AD 2004-05-25

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas airplane models, that requires inspection of the captain's and first officer's seat locking pins for minimum engagement with the detent holes in the seat tracks; inspection of the seat lockpins for excessive wear; and corrective actions, if necessary. This action is necessary to prevent uncommanded seat movement during takeoff and/or landing, which could result in interference with the operation of the airplane and consequent temporary loss of control of the airplane. This action is intended to address the identified unsafe condition.

Final rule.

2004-05-25 McDonnell Douglas: Amendment 39-13520. Docket FAA-2003-16647, Directorate Docket No. 2002-NM-203-AD. \n\n\tApplicability: This AD applies to the airplanes listed in Table 1 of this AD, certificated in any category: \n\nTable 1.-Applicability\n\n\nMcDonnell Douglas model\nAs listed in\nDC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, DC-9-51, DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes.\nBoeing Alert Service Bulletin DC9-25A350, Revision 01, dated June 14, 2002.\nMD-90-30 airplanes\nBoeing Alert Service Bulletin MD90-25A009, Revision 01, dated July 1, 2002.\n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent uncommanded seat movement during takeoff and/or landing, which could result in interference with the operation of the airplane and consequent temporary loss of control of the airplane, accomplish thefollowing: \n\nService Bulletin References \n\n\t(a) The term "service bulletin," as used in this AD, means the Accomplishment Instructions of the applicable service bulletins listed in Table 1 of this AD. \n\nInspection for Engagement and Excessive Wear of the Seat Locking Pins \n\n\t(b) Within 18 months after the effective date of this AD, do the actions specified in paragraphs (b)(1) and (b)(2) of this AD, per the service bulletin. \n\n\t(1) Do a detailed inspection of the seat locking pin for minimum engagement with the detent holes in the seat track of the captain's and first officer's seat assemblies. \n\n\tNote 1: For the purposes of this AD, a detailed inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required." \n\n\t(2) Do a detailed inspection of the seat lock pins for excessive wear. \n\nCorrective Actions \n\n\t(c) If any discrepancy is detected during the inspections required by paragraph (b) of this AD, before further flight, do the corrective action(s), as applicable, per the service bulletin. Those corrective actions include adjusting/replacing the seat locking pin with a new pin and/or adjusting/repairing/replacing the seat track with a new track. \n\nAlternative Methods of Compliance \n\n\t(d) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance for this AD. \n\nIncorporation by Reference \n\n\t(e) The actions shall be done in accordance with Boeing Alert Service Bulletin DC9-25A350, Revision 01, dated June 14, 2002; or Boeing Alert Service Bulletin MD90-25A009, Revision 01, dated July 1,2002; 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 Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\nEffective Date \n\n\t(f) This amendment becomes effective on April 19, 2004.

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 McDonnell Douglas airplane models was published in the Federal Register on December 11, 2003 (68 FR 69501). That action proposed to require inspection of the captain's and first officer's seat locking pins for minimum engagement with the detent holes in the seat tracks; inspection of the seat lockpins for excessive wear; and corrective actions, if necessary. \n\nComments \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public. \n\nConclusion \n\n\tThe 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 2,166 airplanes of the affected design in the worldwidefleet. The FAA estimates that 1,355 airplanes of U.S. registry will be affected by this AD. It will take approximately between 1 and 3 work hours per seat (depending on airplane configuration) to accomplish the required inspection. Each airplane has 2 seats (the captain and first officer seats); therefore, it will take approximately between 2 and 6 work hours per airplane (depending on airplane configuration) to accomplish the required inspection, at the average labor rate of $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be between $176,150 and $528,450, or between $130 and $390 per airplane, depending on airplane configuration. \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. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions. \n\nRegulatory Impact \n\n\tThe regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132. \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 the Federal 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: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: