 CSN for engines listed in paragraph (c)(2)(ii) of the Applicability Section of this AD.
Affected Aircraft
Pratt & Whitney Division (PW) turbofan engines, with high-pressure turbine (HPT) stage 1 airseal, part number (P/N) 50L879; HPT stage 2 airseal, P/N 53L030; or HPT stage 1 airseal ring, P/N 50L664, installed on PW4000-100'' engines, PW4000-94'' engines with certain engine models and modifications.
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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