AD 2000-26-04 Airworthiness Directives; Boeing Model 747, 757, 767 and 777 Series Airplanes

Models named: 747, 757, 767, 777 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 747, 757, 767, and 777 series airplanes having the line numbers listed below; certificated in any category.   Model Affected line numbers (L/N) Except L/N 747 1 through 1234 inclusive 1174, 1216 757 2 through 895 inclusive 870, 886, 894 767 1 through 768 inclusive 758 777 2 through 254 inclusive 120, 219, 230, 235, 242, 245, 249 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 potential ignition of the moisture barrier cover of the drip shield, which could propagate a small fire that results from an otherwise harmless electrical arc, leading to a larger fire, accomplish the following: Modification (a) Within 6 years after the effective date of this AD, accomplish paragraphs (a)(1), (a)(2), and (a)(3) of this AD; in accordance with Boeing Service Bulletin 747-25-3253, 767-25-0290, or 777-25-0164; all including Appendices A, B, and C; all dated June 29, 2000; or 757-25-0226 or 757-25-0228; both including Appendices A, B, and C; both dated July 3, 2000; as applicable; except as provided by paragraph (b) of this AD. (1) Modify drip shields located on the flight deck by installing fire blocks. (2) Prior to further flight following accomplishment of paragraph (a)(1) of this AD, perform a functional test of any system disturbed by the modification, in accordance with the applicable service bulletin or the Airplane Maintenance Manual (AMM), as applicable. If any functional test fails, prior to further flight, isolate the fault, correct the discrepancy in accordance with the applicable AMM, and repeat the failed test until it is successfully accomplished. (3) Prior to further flight following the accomplishment of paragraphs (a)(1) and (a)(2) of this AD, install placards on all modified drip shields. (b) If any wires or equipment are installed on the outboard surface of the drip shield (that is, between the drip shield and the airplane structure), modify that area in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. Optional Sampling (Certain Model 747 and 767 Series Airplanes) (c) For Model 747 and 767 series airplanes listed in Group 1 in Boeing Service Bulletins 747-25-3253 and 767-25-0290: In lieu of accomplishment of paragraph (a) of this AD, within 6 years after the effective date of this AD, collect samples of the insulation and adhesive of the drip shields, and submit the samples to the manufacturer for testing, in accordance with Boeing Service Bulletin 747-25-3253 or 767-25-0290; both including Appendices A, B, and C; both dated June 29, 2000; as applicable. (1) If the test on all samples is positive, no further action is required by this AD. (2) If the test on any sample is negative, accomplish paragraph (a) of this AD before the compliance time specified in that paragraph. 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 (b) of this AD, the actions shall be done in accordance with Boeing Service Bulletin 747-25-3253, including Appendices A, B, and C, dated June 29, 2000; Boeing Service Bulletin 767-25-0290, including Appendices A, B, and C, dated June 29, 2000; Boeing Service Bulletin 777-25-0164, including Appendices A, B, and C, dated June 29, 2000; Boeing Service Bulletin 757-25-0226, including Appendices A, B, and C, dated July 3, 2000; or Boeing Service Bulletin 757-25-0228, including Appendices A, B, and C, dated July 3, 2000; 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 February 2, 2001. Issued in Renton, Washington, on December 20, 2000. John J. Hickey, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 00-33017 Filed 12-28-00; 8:45 am] BILLING CODE 4910-13-P