AD 97-16-03

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 767 series airplanes, that requires a one-time inspection of the main landing gear (MLG) retaining bolt to ensure that it is installed correctly, and adjustments or repairs, if necessary. This amendment is prompted by a report indicating that a disconnected retaining bolt was found in the MLG forward trunnion joint of a Model 767 series airplane. The actions specified by this AD are intended to prevent aft-acting trunnion loads from being transferred to the MLG beam, and consequent fracture and collapse of the MLG; this condition could result in the loss of control of the airplane on the ground.

Final rule.

97-16-03 BOEING: Amendment 39-10093. Docket 97-NM-25-AD.\n\n\tApplicability: Model 767 series airplanes, line positions 1 through 600 inclusive, except line positions 579 and 586; 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 otherwise 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 aft-acting landing gear trunnion loads from being transferred to the main landing gear (MLG) beam, and consequent fracture and collapse of the MLG and loss of control of the airplane on the ground, accomplish the following:\n\n\t(a)\tWithin 500 flight hours or 300 flight cycles after the effective date of this AD, whichever occurs later, perform a one-time inspection of the MLG retaining bolt to ensure that it is installed correctly, in accordance with Boeing Alert Service Bulletin 767-32A0157, dated October 10, 1996. If the retaining bolt is incorrectly installed, prior to further flight, make adjustments or repairs in accordance with the alert service bulletin.\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 actions shall be done in accordance with Boeing Alert Service Bulletin 767-32A0157, dated October 10, 1996. 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 September 5, 1997.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Boeing Model 767 series airplanes was published in the Federal Register on April 1, 1997 (62 FR 15435). That action proposed to require a one-time inspection of the main landing gear (MLG) retaining bolt to ensure that it is installed correctly, and adjustments or repairs, if necessary.\n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received.\n\n\tThe commenter supports the proposed rule.\n\nConclusion\n\n\tAfter careful review of the available data, including the comment 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 598 Boeing Model 767 series airplanes of the affected design inthe worldwide fleet. The FAA estimates that 151 airplanes of U.S. registry will be affected by this AD, that it will take approximately 5 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $45,300, or $300 per airplane.\n\n\tThe cost impact figure discussed above is 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 Subjects in 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 theFederal Aviation Regulations (14 CFR part 39) as follows:\n\nPART 39 - AIRWORTHINESS DIRECTIVES\n\n\t1. The authority citation for part 39 continues to read as follows:\nAuthority: 49 U.S.C. 106(g), 40113, 44701.\n§ 39.13 - (Amended)\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: