Action
Final rule.
Summary
The FAA is superseding Airworthiness Directive (AD) 2019-21-11 and AD 2020-07-02. AD 2019-21-11 applied to all Pratt & Whitney (PW) PW1519G, PW1521G, PW1521G-3, PW1521GA, PW1524G, PW1524G-3, PW1525G, PW1525G-3, PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A model turbofan engines. AD 2020-07-02 applied to all PW PW1519G, PW1521G, PW1521G-3, PW1521GA, PW1524G, PW1524G-3, PW1525G, and PW1525G-3 model turbofan engines. AD 2019-21-11 required initial and repetitive borescope inspections (BSIs) of the low-pressure compressor (LPC) rotor 1 (R1) and, depending on the results of the inspections, replacement of the LPC. AD 2020-07-02 required the removal from service of certain electronic engine control (EEC) full authority digital electronic control (FADEC) software and the installation of a software version eligible for installation. This AD continues to require repetitive BSIs of certain LPC R1s until replacement of EEC FADEC software with the updated software. This AD also requires a BSI after installation of the updated EEC FADEC software if certain Onboard Maintenance Message fault codes are displayed and meet specified criteria. The FAA is issuing this AD to address the unsafe condition on these products.