AD 2003-08-02

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-90-30 airplanes. This action requires a one-time inspection for chafing or damage of the cable assemblies and follow-on modification of the cable assemblies of the powered seats located in the first-class cabin. This action is necessary to prevent chafing and damage of the cable assemblies due to contact between the cable and the metal retaining clip on the seat leg, which could result in electrical arcing and consequent smoke and/or fire in the cabin. This action is intended to address the identified unsafe condition.

Final rule; request for comments.

2003-08-02 McDonnell Douglas: Amendment 39-13113. Docket 2001-NM- 386-AD. \n\n\tApplicability: Model MD-90-30 airplanes, as listed in Boeing Alert Service Bulletin MD90-25A056, Revision 01, dated April 30, 2002; 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 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 and damage of the cable assemblies of the powered seats located in the first-class cabin, which could result in electrical arcing and consequent smoke and/or fire in the cabin, accomplish the following: \n\nOne-Time Inspection/Follow-on Modification \n\n\t(a) Within 6 months after the effective date of this AD: Do a one-time general visual inspection for chafing and damage of the cable assemblies of the powered seats located in the first-class cabin between fuselage stations Y=273.500 and Y=465.000, per Boeing Alert Service Bulletin MD90-25A056, Revision 01, dated April 30, 2002. Before further flight, do the applicable follow-on modification specified in paragraph (a)(1), (a)(2), or (a)(3) of this AD. \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) If no chafing or damage is found, modify the cable assemblies (includes installing cable assemblies and mating identification bands; installing protective sleeving and wrap; installing and routing of seat cable assemblies using improved methods; and coiling and stowing the ground wire if applicable) per Condition 1 of the service bulletin. \n\n\t(2) If any chafing or damage is found that is within the limits specified in Chapter 20 of the Standard Wiring Practices Manual (SWPM), modify the cable assemblies (includes repairing the damaged cable assemblies and doing a continuity check; installing cable assemblies and mating identification bands; installing protective sleeving and wrap; installing and routing of seat cable assemblies using improved methods; and coiling and stowing the ground wire if applicable) per Condition 2 of the service bulletin. \n\n\t(3) If any chafing or damage is found that is outside the limits specified in Chapter 20 of the SWPM, modify the cable assemblies (includes replacing the damaged wires or cable assemblies with new components, and doing a continuity check; installing cable assemblies and mating identification bands; installing protective sleeving and wrap; installing and routing of seat cable assemblies using improved methods; and coiling and stowing the ground wire if applicable) per Condition 3 of 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 MD90-25A056, Revision 01, dated April 30, 2002. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5U.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 April 30, 2003.

Boeing production personnel reported that, while securing a first-class powered seat to the floor during routine maintenance, the seat-to-seat power cable assembly shorted and arced causing a small fire under the seat. Investigation revealed that the tie-wrapped cable assembly had migrated and was contacting the metal retaining clip on the powered seat leg. This condition, if not corrected, could result in chafing and damage of the cable assemblies, consequent electrical arcing, and smoke and/or fire in the cabin. \n\nExplanation of Relevant Service Information \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin MD90-25A056, Revision 01, dated April 30, 2002, which describes procedures for a one-time visual inspection for chafing or damage of the cable assemblies and follow-on modification of the cable assemblies of the powered seats located in the first-class cabin between fuselage stations Y=273.500 and Y=465.000. The modification includesfabrication of identification bands for the left and right side seat plug cables, and accomplishment of one of the following conditions: \n\n\tCondition 1--If no chafing or damage is found, install cable assemblies and mating identification bands; install protective sleeving and wrap; install and route seat cable assemblies using improved methods; and coil and stow the ground wire; \n\n\tCondition 2--If any chafing or damage is found that is within the limits specified in Chapter 20 of the Standard Wiring Practices Manual (SWPM), repair the damaged cable assemblies and do a continuity check; install cable assemblies and mating identification bands; install protective sleeving and wrap; install and route seat cable assemblies using improved methods; and coil and stow the ground wire; or \n\n\tCondition 3--If any chafing or damage is found that is outside the limits specified in Chapter 20 of the SWPM, replace the damaged wires or cable assemblies with new components, and do a continuity check; install cable assemblies and mating identification bands; install protective sleeving and wrap; install and route seat cable assemblies using improved methods; and coil and stow the ground wire. \n\n\tThe procedures for inspection and modification described above are for Group 1 airplanes. The procedures for Group 2 airplanes are the same, except there is no coiling and stowing of the ground wire. \n\n\tAccomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. \n\nExplanation of Requirements of the Rule \n\n\tSince an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design that may be registered in the United States at some time in the future, this AD is being issued to prevent chafing and damage of the cable assemblies due to contact between the cable and the metal retaining clip on the seat leg, which could result in electrical arcing and consequent smoke and/ or fire in the cabin. This AD requires a one-time inspection for chafing or damage of the cable assemblies and follow-on modification of the cable assemblies of the powered seats located in the first-class cabin. The actions are required to be accomplished in accordance with the service bulletin described previously. \n\nCost Impact \n\n\tNone of the Model MD-90-30 airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future. \n\n\tShould an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 7 work hours to accomplish the required modification, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this AD would be $420 per airplane. \n\nDetermination of Rule's Effective Date \n\n\tSince this AD action does not affect any airplane that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, prior notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register. \n\nComments Invited \n\n\tAlthough this action is in the form of a final rule and was not preceded by notice and opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. \n\n\tSubmit comments using the following format: \n\nOrganize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues. \n\nFor each issue, state what specific change to the AD is being requested. \n\nInclude justification (e.g., reasons or data) for each request. \n\n\tComments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docketfor examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NM-386-AD." The postcard will be date stamped and returned to the commenter. \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 Accordingly, 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: