AD 2004-25-14

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas airplane models, that requires an inspection of the retract cylinder support fitting and the cylinder bore of the support fitting of both main landing gear (MLG) for corrosion, and corrective action if necessary. This action also requires replacing cadmium-plated retract cylinder support bushings and bearings of both MLG. This action is necessary to detect and correct corrosion to the retract cylinder support fitting of the MLG and the cylinder bore in the support fitting, which could result in compromised integrity of the retract cylinder support fitting of the MLG and possible damage to the hydraulic system. This action is intended to address the identified unsafe condition.

Final rule.

2004-25-14 McDonnell Douglas: Amendment 39-13902. Docket 2002-NM- 333-AD. \n\n\tApplicability: Model DC-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), and DC-9-87 (MD-87) airplanes; and Model MD-88 airplanes; as listed in Boeing Service Bulletin DC9-57-222, dated September 18, 2002; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo detect and correct corrosion to the retract cylinder support fitting of the main landing gear (MLG) and the cylinder bore in the support fitting, which could result in compromised integrity of the retract cylinder support fitting of the MLG and possible damage to the hydraulic system, accomplish the following: \n\nInspection and Replacement \n\n\t(a) Prior to the accumulation of 30,000 total flight hours, or within 15,000 flight hours after the effective date of the AD, whichever is later, do the actions in paragraphs (a)(1) and (a)(2) of this AD in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC9-57-222, dated September 18, 2002. \n\n\t(1) Do the inspection specified in paragraph (a)(1)(i) or (a)(1)(ii) of this AD, as applicable. Before further flight following the inspection, accomplish all applicable corrective actions specified in the Accomplishment Instructions of Boeing Service Bulletin DC9-57-222, dated September 18, 2002. Do the actions in accordance with the service bulletin. \n\n\t(i) For Group 1 airplanes specified in paragraph 1.A.1. of the service bulletin, do a general visual inspection of the retract cylinder support fitting and the cylinder bore of the support fitting of both MLG for corrosion. \n\n\t(ii) For Group 2 airplanes specified in paragraph 1.A.1. of the service bulletin, do a general visual inspection of the retract cylinder support fitting of both MLG for corrosion. \n\n\tNote1: For the purposes of this AD, a general visual inspection is defined as: "A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked." \n\n\t(2) Replace cadmium-plated retract cylinder support bushings and bearings of the MLG with bushings and bearings that do not have cadmium plating in the bore. \n\nParts Installation \n\n\t(b) As of the effective date of this AD, no person shall install a retract cylinder support fitting for the MLG, partnumber (P/N) 3935860-1, 3912891-1, or 3912891-501 on any airplane, unless it has been found to have no corrosion during the inspection required by paragraph (a) of this AD, or unless it has been modified in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC9-57-222, dated September 18, 2002. \n\nAlternative Methods of Compliance \n\n\t(c) 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(d) The actions shall be done in accordance with Boeing Service Bulletin DC9-57-222, dated September 18, 2002. 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 National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html . \n\nEffective Date \n\n\t(e) This amendment becomes effective on January 20, 2005.

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 May 11, 2004 (69 FR 26052). That action proposed to require an inspection of the retract cylinder support fitting and the cylinder bore of the support fitting of both main landing gear (MLG) for corrosion, and corrective action if necessary. That action also proposed to require replacing cadmium- plated retract cylinder support bushings and bearings of both MLG. \n\nComments \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\nClarification of the Cost Estimate \n\n\tOne commenter estimates it will cost more than $30,000 per airplane for its fleet of 362 airplanes to accomplish the inspection and replacement; for atotal cost of over $11,000,000. \n\n\tWe infer that the commenter wants further clarification of the cost estimate specified in the proposed AD. The estimate for both the inspection and replacement in the Cost Impact section of the final rule is between $20,617 and $29,861 per airplane, which is lower than the commenter's cost estimate of more than $30,000 per airplane. However, the cost estimate in the proposed AD describes only the direct costs of those specific actions required by the proposed AD. We recognize that, in doing the actions required by an AD, operators may incur incidental costs in addition to the direct costs. As explained in the proposed AD, the cost analysis in AD rulemaking actions typically does not include incidental costs such as the time required to gain access and close up, time necessary for planning, or time necessitated by other administrative actions. Those incidental costs, which may vary significantly among operators, are almost impossible to calculate. Therefore, we have not changed the cost estimate in this final rule. \n\nConclusion \n\n\tAfter careful review of the available data, including the comment noted above, we have determined that air safety and the public interest require the adoption of the rule as proposed. \n\nClarification of Service Information Reference \n\n\tWhere paragraph (b) of the proposed AD specifies, "in accordance with the service bulletin," this final rule specifies, "in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC9-57- 222, dated September 18, 2002." \n\nCost Impact \n\n\tThere are approximately 1,904 airplanes of the affected design in the worldwide fleet. We estimate that 1,188 airplanes of U.S. registry will be affected by this AD. \n\n\tWe estimate that it will take approximately 1 work hour per airplane to accomplish the required inspection on both MLG, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the required inspection on U.S. operators is estimated to be $77,220, or $65 per airplane. \n\n\tWe estimate that it will take approximately between 28 and 42 work hours per airplane to accomplish the required replacement on both MLG, and that the average labor rate is $65 per work hour. Required parts will cost between approximately $18,732 per airplane and $27,066 per airplane. Based on these figures, the cost impact of the required replacement on U.S. operators is estimated to be between $24,415,776 and $35,397,648, or between $20,552 and $29,796 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. 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\nAuthority for This Rulemaking \n\n\tThe FAA's authority to issue rules regarding aviation safety is found in Title 49 of the United States Code. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority. \n\n\tThis rulemaking is promulgated under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements." Under that section, the FAA is charged with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this AD. \n\nRegulatory ImpactThe 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\nAccordingly, 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\n1. 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\n2. Section 39.13 is amended by adding the following new airworthiness directive: