Airworthiness Directive · Amendment 39-13806 · Pratt & Whitney Canada Models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G Turboprop Engines
Pratt & Whitney Canada Models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G Turboprop Engines
This AD applies to Pratt & Whitney Canada (PWC) models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G turboprop engines, with mechanical fuel controls (MFCs), part numbers (P/Ns) 3244841-21, 3244853-17, 3244855-15, 3244857-14, 3244858-23, 3244871-5, 3244873-4, and 3244874-4, installed. These engines are installed on, but not limited to, Aerospatiale ATR 42 and ATR 72, BAE Systems (Operations) Limited ATP, Bombardier Inc. DHC-8-200 series, DHC-8-300 series, CL-215T, and CL-415, Construcciones Aeronauticas, S.A. (CASA) C-295, Fokker Aircraft B.V. F27 Mark 050, and Mark 060 airplanes.
The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney Canada (PWC) models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G turboprop engines. This AD requires initial and repetitive gap inspections of the bypass valve cover, on certain part number (P/N) mechanical fuel controls (MFCs), and replacement of those MFCs as mandatory terminating action to the repetitive inspections. This AD is prompted by sixteen reports of loss of engine throttle response and overspeed, eight of which resulted in in-flight shutdown. We are issuing this AD to prevent loss of throttle response and overspeed, resulting in engine in-flight shutdown.
Compliance with this AD is required as indicated, unless already done.
Within 500 hours time-in-service (TIS) after the effective date of the AD, perform a gap inspection between the MFC bypass valve cover and the MFC main body, and disposition the MFC. Follow paragraphs 5.0 through 5.3 of Honeywell Service Information Bulletin (SIB) No. 82, dated September 14, 2001, to do the inspection and MFC disposition.
At intervals of 1,500 hours TIS from the last gap inspection, perform repetitive gap inspections between the MFC bypass valve cover and the MFC main body and disposition the MFC. Follow paragraphs 5.0 through 5.3 of Honeywell SIB No. 82, dated September 14, 2001, to do the inspection and MFC disposition.
Within 4,500 hours TIS or 24 months from the effective date of this AD, whichever occurs first, replace the MFC with an MFC not having a P/N listed in paragraph (c) of this AD.
(i) Replacement of the MFC with an MFC whose P/N is not listed in paragraph (c) of this AD constitutes mandatory terminating action to the repetitive inspection requirements specified in paragraph (g) of this AD. Information on new design replacement MFCs can be found in PWC Service Bulletin No. PW100-72-21562, Revision 2, dated December 7, 2000.
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.
