AD 2001-26-15

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88 airplanes, that requires a detailed visual inspection of certain wires to detect chafing and preload; repair, if necessary; and modification of certain wire assemblies. This action is necessary to prevent insufficient clearance between wire assemblies and the ice protection airduct and airstair door interlock rod; chafing; and consequent arcing of wire assemblies. Such arcing could result in damage to electronic equipment and adjacent structures, or cause the insulation blankets to ignite, which could result in smoke and fire in the flight deck and main cabin. This action is intended to address the identified unsafe condition.

Final rule.

2001-26-15 McDonnell Douglas: Amendment 39-12581. Docket 2000-NM-161-AD. \n\n\tApplicability: Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88 airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD80-24A126, Revision 02, dated September 22, 1999; 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 smoke and fire in the flight deck and main cabin due to insufficient clearance between wire assemblies and the ice protection airduct and airstair door interlock rod; chafing; and consequent arcing of wire assemblies, accomplish the following: \n\nInspection and Modification \n\n\t(a) Within 6 months after the effective date of this AD, perform a detailed visual inspection of wire runs in the electrical/equipment compartment to detect chafing and preload against the airduct shroud assembly of the strake ice protection system and/or airstair door interlock rod between stations Y=148.00 and Y=160.000, in accordance with McDonnell Douglas Alert Service Bulletin MD80-24A126, Revision 02, dated September 22, 1999. \n\n\tNote 2: For the purposes of this AD, a detailed visual 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\t(1) If no chafed or preloaded wire is found, prior to further flight, install spacers, sta-straps, and tie-back wire bundles, in accordance with the service bulletin. \n\n\t\t(2) If any chafed or preloaded wire is found, prior to further flight, repair, and install spacers, sta-straps, and tie-back wire bundles, 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 Angles ACO. \n\nSpecial Flight Permit \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 McDonnell Douglas Alert Service Bulletin MD80-24A126, Revision 02, dated September 22, 1999. 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 8, 2002.

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, -83, and -87 series airplanes, and Model MD-88 airplanes was published in the Federal Register on June 5, 2001 (66 FR 30099). That action proposed to require a detailed visual inspection of certain wires to detect chafing and preload; repair, if necessary; and modification of certain wire assemblies. \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 Use a Previous Revision \n\n\tOne commenter request that the applicability of the proposed AD be revised to exclude airplanes on which the airstairs have been removed and the doors have been bolted shut. The commenter states that it is in compliance with McDonnell Douglas Service Bulletin MD80-24-126, Revision 01, dated May 14, 1998. The commenter notes McDonnell Douglas Alert Service Bulletin MD80-24A126, Revision 02, dated September 22, 1999 (which is referenced in the proposed AD as the appropriate source of service information), requires additional work, consisting of moving the airstair door to the open and closed position to ensure clearance of wiring. Therefore, the commenter concludes that the additional work in Revision 02 of the service bulletin is not necessary for its fleet. \n\n\tThe FAA does not agree with this commenter. A door bolted shut would clearly not allow inspection for wire clearance with the door in the open position. However, since the inspection required by this AD is also for clearance when the door is in the full-closed position, that part of the inspection would still be applicable. Also, additional wires need to be inspected per Revision 02 of McDonnell Douglas Alert Service Bulletin MD80-24A126. The fact that airplane structure has beenaltered does not necessarily mean that an unsafe condition has been eliminated or does not exist. Therefore, we find no change to the final rule is necessary in this regard. However, under the provisions of paragraph (b) of the final rule, we may consider requests for approval of an alternative method of compliance if sufficient data are submitted to substantiate that such a design change would provide an acceptable level of safety. \n\nRequest for Change of Level of Inspection \n\n\tThe same commenter also requests that the term "detailed visual inspection" be changed to "visual inspection," because the Common Support Data Dictionary (CSDD) has a specific definition of "detailed visual inspection" and McDonnell Douglas Service Bulletin MD80-24A126, Revision 02, does not call for this level of inspection. \n\n\tThe FAA does not concur. The definition of the "detailed visual inspection" specified in Note 2 of this AD is a standard definition that is used in all ADs that require a detailed visual inspection. We have determined that a detailed visual inspection is the appropriate level of inspection to be carried out for the unsafe condition being addressed. \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 the adoption of the rule as proposed. \n\nCost Impact \n\n\tThere are approximately 1,037 Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88 airplanes of the affected design in the worldwide fleet. The FAA estimates that 830 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 detailed visual inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the inspection required by this AD on U.S. operators is estimated to be $49,800, 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 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\nSec. 39.13 (Amended) \n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: