2006-22-13: Anti-rotation slots

2006-22-13 Pratt & Whitney: Amendment 39-14810. Docket No. FAA-2006- 24487; Directorate Identifier 2006-NE-13-AD. Effective Date (a) This airworthiness directive (AD) becomes effective December 7, 2006. Affected ADs (b) None. Applicability (c) This AD applies to Pratt & Whitney PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, PW4090-3, and PW4098 turbofan engines, with front turbine hub part numbers 50L761, 52L701, 55L221, 52L901, 53L121, 55L521, and 53L021, installed. These engines are installed on, but not limited to, Boeing 777 airplanes. Unsafe Condition (d) This AD results from a report of a crack found in an anti- rotation slot of a front turbine hub, during overhaul shop inspection. The anti-rotation slot geometry was not machined in conformance with the design drawing during manufacture. We are issuing this AD to prevent uncontained engine failure, damage to the airplane, and injury to passengers. Compliance (e) You are responsible for having the actions required by this AD performed at the next disassembly at piece-part level of the front turbine hub after the effective date of this AD, unless the actions have already been done. Onetime Visual Inspection (f) For front turbine hubs listed by part number and serial number in Table 1, Table 2, and Table 3 of Pratt & Whitney Service Bulletin (SB) No. PW4G-112-72-282, Revision 1, dated March 3, 2006, do the following: (1) Perform a onetime visual inspection for extra fillet radii in the anti-rotation slots. (2) Use paragraphs 1.A. through 1.C.(2) of the Accomplishment Instructions of Pratt & Whitney SB No. PW4G-112-72-282, Revision 1, dated March 3, 2006, to do the inspection. (3) Remove from service any front turbine hub that has extra fillet radii in the anti-rotation slots and install a serviceable front turbine hub. Prohibition of Front Turbine Hubs That Have Extra Fillet Radii in the Anti-Rotation Slots (g) After the effectivedate of this AD, do not install any front turbine hub that has extra fillet radii in the anti-rotation slots, onto any engine. Previous Credit (h) Previous credit is allowed for front turbine hubs inspected using Pratt & Whitney SB No. PW4G-112-72-282, dated February 27, 2006, or Revision 1, dated March 3, 2006, before the effective date of this AD. Alternative Methods of Compliance (i) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19. Material Incorporated by Reference (j) You must use Pratt & Whitney Service Bulletin No. PW4G-112- 72-282, Revision 1, dated March 3, 2006, to perform the actions required by this AD. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860) 565- 8770; fax (860) 565-4503, for a copy of this service information. You may review copies at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202- 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html .