AD 2000-16-02 Airworthiness Directives; Pratt & Whitney PW4164, PW4168, and PW4168A Series Turbofan Engines

Pratt & Whitney (PW) PW4164, PW4168, and PW4168A series turbofan engines, with front pylon mount bolts, part numbers (P/Ns) 54T670 or 51U615, installed. These engines are installed on but not limited to Airbus Industrie A330 series airplances. Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To prevent front pylon mount bolt and primary mount thrust load path failure, which could result in engine separation from the airplance, accomplish the following: INCO 718 Material Bolts Torque Checks (a) Perform initial and repetitive torque checks of INCO 718 material front pylon mount bolts, P/N 54T670, and replace, if necessary, with new bolts, in accordance with the Accomplishment Instructions of Pratt & Whitney (PW) Alert Service Bulletin (ASB) No. PW4G-100-A71-9, Revision 1, dated November 24, 1997, as follows: (1) For front pylon mount bolts, P/N 54T670, with fewer than 1,000 cycles-in-service-since-new (CSN) on the effective date of this AD, accomplish the following in accordance with Part (A) of the Accomplishment Instructions of the SB: (i) Perform an initial torque check prior to accumulating 1,250 CSN or at the next engine removal for cause, whichever occurs first. (ii) Thereafter, perform torque checks at intervals not fewer than 750 or greater than 1,250 cycles in service (CIS) since last torque check, not to exceed 11,000 CSN. (2) For front pylon mount bolts, P/N 54T670, with 1,000 or more CSN but fewer than 5,750 CSN on the effective date of this AD, accomplish the following in accordance with Part (A) of the Accomplishment Instructions of the SB: (i) Perform an initial torque check within 250 CIS after the effective date of this AD, or at the next engine removal for any cause, whichever occurs first. (ii) Thereafter, perform torque checks at intervals not fewer than 750 or greater than 1,250 CIS since last torque check, not to exceed 11,000 CSN. (3) For front pylon mount bolts, P/N 54T670, with 5,750 or more CSN on the effective date of this AD, accomplish the following in accordance with Part (B) of the Accomplishment Instructions of the SB: (i) Perform an initial torque check within 250 CIS after the effective date of this AD, or prior to the next engine removal for any cause, whichever occurs first. (ii) Thereafter, perform torque checks at intervals not fewer than 750 or greater than 1,250 CIS since last torque check, not to exceed 11,000 CSN. (4) Prior to further flight, replace all four bolts in accordance with Part (A), Paragraph 1(D) of the Accomplishment Instructions of the SB, if any of the bolts are loose or broken. INCO 718 Material Bolts Life Limit (b) This AD establishes a new life limit of 11,000 CSN for front pylon mount bolts, P/N 54T670. Except as provided in paragraph (e) of this AD, no front pylon mount bolts, P/N 54T670, may exceed this new life limit after the effective date of this AD. MP159 Material Bolts Inspections (c) Perform initial and repetitive torque inspections of front pylon mount bolts, P/N 51U615, in accordance with the Accomplishment Instructions of PW ASB PW4G-100-A71-20, dated December 9, 1999, as follows: (1) For front pylon mount bolts with fewer than 1,000 CSN on the effective date of this AD, perform the initial torque inspection at the earlier of the following: (i) Before accumulating 1,250 CSN, or (ii) The next engine removal for any cause. (2) For front pylon mount bolts with 1,000 or more CSN on the effective date of this AD, perform the initial torque check at the earlier of the following: (i) Within 250 CIS after the effective date of this AD, or (ii) The next engine removal for any cause. (3) Thereafter, perform torque inspections at intervals not fewer than 750 or greater than 1,250 CIS since last torque inspection. (4) Prior to further flight, replace all four bolts, in accordance with Paragraph 1(D) of the Accomplishment Instructions of the ASB, if any are loose or broken. Primary Mount Thrust Load Path Inspections (d) Perform initial and repetitive visual inspections of the primary mount thrust load path, in accordance with the Accomplishment Instructions of PW ASB PW4G-100-A71-18, Revision 1, dated December 9, 1999, as follows: (1) For forward engine mount assemblies with fewer than 1,000 CSN on the effective date of this AD, perform the initial visual inspection at the earlier of the following: (i) Before accumulating 1,250 CSN, or (ii) The next engine removal for any cause. (2) For forward engine mount assemblies with 1,000 or more CSN on the effective date of this AD, perform the initial visual inspection at the earlier of the following: (i) Within 250 CIS after the effective date of this AD, or (ii) The next engine removal for any cause. (3) Thereafter, perform visual inspections at intervals not fewer than 750 or greater than 1,250 CIS since last visual inspection. (4) Prior to further flight, replace all cracked parts with serviceable parts and inspect the primary thrust load path components in accordance with Paragraph 4 of the accomplishment instructions of the SB. Alternative Method of Compliance (e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office (ECO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO. Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the ECO. Special Flight Permits (f) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (g) The inspection shall be done in accordance with the following PW ASBs: * Document No. Pages Revision Date PW4G-100-A71-9 11 Rev. 1 November 24, 1997 PW4G-100-A71-20 10 December 9, 1999 PW4G-100-A71-18 12 Rev. 1 December 9, 1999 This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860) 565-8860, fax (860) 565-4503. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date This amendment becomes effective on October 16, 2000. Issued in Burlington, Massachusetts, on August 1, 2000. David A. Downey, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 00-20241 Filed 8-14-00; 8:45 am] BILLING CODE 4910-13-U