Summary
We propose to supersede Airworthiness Directive (AD) 2017-12- 03, which applies to certain Pratt & Whitney Division (PW) PW2037, PW2037M, and PW2040 turbofan engines. AD 2017-12-03 requires installing a software standard eligible for installation and precludes the use of electronic engine control (EEC) software standards earlier than SCN 5B/ I. Since we issued AD 2017-12-03, software became available for additional PW engines models. This proposed AD would require installing a software standard eligible for installation and preclude the use of EEC software standards earlier than SCN 5B/I or SCN 27A. We are proposing this AD to address the unsafe condition on these products.