Airworthiness Directive · Amendment 39-16924 · Pratt & Whitney (PW) Turbofan Engines
Pratt & Whitney (PW) Turbofan Engines
This AD applies to Pratt & Whitney (PW) PW2037, PW2037(M), and PW2040 turbofan engines with six or more fan blades, part numbers (P/Ns) 1B6531, 1B6231-001, or 1A9031-001 (fan blade set P/Ns 1B6521, 1B6221-001, and 1A9721-001), with a cutback leading edge, installed.
We are adopting a new airworthiness directive (AD) for Pratt & Whitney (PW) PW2037, PW2037(M), and PW2040 turbofan engines with certain fan blades with a cutback leading edge, installed. This AD was prompted by reports from PW that fan blade leading edge erosion can result in a fan thrust deterioration mode (FTDM) condition, a condition that cannot be detected by the crew, and that reduces the engine's capability of producing required thrust. This AD requires initial and repetitive maintenance to the leading edge of cutback fan blades or applying performance decrements as specified in the Airplane Flight Manual. We are issuing this AD to correct undetectable fan thrust deterioration on these PW products.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
(1) Within 500 cycles-in-service (CIS) after the effective date of this AD or within 1,000 CIS after the last leading edge restoration, whichever occurs later, do one of the following. Whichever method you choose, you must implement the method in full.
(i) For engines installed on the airplane, perform the initial restoration using Accomplishment Instructions For Engines Installed on Aircraft, paragraphs 1. through 1.T. of PW Alert Service Bulletin (ASB) PW2000 A72-729, Revision 2, dated October 13, 2010.
(ii) For engines that are not installed on the airplane, perform the initial restoration using Accomplishment Instructions For Engines Not Installed on Aircraft, paragraphs 1. through 1.S. of PW ASB PW2000 A72-729, Revision 2, dated October 13, 2010.
(iii) Perform Repair-14, dated February 1, 2006, from a Pratt & Whitney PW2037, PW2040, PW2240, PW2337 Turbofan Engine Manual, Part No. 1A6231, Chapter/Section 72-31-12.
(iv) Perform Repair-18, dated February 1, 2004, from a Pratt & Whitney PW2037, PW2040, PW2240, PW2337 Turbofan Engine Manual, Part No. 1A6231, Chapter/Section 72-31-12.
(v) Perform PW Service Bulletin PW2000 72-513, Revision 4, dated August 20, 1997.
(vi) Revise the Limitations Section of the Boeing 757 Airplane Flight Manual (AFM), Document D631N002, to include the following limitation. This may be done by inserting a copy of this AD into the AFM.
(vii) Revise the Limitations Section of the Boeing 757 Airplane Flight Manual, Document D631N007, to include the following limitation. This may be done by inserting a copy of this AD into the AFM.
(2) If you chose one of the methods in paragraphs (f)(1)(i) through (f)(1)(v) of this AD, thereafter, within 1,000 CIS, repeat one of the methods in paragraphs (f)(1)(i) through (f)(1)(v) of this AD. Whichever method you choose, you must implement the method in full.
(3) If you chose one of the methods in paragraphs (f)(1)(vi) or (f)(1)(vii) of this AD, you have fully complied with the requirements of this AD and no further action is required. When a statement identical to that in paragraph (f)(1)(vi) or (f)(1)(vii) of this AD has been included in the Limitations Section of the general revisions of the AFM, the general revisions may be inserted into the AFM, and the copy of this AD may be removed from the AFM.
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.
