AD 98-17-06

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 repetitive inspections to detect fatigue cracking of certain fuselage skin panels, and repair, if necessary. For certain airplanes, this amendment also provides for an optional preventative modification, which, if accomplished, would terminate the repetitive inspections. This amendment is prompted by reports of fatigue cracking of certain fuselage skin panels. The actions specified by this AD are intended to prevent such fatigue cracking, which could result in reduced structural integrity of the airplane, and consequent loss of pressurization.

Final rule.

98-17-06 McDONNELL DOUGLAS: Amendment 39-10708. Docket 97-NM-20-AD. \n\n\tApplicability: Model DC-9-80 series airplanes and Model MD-88 airplanes; as listed in McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994; 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 (e) 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 addressit. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent loss of pressurization due to reduced structural integrity of the airplane, accomplish the following: \n\n\t(a)\tPrior to the accumulation of 44,500 total landings, or within 4,500 landings after the effective date of this AD, whichever occurs later: Perform a high frequency eddy current (HFEC) inspection to detect fatigue cracking of the fuselage skin panels between stations Y=160.000 and Y=200.000 at the left side of longeron 22 below the airstair door cutout, in accordance with McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994; or McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994. \n\n\t(b)\tIf no cracking is detected, accomplish the actions specified in either paragraph (b)(1) or (b)(2) of this AD, in accordance with McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994; or McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994; at the time specified. \n\n\t\t(1)\tPerform the inspection required by paragraph (a) of this AD thereafter at intervals not to exceed 4,500 landings until the requirements of paragraph (b)(2) of this AD have been accomplished. Or, \n\n\t\t(2)\tPrior to further flight, install the preventative modification in accordance with the service bulletin. Accomplishment of the preventative modification prior to detection of any cracking constitutes terminating action for the repetitive inspection requirements of this AD. \n\n\t(c)\tIf any cracking is detected within frame stations Y=160.000 and Y=200.000, accomplish the actions specified in either paragraph (c)(1) or (c)(2) of this AD, in accordance with McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994; or McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994. \n\n\t\t(1)\tAccomplish the actions specified in paragraphs (c)(1)(i), (c)(1)(ii), (c)(1)(iii), and (c)(1)(iv) of this AD at the times specified. \n\n\t\t\t(i)\tPrior to further flight, install the temporary repair in accordance with the service bulletin. \n\n\t\t\t(ii)\tWithin 3,000 landings after installation of the temporary repair, and thereafter, at intervals not to exceed 3,000 landings, perform visual inspections to detect cracking of the repaired area, in accordance with the service bulletin. \n\n\t\t\t(iii)\tWithin 4,500 landings after installation of the temporary repair, and thereafter, at intervals not to exceed 4,500 landings, perform HFEC inspections to detect cracking of any area not covered by the temporary doubler repair, in accordance with the service bulletin. \n\n\t\t\t(iv)\tWithin 8,000 landings after installation of the temporary repair, accomplish the permanent repair in accordance with the service bulletin. Accomplishment of the permanent repair constitutes terminating action for the repetitive inspection requirements of this AD. \n\n\t\t(2)\tPrior to further flight, accomplish the permanent repair in accordance with the service bulletin. Accomplishment of the permanent repair constitutes terminating action for the repetitive inspection requirements of this AD. \n\n\t(d)\tIf any cracking is detected that extends forward of station Y=160.000 or aft of station Y=200.000, prior to further flight, repair in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\t(e)\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 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 2: Information concerning the existence of approved alternative methods of compliancewith this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(f)\tSpecial 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\n\t(g)\tExcept as provided by paragraph (d) of this AD: The actions shall be done in accordance with McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994; or McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994. 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 The Boeing Company, Douglas Products Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. C1-L51 (2 60). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, 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\n\t(h)\tThis amendment becomes effective on September 18, 1998.

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-9-80 series airplanes and Model MD-88 airplanes was published in the Federal Register on March 20, 1998 (63 FR 13579). That action proposed to require repetitive inspections to detect fatigue cracking of certain fuselage skin panels, and repair, if necessary. For certain airplanes, that action also proposed to provide for an optional preventative modification, which, if accomplished, would terminate the repetitive inspections. \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\nSupport for the Proposed Rule \n\n\tSeveral commenters support the proposed rule. \n\nRequest to Refer to Latest Service Information \n\n\tOne commenter requests that the AD also refer to McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994. The FAA concurs with this request. The change notification revises certain references used in preparation of the service bulletin, and changes references to kit numbers and contents of fastener kits. The FAA has revised the final rule to state that the actions may be accomplished in accordance with either McDonnell Douglas MD-80 Service Bulletin 53-253, dated March 31, 1994, or McDonnell Douglas MD-80 Service Bulletin 53-253, as amended by Change Notification 53-253 CN1, dated April 15, 1994. \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 change previously described. The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCost ImpactThere are approximately 1,200 airplanes of the affected design in the worldwide fleet. The FAA estimates that 800 airplanes of U.S. registry will be affected by this AD, that it will take approximately 24 work hours per airplane to accomplish the required 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 $1,152,000, or $1,440 per airplane, per inspection cycle. \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. \n\nRegulatory Impact \n\n\tThe 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 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\nAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: