AD 99-24-07 Airworthiness Directives; Boeing Model 757 Series Airplanes Equipped With Rolls Royce Engines

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

Model 757 series airplanes equipped with Rolls Royce 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 (b) 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: (a) Modify the nacelle strut and wing structure in accordance with Boeing Service Bulletin 757-54-0035, dated July 17, 1997, at the later of the times specified in paragraph (a)(1) or (a)(2). All of the terminating actions described in the service bulletins listed in paragraph I.C., Table I, ``Strut Improvement Bulletins,'' on page 6 of Boeing Service Bulletin 757-54-0035, must be accomplished in accordance with those service bulletins prior to, or concurrently with, the accomplishment of the modification of the nacelle strut and wing structure required by this paragraph. (1) Prior to the accumulation of 37,500 total flight cycles, or prior to 20 years since the date of manufacture of the airplane, whichever occurs first. (2) Within 3,000 flight cycles after the effective date of this AD. Alternative Methods of Compliance (b) 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 Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. 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. [[Page 66372]] 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 (c) Special flight permits may be issued in accordance with Secs. 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 (d) The modification shall be done in accordance with Boeing Service Bulletin 757-54-0035, dated July 17, 1997. 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. (e) This amendment becomes effective on January 3, 2000. Issued in Renton, Washington, on November 17, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-30518 Filed 11-24-99; 8:45 am] BILLING CODE 4910-13-P