Airworthiness Directive · Amendment 39-18250 · Pratt & Whitney Turbofan Engines
Pratt & Whitney Turbofan Engines
This AD applies to all Pratt & Whitney (PW) PW4164-1D, PW4168-1D, PW4168A-1D and PW4170 engines; and all PW4164, PW4168, and PW4168A turbofan engines that have incorporated either PW Service Bulletin (SB) No. PW4G-100-72-214, dated December 15, 2011 or PW SB No. PW4G-100-72-219, Revision 1, dated October 5, 2011.
We are adopting a new airworthiness directive (AD) for all Pratt & Whitney (PW) PW4164-1D, PW4168-1D, PW4168A-1D and PW4170 engines, and certain PW4164, PW4168, and PW4168A turbofan engines. This AD was prompted by fuel nozzle-to-fuel supply manifold interface fuel leaks. This AD requires inspecting fuel nozzles for signs of leakage, replacing hardware as required, and torqueing to specified requirement. We are issuing this AD to prevent fuel leaks which could result in engine fire and damage to the airplane.
(1) Within 800 flight hours after the effective date of this AD, and within every 800 flight hours since last inspection thereafter, inspect all fuel nozzle-to-fuel supply manifold interfaces for evidence of fuel leaks, soot, and coke formation. Use the Accomplishment Instructions, Part A, of PW Alert Service Bulletin (ASB) No. PW4G-100-A73-44, Revision 1, dated February 12, 2015 to do the inspections.
(2) Replace hardware that fails an inspection. Use the Accomplishment Instructions, Part A, of PW ASB No. PW4G-100-A73-44, Revision 1, dated February 12, 2015 to do the replacement.
As terminating action to the repetitive inspection requirements in paragraph (e)(1) of this AD do the following:
(1) Inspect all fuel nozzle-to-fuel supply manifold interfaces for fuel leaks, soot, and coke formation, replace hardware that fails inspection, and re-torque all fuel nozzle-to-fuel supply manifold B-nuts as follows:
(i) For engines with fewer than 1,500 cycles on the effective date of this AD, before accumulating another 650 cycles, not to exceed 1,900 cycles.
(ii) For engines with 1,500 cycles or more, but less than 2,500 cycles on the effective date of this AD, before accumulating another 400 cycles, not to exceed 2,700 cycles.
(iii) For engines with 2,500 cycles or more on the effective date of this AD, before accumulating another 200 cycles.
(2) Use the Accomplishment Instructions, Parts B through E, of PW ASB No. PW4G-100-A73-44, Revision 1, dated February 12, 2015 to do the inspection, replacement, and retorqueing.
This paragraph provides credit for the actions required by paragraphs (e) and (f) of this AD, if the actions were performed before the effective date of this AD, using the procedures specified in PW ASB No. PW4G-100-A73-44, dated October 10, 2014 or Special Instruction 129F-14.
For the purpose of this AD “cycles” is defined as cycles since new or cycles since last torque application to the B-nuts on the fuel nozzle installation.
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.
