AD 96-11-03

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747-200, -300, and -400 series airplanes, that currently requires inspection of each fuel feed line of the outboard engine in the engine strut to determine if interference with an adjacent pneumatic duct clamp has caused damage, and repair or replacement of the fuel feed tube, if necessary. That AD also currently requires inspection and replacement of the adjacent pneumatic duct clamp with a non-rotating type clamp, if necessary. This amendment requires modification of the upper gap area of the strut of the number 1 and 4 engines. This amendment is prompted by a report of fuel leakage in the strut of the number 4 engine due to a high profile clamp that chafed the fuel line. The actions specified by this AD are intended to prevent chafing of the fuel line in the strut of the number 1 and 4 engines, which could result in rupture of the fuel line and subsequent in-flightengine fire.

Final rule

96-11-03 BOEING: Amendment 39-9628. Docket 95-NM-162-AD. Supersedes AD 91-05-19, Amendment 39-6918. \n\n\tApplicability: Model 747-200, -300, and -400 series airplanes having line positions 679 through 1041 inclusive; equipped with General Electric Model CF6-80C2 PMC and CF6-80C2 FADEC, and Pratt & Whitney Model PW4000 engines; certificated in any category.\n \n\tNOTE 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. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent chafing of the fuel line in the strut of the number 1 and 4 engines, which could result in rupture of the fuel line and subsequent in-flight engine fire, accomplish the following: \n\n\t(a)\tWithin 6 months after the effective date of this AD, modify the upper gap area of the strut of the number 1 and 4 engines, in accordance with Boeing Service Bulletin 747-36A2097, Revision 3, dated September 28, 1995. \n\n\t(b)\tAn 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. \n\n\tNOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\n\t(c)\tSpecial 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. \n\n\t(d)\tThe modification shall be done in accordance with Boeing Service Bulletin 747-36A2097, Revision 3, dated September 28, 1995. 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. \n\n\t(e)\tThis amendment becomes effective on June 26, 1996.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 91-05-19, amendment 39-6918 (56 FR 8705, March 1, 1991), which is applicable to certain Boeing Model 747-200, -300, and -400 series airplanes, was published in the Federal Register on January 29, 1996 (61 FR 2730). The action proposed to supersede AD 91-05-19 to require modification of the upper gap area of the strut of the number 1 and 4 engines. \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the two comments received. \n\n\tBoth commenters support the proposed rule.\n\n Conclusion \n\n\tAfter careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. \n\nCost Impact \n\n\tThere are approximately 363 Boeing Model 747-200, -300, -400 series airplanes equipped with General Electric Model CF6-80C2 PMC and CF6-80C2 FADEC engines, and Pratt & Whitney Model PW4000 engines of the affected design in the worldwide fleet. The FAA estimates that 39 airplanes of U.S. registry will be affected by this AD. \n\n\tThe actions that are required by this AD will take approximately 6 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will be supplied by the manufacturer at no cost to the operators. Based on these figures, the cost impact on U.S. operators of the new requirements of this AD is estimated to be $14,040, or $360 per airplane. \n\n\tThe cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. \n\nRegulatory Impact \n\n\tThe regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.\n \n\tFor the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."\n \nList of Subjectsin 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\n\tAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:\n\nPART 39 - AIRWORTHINESS DIRECTIVES \n\n\t1.\tThe authority citation for part 39 continues to read as follows: Authority: 49 USC 106(g), 40113, 44701. § 39.13 - (Amended) \n\n\t2.\tSection 39.13 is amended by removing amendment 39-6918 (56 FR 8705, March 1, 1991), and by adding a new airworthiness directive (AD), amendment 39-9628, to read as follows: