AD 2002-26-20

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), and DC-9-83 (MD-83) airplanes, and Model MD-88 airplanes, that requires an inspection of the disconnect panel area above the aft left lavatory for chafed or damaged wires or unacceptable clearance between the wires and adjacent structure, and corrective actions, if necessary. The actions specified by this AD are intended to prevent chafing of wires at the disconnect panel above the aft left lavatory, which could result in electrical arcing, and consequent fire in the cabin. This action is intended to address the identified unsafe condition.

Final rule.

2002-26-20 McDonnell Douglas: Amendment 39-13009. Docket 2000-NM- 166-AD. \n\n\tApplicability: Model DC-9-81 (MD-81), DC-9-82 (MD-82), and DC-9- 83 (MD-83) airplanes, and Model MD-88 airplanes; certificated in any category; as listed in Boeing Alert Service Bulletin MD80-24A184, dated October 26, 2000; equipped with Jamco lavatories. \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 wires at the disconnect panel above the aft left lavatory, which could result in electrical arcing, and consequent fire in the cabin, accomplish the following: \n\nInspection and Corrective Actions \n\n\t(a) Within 120 days from the effective date of this AD, perform a general visual inspection of the disconnect panel area above the aft left lavatory for damaged or chafed wires or unacceptable clearance between the wires and structure, in accordance with Boeing Alert Service Bulletin MD80-24A184, excluding Appendix and Evaluation Form, all dated October 26, 2000. \n\n\tNote 2: 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(1) Condition 1. If no damaged or chafed wire and if acceptable clearance (i.e., 0.50-inch minimum) between the wires and adjacent structure is found, no further action is required by this AD. \n\n\t(2) Condition 2. If no chafed or damaged wire and if unacceptable clearance between the wires and adjacent structure is found, before further flight, secure wires using tie-wraps to obtain a 0.50-inch minimum clearance, in accordance with the service bulletin. \n\n\t(3) Condition 3. If any chafed or damaged wire and unacceptable clearance between the wires and adjacent structure is found, before further flight, repair or replace any chafed or damaged wire with a new wire and secure wires using tie-wraps to obtain a 0.50-inch minimum clearance, in accordance with the service bulletin. \n\nAlternative Methods of Compliance \n\n\t(b) An 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, Los Angeles Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. \n\n\tNote 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\nSpecial Flight Permits \n\n\t(c) Special 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\nIncorporation by Reference \n\n\t(d) The actions shall be done in accordance with Boeing Alert Service Bulletin MD80-24A184, excluding Appendix and Evaluation Form, all dated October 26, 2000. 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 Aircraft Group, 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(e) This amendment becomes effective on February 18, 2003.

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 Model DC-9-81, -82, and -83 series airplanes, and Model MD-88 airplanes was published in the Federal Register on March 14, 2002 (67 FR 11453). That action proposed to require an inspection of the disconnect panel area above the aft left lavatory for chafed or damaged wires or unacceptable clearance between the wires and adjacent structure, and corrective actions, if necessary. \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 comments received. \n\nRequest To Withdraw Proposed AD \n\n\tOne commenter suggests that the FAA reconsider mandating the service bulletin referenced in the proposed AD until other methods of resolution are investigated. Specifically, the commenter would like theFAA to work with Jamco and Boeing to develop a better solution, such as modifying the connector bracket and protecting the adjacent wire bundle. The commenter states that its airplanes have had wire chafing in the disconnect panel area above the aft left lavatory, and necessary precautions were taken to preclude further damage. The commenter notes that removing the corner of the electrical connector bracket and protecting the affected wire bundle with Teflon tape has provided an effective resolution to eliminate wire chafing on its airplanes. The commenter adds that the corrective action specified in the proposed AD that would require adjusting the clearance to 0.50 inch with the use of "tie-wraps," cannot be attained without creating a preload condition that could cause additional wire damage. A second commenter supports these concerns and suggests that the FAA withdraw the proposed AD and develop a more effective solution. \n\n\tWe do not agree with the commenters. We investigated the commenters' concerns and found that the airplane manufacturer did, in fact, inspect the wires in the aft left disconnect panel for a preload condition. The inspection revealed that a preload condition should not exist on the wires if they are "properly secured" with tie-wraps to obtain the 0.50-inch minimum clearance between the wires and the adjacent structure. If a preload condition is in some way created by adding the tie-wraps to the wires per the instructions in the service bulletin, the tie-wraps on the wire bundle, including the tie-wraps above the bundle, should be cut and reinstalled to obtain the 0.50-inch clearance, which will eliminate the preload condition. The manufacturer also investigated the possibility of cutting off the corner of the electrical connector bracket to eliminate the possibility of wire chafing, but there was a risk of damaging the existing wires with the tooling device used. No change to the final rule is necessary in this regard. However, if data aresubmitted that provide an alternative procedure that will offer an acceptable level of safety, we would consider this under the provisions for an alternative method of compliance, as provided in paragraph (b) of this final rule. \n\nExplanation of Editorial Change \n\n\tWe have changed the service bulletin citation throughout this final rule to exclude the Appendix (and Evaluation Form). The service bulletin recommends that report findings be submitted to the manufacturer using the Appendix of the service bulletin. However, this AD does not require that operators submit reports of inspection findings. \n\nExplanation of Change to Applicability \n\n\tWe have changed the applicability of the proposed AD to identify model designations as published in the most recent type certificate data sheet for the affected models. \n\nConclusion \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 theadoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCost Impact \n\n\tThere are approximately 1,198 airplanes of the affected design in the worldwide fleet. The FAA estimates that 586 airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the required inspection, 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 $35,160, or $60 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. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to performthe 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 thecriteria 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: