AD 2001-24-22

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-10-10, -10F, -30, -30F (KC-10A and KDC-10), -40, and -40F series airplanes; and Model MD-10-10F series airplanes. This AD requires an inspection of the power feeder cable assembly of the auxiliary power unit (APU) for chafing, correct type of clamps, and proper clamp installation; and corrective actions, if necessary. The actions specified by this AD are intended to prevent loss of the APU generator due to chafing of the generator power feeder cables, and consequent electrical arcing and smoke/fire in the APU compartment. This action is intended to address the identified unsafe condition.

Final rule.

2001-24-22 McDonnell Douglas: Amendment 39-12539. Docket 2001-NM-97-AD. \n\n\tApplicability: Model DC-10-10, -10F, -30, -30F (KC-10A and KDC-10), -40, and -40F series airplanes; and Model MD-10-10F series airplanes; as listed in Boeing Alert Service Bulletin DC10-24A137, Revision 01, dated May 31, 2001; 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 loss of the auxiliary power unit (APU) generator due to chafing of the generator power feeder cable and consequent electrical arcing and smoke/fire in the APU compartment, accomplish the following: \n\nInspection and Corrective Action(s), if Necessary \n\n\t(a) Within 12 months after the effective date of this AD, do a general visual inspection of the power feeder cable assembly of the APU for chafing, correct type (including part number) of clamps, and proper clamp installation, per Boeing Alert Service Bulletin DC10-24A137, Revision 01, dated May 31, 2001. \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 under normally availablelighting conditions such as daylight, hangar lighting, flashlight, or drop-light, 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\t(1) Condition 1. If no signs of wire chafing are found, and all clamps are of the correct type (including the correct part number), and are installed properly, no further action is required by this AD. \n\n\t\t(2) Condition 2. If any wire chafing, incorrect type of any clamp (including incorrect part number), or improper clamp installation is found, before further flight, do applicable corrective action(s) (e.g., repair, replace, and modify discrepant part) per the Accomplishment Instructions of the service bulletin. \n\n\tNote 3: Accomplishment of the inspection and any applicable corrective actions, per Boeing Service Bulletin DC10-24-137, dated September 15, 1987, before the effective date of this AD, is considered acceptable for compliance with the requirements of this AD. \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 4: 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 DC10-24A137, Revision 01, dated May 31, 2001. 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 January 16, 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-10-10, -30, -30F (KC-10A and KDC-10), and -40 series airplanes; and Model MD-10-10F series airplanes; was published in the Federal Register on July 23, 2001 (66 FR 38191). That action proposed to require an inspection of the power feeder cable assembly of the auxiliary power unit (APU) for chafing, correct type of clamps, and proper clamp installation; 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 Clarify Requirements and Extend Compliance Time \n\n\tThe commenters request that the proposed AD be revised to clarify whether the inspection requirement includes verifying the clamp part number. The commenters assert that the proposed AD underestimates the work hours necessary to accomplish the inspection, if the part number verification is also required. The commenters request that the compliance time be extended to accommodate the anticipated additional work hours. According to the commenters, the APU generator must be removed for easy access to the subject support cables--which are installed in an extremely confined space--to verify the part number. The commenters estimate that the inspection, including removal of the APU generator, would take 22.5 work hours. Because the task is best suited to planned multiple-day maintenance visits, the commenters anticipate extended downtime for the affected airplanes and request that the compliance time be extended from 12 months to 18 months. \n\n\tThe FAA partially concurs. In light of the possible confusion regarding certain requirements of the AD, the FAA has determined that clarification may be necessary. Therefore, paragraph (a) has been revised in this final rule to include verification of the clamp part number. \n\n\tHowever, the FAA does not concur with the request to extend the compliance time. The FAA has confirmed with the manufacturer that, while removing the APU generator might improve accessibility to the inspection area, it is not necessary. Further, as indicated in the proposed AD, the cost estimates represent only the time necessary to perform the specific actions actually required by the AD. Those figures typically do not include incidental costs, such as the time required to gain access. This AD does not require removal of the APU generator to perform the inspection. Therefore, the work hour estimate in the proposed AD is appropriate, and the proposed compliance time of 12 months is sufficient. No change to the final rule is necessary in this regard. \n\nClarification to Final Rule Requirements \n\n\tParagraph (a)(1) of the proposed AD describes the conditions for which no corrective action is required ("If nowire chafing, correct type of clamps, and proper clamp installation are found * * *"). Because of the potentially misleading description of these negative inspection findings, paragraph (a)(1) has been revised in this final rule to more accurately distinguish the conditions that require corrective action. \n\nExplanation of Change to Applicability \n\n\tThe FAA finds that Model DC-10-10F, -30F, and -40F series airplanes were not specifically identified by model in the applicability of the proposed AD; however, they were identified by manufacturer's fuselage numbers in Boeing Alert Service Bulletin DC10-24A137, Revision 01, dated May 31, 2001 (which was referenced in the applicability statement of the proposed AD for the identification of the specific affected airplanes). Therefore, the FAA has revised the applicability throughout the final rule to include Model DC-10-10F, -30F, and -40F series airplanes. \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 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 372 airplanes of the affected design in the worldwide fleet. The FAA estimates that 282 airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the 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 $16,920, 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 proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. Thecost 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: