AD 2010-16-11

We are adopting a new airworthiness directive (AD) for certain Model MD-90-30 airplanes. This AD requires inspecting for corrosion of the retract cylinder support fitting for the main landing gear (MLG) and the mating bore for the support fitting in the MLG trunnion fitting, performing corrective actions if necessary, and replacing cadmium-plated retract cylinder support bushings and bearings. This AD results from reports of the retract cylinder support fitting for the MLG failing during gear extension and subsequently damaging the hydraulic system. We are issuing this AD to prevent corrosion and damage that could compromise the integrity of the retract cylinder support fitting for the MLG, which could adversely affect the airplane's safe landing.

Final rule.

2010-16-11 McDonnell Douglas Corporation: Amendment 39-16388. Docket No. FAA-2010-0433; Directorate Identifier 2009-NM-117-AD. \n\nEffective Date \n\n\t(a) This airworthiness directive (AD) is effective September 22, 2010. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to McDonnell Douglas Corporation Model MD- 90-30 airplanes, certificated in any category, as identified in Boeing Service Bulletin MD90-57-016, Revision 2, dated April 28, 2006. \n\nSubject \n\n\t(d) Air Transport Association (ATA) of America Code 57: Wings. \n\nUnsafe Condition \n\n\t(e) This AD results from reports of the retract cylinder support fitting for the main landing gear (MLG) failing during gear extension, and subsequently damaging the hydraulic system. The Federal Aviation Administration is issuing this AD to prevent corrosion and damage that could compromise the integrity of the retract cylinder support fitting for the MLG, which could adversely affect the airplane's safe landing.Compliance \n\n\t(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. \n\nInspection and Corrective Actions \n\n\t(g) Before the accumulation of 30,000 total flight hours, or within 15,000 flight hours after the effective date of this AD, whichever occurs later, do a general visual inspection of the retract cylinder support fitting for the MLG and the mating bore in the MLG trunnion fitting for corrosion, install bushings and bearings without cadmium plating in the bore, and do all applicable corrective actions, in accordance with Configuration 1 of the Accomplishment Instructions of Boeing Service Bulletin MD90-57-016, Revision 2, dated April 28, 2006. Do all applicable corrective actions before further flight. \n\n\tNote 1: For the purposes of this AD, a general visual inspection is: "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 ensure visual access to all 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(h) Doing a general visual inspection, installing bushings and bearings, and doing all applicable corrective actions is also acceptable for compliance with the requirements of paragraph (g) of this AD if done before the effective date of this AD in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD90-57-016, Revision 1, dated October 26, 2005. \n\t(i) Doing a general visual inspection, installing bushings and bearings, and doing all applicable corrective actions is also acceptable for compliance with the requirements of paragraph (g) of this AD if done before the effective date of this AD in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD90-57-016, dated September 18, 2002, provided that before the accumulation of 30,000 total flight hours, or within 15,000 flight hours after the effective date of this AD, whichever occurs later, electroless nickel fittings are installed, and bushings and bearings without cadmium plating in the bore are installed in accordance with the Accomplishment Instructions of any of the service bulletins listed in Table 1 of this AD. \n\n\tTable 1--Service Information\n\n\nDocument \nRevision \nDate \nIncorporated by reference \nBoeing Service Bulletin MD90-57-016 \n1 \nOctober 26, 2005 \nNo\nBoeing Service Bulletin MD90-57-016 \n2 \nApril 28, 2006 \nYes\n\nAlternative Methods of Compliance (AMOCs) \n\n\t(j)(1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Roger Durbin, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5233; fax (562) 627-5210. \n\t(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD. \n\t(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by Boeing Commercial Airplanes Organization Designation Authorization (ODA) who has been authorized by the Manager, Los Angeles ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and 14 CFR 25.571, Amendment 45, and the approval must specifically refer to this AD. \n\nMaterial Incorporated by Reference \n\n\t(k) You must use Boeing Service Bulletin MD90-57-016, Revision 2, dated April 28, 2006, to do the actions required by this AD, unless the AD specifies otherwise. \n\t(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. \n\t(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846- 0001; telephone 206-544-5000, extension 2; fax 206-766-5683; e-mail dse.boecom@boeing.com; Internet https://www.myboeingfleet.com. \n\t(3) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221. \n\t(4) You may also review copies of the service information that is incorporated by reference 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.

Discussion \n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Model MD-90-30 airplanes. That NPRM was published in the Federal Register on April 26, 2010 (75 FR 21528). That NPRM proposed to require inspecting for corrosion of the retract cylinder support fitting for the main landing gear (MLG) and the mating bore for the support fitting in the MLG trunnion fitting, performing corrective actions if necessary, and replacing cadmium-plated retract cylinder support bushings and bearings. \n\nComments \n\n\tWe gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public. \n\nConclusion \n\n\tWe reviewed the relevant data and determined that air safety and the public interest require adopting the AD as proposed. \n\nCosts of Compliance \n\n\tWe estimate that this AD affects16 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this AD. \n\n\tTable--Estimated Costs\n\n\nAction\nWork hours\nAverage labor rate per hour\nParts\nCost per product\nNumber of U.S.-registered airplanes\nFleet cost\nInspection\n1\n$85\n$0\n$85\n16\n$1,360\nReplacement\n8\n$85\n$24,580\n$25,260\n16\n$404,160\n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. 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\tWe are issuing this rulemaking under the authority described in "Subtitle VII, Part A, Subpart III, Section 44701: General requirements.'' Under that section, Congress charges the FAA 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 rulemaking action. \n\nRegulatory Findings \n\n\tThis AD will not have federalism implications under Executive Order 13132. This AD 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. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a "significant regulatory action'' under Executive Order 12866, \n\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), and \n\t(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.You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket. \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, under the authority delegated to me by the Administrator, the FAA amends 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\nSec. 39.13 (Amended) \n\n2. The FAA amends Sec. 39.13 by adding the following new AD: