Airworthiness Directive · Amendment 39-17303 · Pratt & Whitney Canada Corp. Turboprop Engines
Pratt & Whitney Canada Corp. Turboprop Engines
This AD applies to all Pratt & Whitney Canada Corp. (P&WC) PW118, PW118A, PW118B, PW119B, PW119C, PW120, PW120A, PW121, PW121A, PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, PW127G, and PW127M turboprop engines, with the serial number (S/N) propeller shafts listed in P&WC Alert Service Bulletin (ASB) No. PW100-72-A21813, Revision 3, dated March 21, 2012, ASB No. PW100-72-A21802, Revision 4, dated March 16, 2012, and ASB No. PW100-72-A21798, Revision 5, dated March 20, 2012.
We are superseding an existing airworthiness directive (AD) for all Pratt & Whitney Canada Corp. (P&WC) PW118, PW118A, PW118B, PW119B, PW119C, PW120, PW120A, PW121, PW121A, PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, PW127G, and PW127M turboprop engines. That AD currently requires initial and repetitive inspections of certain serial numbers (S/Ns) of propeller shafts for cracks and removal from service if found cracked. This new AD requires the same actions, but requires removal from service of affected propeller shafts as mandatory terminating action to the repetitive inspections. This AD was prompted by reports of two propeller shafts found cracked at time of inspection during maintenance. We are issuing this AD to detect propeller shaft cracks, which could cause failure of the shaft, propeller release, and loss of control of the airplane.
(1) For propeller shafts with an S/N listed in Table 1 and Table 2 of P&WC ASB No. PW100-72-A21813, Revision 3, dated March 21, 2012:
(i) For engines not yet initially inspected per AD 2012-11-14 (77 FR 39624, July 5, 2012), before further flight, perform either an initial visual inspection or an initial ultrasonic inspection (UI) for cracks, in accordance with paragraphs 3.C.(1) through 3.C.(1)(a), and 3.C.(2) of P&WC ASB No. PW100-72-A21813, Revision 3, dated March 21, 2012, and Section 9 of P&WC Special Instruction (SI) P&WC No. 22-2012, R2, dated April 4, 2012.
(ii) If the visual inspection was performed, repeat the visual inspection within 50 engine flight hours (EFH) after the initial inspection, and thereafter within every 10 EFH, until the propeller shaft is removed from service.
(iii) If the UI was performed, repeat the UI at intervals not to exceed 1,000 EFH, until the propeller shaft is removed from service.
(2) If a crack is found during any of the inspections required by this AD, remove the propeller shaft from service before the next flight.
As mandatory terminating action to the repetitive inspections required by this AD:
(1) For propeller shafts with an S/N listed in Table 1 of P&WC ASB No. PW100-72-A21802, Revision 4, dated March 16, 2012, remove the propeller shafts from service before further flight.
(2) For affected S/N propeller shafts listed in Table 1 of P&WC ASB No. PW100-72-A21798, Revision 5, dated March 20, 2012, remove the propeller shafts from service within 6 months after the effective date of this AD.
(3) For affected S/N propeller shafts listed in Table 2 of P&WC ASB No. PW100-72-A21798, Revision 5, dated March 20, 2012, remove the propeller shafts from service within 12 months after the effective date of this AD.
(1) After the effective date of this AD, do not install any propeller shaft S/Ns listed in Table 1 of P&WC ASB No. PW100-72-A21802, Revision 4, dated March 16, 2012, into any engine.
(2) After the effective date of this AD, do not install any propeller shaft S/Ns listed in Table 1 and Table 2 of P&WC ASB No. PW100-72-A21798, Revision 5, dated March 20, 2012, into any engine.
(1) Initial inspections performed before the effective date of this AD using P&WC ASB No. PW100-72-A21813, Revision 3, dated March 21, 2012 or earlier revisions satisfy the initial inspection requirements of paragraph (f) of this AD. However, you must perform the repetitive inspection intervals specified in paragraph (f).
(2) Ultrasonic inspections performed before the effective date of this AD per Special Instruction P&WC 22-2012R2, dated April 4, 2012, or earlier revisions satisfy the requirements of paragraph (f) 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.
