Summary
The Federal Aviation Administration (FAA) proposes to adopt a new airworthiness directive (AD) that is applicable to Pratt & Whitney Canada (PWC) models PW118, PW118A, PW118B, PW119B, PW119C, PW120, PW120A, PW121, PW121A, PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126, PW126A, PW127, PW127B, PW127E, PW127F, PW127G, PW127H, and PW127J turboprop engines. This proposal would require replacing certain part number (P/N) fuel heaters with redesigned fuel heaters. This proposal is prompted by several field incidents in which one or more of the three studs that attach the fuel filter bowl to the fuel heater have been partially or completely pulled free of the fuel heater housing. The actions specified by the proposed AD are intended to prevent the separation of the fuel filter bowl from the fuel heater, which could result in a pressurized fuel leak and possible engine fire.