AD 2000-21-04

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 767 series airplanes, that requires installation of sleeving on the 90-minute auxiliary power unit (APU) standby power feeder cable at body station 1351. This amendment is prompted by a report of damage to the 90-minute APU standby power feeder cable caused by shifting of unrestrained cargo containers during flight. The actions specified by this AD are intended to prevent damage to the 90-minute APU standby power feeder cable, which could result in arcing between the standby power feeder cable and the shroud of the APU fuel line, penetration of the fuel line shroud, and a consequent fire in the main deck floor above the aft cargo compartment.

Final rule

2000-21-04 BOEING: Amendment 39-11936. Docket 2000-NM-91-AD. \n\n\tApplicability: Model 767 series airplanes; as listed in Boeing Alert Service Bulletin 767-24A0126, dated February 24, 2000; 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 damage to the 90-minute auxiliary power unit (APU) standby power feeder cable, which could result in arcing between the standby power feeder cable and the shroud of the APU fuel line, penetration of the fuel line shroud, and a consequent fire in the main deck floor above the aft cargo compartment, accomplish the following: \n\nInstallation of Sleeving \n\n\t(a) Within 6 months after the effective date of this AD, install sleeving on the 90-minute APU standby power feeder cable at body station 1351 on the left side of the airplane, in accordance with Boeing Alert Service Bulletin 767-24A0126, dated February 24, 2000. \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, Seattle 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, Seattle ACO. \n\n\tNOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle 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 installation shall be done in accordance with Boeing Alert Service Bulletin 767-24A0126, dated February 24, 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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\nEffective Date \n\t(e) This amendment becomes effective on November 24, 2000.

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 Boeing Model 767 series airplanes was published in the Federal Register on May 12, 2000 (65 FR 30553). That action proposed to require installation of sleeving on the 90-minute auxiliary power unit (APU) standby power feeder cable at body station 1351.\n\n Comments \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. \n\nRevise Paragraph (a) of the Proposal \n\n\tThe commenter notes that paragraph (a) of the proposal states, "Within 6 months after the effective date of this AD, install sleeving on the 90-minute APU standby power feeder cable at body station 1351 on the left side of the airplane. . ." The commenter also reiterates a portion of the Discussion section that reads, "The cargocontainers damaged the 90-minute APU standby power feeder cable and the cabin floor support beam at body station 1351, on the right side of the airplane. Investigation revealed evidence of arcing between the cable and the beam." The commenter inquires as to why there is no proposed requirement for sleeving of the cable on the right-hand side of the airplane. The commenter further states that even though the fuel line is not on the right-hand side of the airplane, any cable arcing may still become a potential hazard and should be addressed. Therefore, the commenter requests that paragraph (a) of the proposal be revised to read, ". . . on the left and right sides of the airplane. . ." \n\n\tThe FAA does not concur with the commenter's request. Accomplishment of the corrective action of the APU standby power feeder cable, as required by paragraph (a) of the final rule, is to reduce the fire hazard associated with an unrestrained cargo container impacting the cable. Damaging the cable in the region specified could cause arcing against the APU fuel line shroud, which could penetrate the fuel line and result in a cabin fire. The arcing damage between the APU standby power feeder cable and the cargo floor beam, which was reported in the initial investigation, although serious in nature, was not deemed an unsafe condition or a threat to continued safe operation of the airplane. Further investigation determined that no structural or fire concerns resulted from the incident. Therefore, sleeving of the standby power feeder cable is necessary only in areas where damage to the cable may cause arcing to the APU fuel line. No change to paragraph (a) of the final rule is necessary in this regard.\n\n Conclusion \n\n\tAfter careful review of the available data, including the comment 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 151 airplanes of the affected design in the worldwide fleet. The FAA estimates that 14 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 action, 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 $840, 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\n Regulatory Impact \n\n\tThe regulationsadopted 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\n List of Subjects in 14CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \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\t1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 (Amended) \n\t2. Section 39.13 is amended by adding the following new airworthiness directive: