AD 2000-20-09 Airworthiness Directives; Boeing Model 757 Series Airplanes Powered by Pratt & Whitney Engines

Models named: 757 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 757 series airplanes powered by Pratt & Whitney engines, line numbers 1 through 735 inclusive, certificated in any category. Note 1: This AD applies to each airplane 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 airplanes 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 (d) 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 fatigue cracking in primary strut structure and consequent reduced structural integrity of the strut, accomplish the following: Modifications (a) Modify the nacelle strut and wing structure on both the left and right sides of the airplane, in accordance with Boeing Service Bulletin 757-54-0034, dated May 14, 1998, at the later of the times specified in paragraph (a)(1) or (a)(2) of this AD. (1) Prior to the accumulation of 37,500 total flight cycles, or within 20 years since the date of manufacture, whichever occurs first. Use of the optional threshold formula described in paragraph I.D. of the service bulletin is an acceptable alternative to the 20-year threshold. (2) Within 3,000 flight cycles after the effective date of this AD. (b) Prior to or concurrently with the accomplishment of the modification of the nacelle strut and wing structure required by paragraph (a) of this AD; as specified in paragraph I.D., Table I, “Strut Improvement Bulletins,” on page 5 of Boeing Service Bulletin 757-54-0034, dated May 14, 1998; accomplish the actions specified in Boeing Service Bulletin 757-54-0027, Revision 1, dated October 27, 1994, and Boeing Service Bulletin 757-54-0036, dated May 14, 1998, as applicable, in accordance with those service bulletins. Repair (c) If any damage to airplane structure is found during the accomplishment of the modification required by paragraph (a) of this AD; and the service bulletin specifies to contact Boeing for appropriate action: Prior to further flight, repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative (DER) who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved by the Manager, Seattle ACO, as required by this paragraph, the approval letter must specifically reference this AD. Alternative Methods of Compliance (d) 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, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (e) Special flight permits may be issued in accordance with §§ 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 (f) Except as provided by paragraph (c) of this AD, the actions shall be done in accordance with Boeing Service Bulletin 757-54-0034, dated May 14, 1998; Boeing Service Bulletin 757-54-0027, Revision 1, dated October 27, 1994; and Boeing Service Bulletin 757-54-0036, dated May 14, 1998; as applicable. 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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date (g) This amendment becomes effective on November 13, 2000. Issued in Renton, Washington, on September 28, 2000. Donald L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 00-25433 Filed 10-5-00; 8:45 am] BILLING CODE 4910-13-U