Airworthiness Directive · Amendment 39-12698 · Pratt & Whitney JT9D-7R4 Series Turbofan Engines
Pratt & Whitney JT9D-7R4 Series Turbofan Engines
This airworthiness directive (AD) is applicable to Pratt & Whitney (PW) JT9D-7R4D, -7R4D1, -7R4E, -7R4E1, -7R4E4, -7R4G2, and 7R4H1 series turbofan engines with LPT 5th stage disks, part numbers (P/N's) 787905, 787905-001, and 798305 installed. These engines are installed on, but not limited to Airbus Industrie A300 and A310 series, and Boeing 747 and 767 series airplanes.
This amendment adopts a new airworthiness directive (AD), that is applicable to Pratt & Whitney (PW) JT9D-7R4 series turbofan engines. This amendment requires a one-time inspection of low pressure turbine (LPT) 5th stage disks for evidence of blend repairs and mechanical damage, and replacement of the affected disks based on the extent of those repairs and damage. This amendment is prompted by a report of a PW JT9D-7R4G2 turbofan engine that experienced an uncontained failure of the LPT 5th stage disk. The actions specified by this AD are intended to prevent uncontained failure of the LPT 5th stage disk, due to incomplete blend repairs, resulting in in-flight shutdown and damage to the airplane.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
