AD 94-06-01

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-80 series airplanes and Model MD-88 airplanes, that requires inspection of the ceiling pressure relief panels in the cargo compartments to determine if slotted attach points are present and, if not, modification of the panels. This amendment is prompted by a report that certain panels were manufactured without the appropriate slotted attach points. The actions specified by this AD are intended to ensure that the action of the cargo compartment pressure relief panels will enable the airplane to withstand a rapid decompression caused by a hole below the compartment floor.

Final rule.

94-06-01 MCDONNELL DOUGLAS: Amendment 39-8848. Docket 93-NM-161-AD. \n\n\tApplicability: Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87) series airplanes, and Model MD-88 airplanes; as listed in McDonnell Douglas MD-80 Service Bulletin 25-335, dated April 28, 1993; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo ensure that the action of the cargo compartment ceiling relief panels will enable the airplane to withstand a rapid decompression caused by a hole below the compartment floor, accomplish the following: \n\n\t(a)\tWithin 18 months after the effective date of this AD, inspect the ceiling relief panels in the forward, mid, and aft cargo compartments to determine if slotted attach points are present, in accordance with McDonnell Douglas MD-80 Service Bulletin 25-335, dated April 28, 1993. \n\n\t\t(1)\tIf slotted attach points are present, no further action is required by this AD. \n\n\t\t(2)\tIf slotted attach points are not present on any panel, prior to further flight, modify that panel in accordance with the service bulletin. \n\n\t(b)\tAn 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). 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: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(c)\tSpecial flight permits may be issued in accordance with Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. \n\n\t(d)\tThe inspection and modification shall be done in accordance with McDonnell Douglas MD-80 Service Bulletin 25-335, dated April 28, 1993. 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 McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 90801-1771, Attention: Business Unit Manager, Technical Administrative Support, Dept. L51, M.C. 2-98. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(e)\tThis amendment becomes effective on April 11, 1994.

A proposal to amend part 39 of the Federal Aviation Regulations to include an airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9-80 series airplanes and Model MD-88 airplanes was published in the Federal Register on November 23, 1993 (58 FR 61853). That action proposed to require inspection of the ceiling pressure relief panels to determine if slotted attach points are present, and modification of the panel(s), if necessary.\n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the three comments received.\n\n\tAll commenters support the proposed rule.\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\n\tThere are approximately 1,016 Model DC-9-80 series airplanes and Model MD-88 airplanes of the affected design in the worldwide fleet. The FAA estimates that 556 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 inspection, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the inspection requirements of this AD on U.S. operators is estimated to be $30,580, or $55 per airplane.\n\n\tThe total 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.\n\n\tIf modification of a panel is necessary, accomplishing the modification will entail approximately 5.4 work hours, at an average labor rate of $55 per work hour. No additional parts will be required. Based on these figures, the total cost of impact of any necessary modification is estimated to be $297 per panel.The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.\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 14 CFR part 39 of the Federal Aviation Regulations as follows:\n\nPART 39 - AIRWORTHINESS DIRECTIVES\n\n\t1.\tThe authority citation for part 39 continues to read as follows:\n\nAuthority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.\n\n§ 39.13 - (Amended)\n\n\t2.\tSection 39.13 is amended by adding the following new airworthiness directive: