AD 2004-05-08

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-31 and DC-9-32 airplanes, that requires replacement of certain power relays, and subsequent repetitive cleaning, inspecting, repairing, and testing of certain replaced power relays. This action is necessary to prevent internal arcing of the left and right generator power relays, auxiliary power relays, and external power relays, and consequent smoke and/or fire in the cockpit and cabin. This action is intended to address the identified unsafe condition.

Final rule.

2004-05-08 McDonnell Douglas: Amendment 39-13502. Docket 2003-NM-32- AD. \n\n\tApplicability: Model DC-9-31 airplanes having manufacturer's fuselage numbers 1039 and 1046, and Model DC-9-32 airplanes having manufacturer's fuselage numbers 0268 and 0505; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent internal arcing of the left and right generator power relays, auxiliary power relays, and external power relays, and consequent smoke and/or fire in the cockpit and cabin, accomplish the following: \n\nInspection \n \n\t(a) Within 24 months after the effective date of this AD, perform a one-time inspection of the left and right generator power relays, auxiliary power relays, and external power relays, to determine if Sundstrand (Westinghouse) part number (P/N) 914F567-3 or -4 is installed, per Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003. \n\nReplacement or Modification/Reidentification of Any Generator Power Relay, Auxiliary Power Relay, or External Power Relay, P/N 914F567-3 \n\n\t(b) If any generator power relay, auxiliary power relay, or external power relay, Sundstrand (Westinghouse) P/N 914F567-3, is found installed during the inspection required by paragraph (a) of this AD, within 24 months after the effective date of this AD, do either action specified in paragraph (b)(1) or (b)(2) of this AD per the Accomplishment Instructions of Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003. \n\n\t(1) Replace the power relay having Sundstrand (Westinghouse) P/N 914F567-3 with either a serviceable power relay having Sundstrand (Westinghouse) P/N 9008D09 series or 914F567-4. \n\n\t(2) Modify the power relay, Sundstrand (Westinghouse) P/N 914F567-3, to a -4 configuration. \n\nMaintenance or Replacement of Any Generator Power Relay, Auxiliary Power Relay, or External Power Relay, P/N 914F567-4 \n\n \t(c) If any generator power relay, auxiliary power relay, or external power relay, Sundstrand (Westinghouse) P/N 914F567-4, is found installed during the inspection required by paragraph (a) of this AD, clean, inspect, repair, and test the relay, or replace the power relay with a serviceable power relay having Sundstrand (Westinghouse) P/N 9008D09 series or 914F567-4; per Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003; at the time specified in paragraph (c)(1) of this AD, except as provided by paragraph (c)(2) of this AD. \n\n\t(1) Within 7,000 flight hours after installation of the generator power relay, auxiliary power relay, or external power relay, Sundstrand (Westinghouse) P/N 914F567-4, or within 24 months after the effective date of this AD, whichever occurs later. \n\n\t(2) For airplanes on which the flight hours since installation of any generator power relay, auxiliary power relay, or external power relay, Sundstrand (Westinghouse) P/N 914F567-4, cannot be determined: Within 24 months after the effective date of this AD. \n\nRepetitive Maintenance of Generator Power Relay, Auxiliary Power Relay, or External Power Relay, Sundstrand (Westinghouse) P/N 914F567-4 \n\n\t(d) Before or upon the accumulation of 7,000 flight hours on any generator power relay, auxiliary power relay, or external power relay, Sundstrand (Westinghouse) P/N 914F567-4 since accomplishing the action(s) required by either paragraph (b) or (c) of this AD, as applicable, clean, inspect, repair, and test; per Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003. Thereafter, repeat these actions at intervals not to exceed the accumulation of 7,000 flight hours on the power relay. \n\nCredit for AD 2002-26-13, Amendment 39-13001 \n\n\t(e) Accomplishment of the actions specified in AD 2002-26-13 is acceptable for compliance with the requirements of this AD. \n\nAlternative Methods of Compliance \n\n\t(f) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD. \n\nIncorporation by Reference \n\n\t(g) The actions shall be done in accordance with Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003. 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 Airplanes, 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( h) This amendment becomes effective on April 7, 2004.

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-9-31 and DC-9-32 airplanes was published in the Federal Register on October 29, 2003 (68 FR 61637). That action proposed to require replacement of certain power relays, and subsequent repetitive cleaning, inspecting, repairing, and testing of certain replaced power relays. \n\nComments \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public. \n\nConclusion \n\n\tThe 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 4 airplanes of the affected design in the worldwide fleet. The FAA estimates that 2 airplanes of U.S. registry willbe affected by this AD, that it will take approximately 2 work hours per airplane to accomplish the required inspection, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $260, or $130 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\nAccordingly, 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: