Airworthiness Directive · Amendment 39-14570 · Pratt & Whitney Canada (PWC) PW535A Turboshaft Engines
Pratt & Whitney Canada (PWC) PW535A Turboshaft Engines
This AD applies to Pratt & Whitney Canada (PWC) PW535A engines with serial numbers lower than DC0241, and with hydromechanical fuel control (HFC) part number (P/N) 819735-4, 819735-5, or 819735-6 installed. These engine models are installed on, but not limited to, Cessna model 560 Citation (Encore) airplanes.
The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney Canada (PWC) PW535A turboshaft engines with serial numbers (SNs) lower than DC0241, and with hydromechanical fuel control (HFC) part number (P/N) 819735-4, 819735-5, or 819735-6 installed. This AD requires inspection and verification of the proper adjustment of the ratio unit setscrew adjustment of installed HFC units. This AD results from incidents of PW535A turboshaft engines experiencing lack of response to the power lever input during attempted engine acceleration, due to an incorrect adjustment of the HFC ratio unit setscrew. We are issuing this AD to prevent lack of engine response to power lever input, which could cause a single or dual engine in-flight shutdown event.
You are responsible for having the actions required by this AD performed within 50 flight hours time-in-service after the effective date of this AD, unless the actions have already been done.
(f) To ensure the HFC, P/N 819735-4, 819735-5, or 819735-6, ratio unit setscrew is properly adjusted, determine if the HFC serial number is listed in Table 1 of PWC Alert Service Bulletin (ASB) No. PW500-72-A30257, Revision 1, dated December 3, 2004.
(1) If the HFC's serial number is listed in Table 1, ensure the HFC ratio unit setscrew is properly adjusted by following the instructions contained in paragraphs 3 B, C, D, E, F, G, and H of PWC ASB No. PW500-72-A30257, Revision 1, dated December 3, 2004.
(2) If the HFC's serial number is not listed, this airworthiness directive is not applicable.
Compliance with the original version of PWC ASB No. PW500-72-A30257, dated December 2, 2003, before the effective date of this AD satisfies the requirements of this AD.
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.
