AD 96-25-14

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-10-10, -30, and -40 series airplanes, and KC-10 (military) series airplanes, that requires repetitive high frequency eddy current (HFEC) inspections to detect cracks in the number 4 banjo fitting on the rear spar of the vertical stabilizer, and repair and modification of the vertical stabilizer, if necessary. It also requires the installation of a modification as terminating action for the repetitive inspections. This amendment is prompted by reports of failed attach bolts and cracking found in the area of the number 4 banjo fitting, which were caused by higher than normal operating stresses. The actions specified by this AD are intended to prevent reduction in the structural integrity of this fitting due to failed bolts and cracking.

Final rule.

96-25-14 MCDONNELL DOUGLAS: Amendment 39-9857. Docket 96-NM-135-AD. \n\n\tApplicability: Model DC-10-10, -30, and -40 series airplanes, and KC-10 (military) series airplanes; as listed in McDonnell Douglas Service Bulletin DC10-54-096, Revision 03, dated February 6, 1996; 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 otherwise 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 (c) 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 requestshould include specific proposed actions to address it. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent reduction in the structural integrity of the number 4 banjo fitting on the rear spar of the vertical stabilizer, which could ultimately result in a reduction in the ability to control the airplane during flight and ground operations, accomplish the following: \n\n\t(a)\tPrior to the accumulation of 5,000 total landings, or within 1,500 landings after the effective date of this AD, whichever occurs later, perform a high frequency eddy current (HFEC) inspection to detect cracks in the upper and lower surface of the aft flange of the number 4 banjo fitting on the rear spar of the vertical stabilizer, in accordance with McDonnell Douglas Service Bulletin DC10-54-096, Revision 03, dated February 6, 1996. \n\n\t\t(1)\tIf no crack is found, repeat the HFEC inspection thereafter at intervals not to exceed 1,500 landings. \n\n\t\t(2)\tIf any crack is found, prior to further flight, repair the crack and install the modification in accordance with the service bulletin. \n\n\t(b)\tWithin 5 years after the effective date of this AD, modify the vertical stabilizer in the area of the number 4 banjo fitting on the rear spar, in accordance with any of the revisions of McDonnell Douglas Service Bulletin DC10-54-096 specified in TABLE 1 of this AD. Accomplishment of this modification constitutes terminating action for the repetitive HFEC inspections required by paragraph (a)(1) of this AD. \n\nTABLE 1\nMcDonnell Douglas Service Bulletin DC10-54-096 \n\n\nRevision Level\nIssue Date\n(Original Issue)\nMarch 23, 1989\nRevision 1\nSeptember 17, 1990 \nRevision 2\nMay 5, 1995 \nRevision 03\nFebruary 6, 1996 \n\n\t(c)\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), FAA, Transport Airplane Directorate.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 compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(d)\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(e)\tThe inspections shall be done in accordance with McDonnell Douglas Service Bulletin DC10-54-096, Revision 03, dated February 6, 1996. The modification shall be done in accordance with any of the following versions of McDonnell Douglas Service Bulletin DC10-54-096:\n\n\nRevision Level\nIssue Date \n(Original Issue) \nMarch 23, 1989\nRevision 1\nSeptember 17, 1990 \nRevision 2 \nMay 5, 1995\nRevision 03\nFebruary 6, 1996 \n\nThis 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, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Department 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(f)\tThis amendment becomes effective on January 31, 1997.

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, and -40 series airplanes, and KC-10 (military) series airplanes was published in the Federal Register on August 29, 1996 (61 FR 47375). That action proposed to require repetitive high frequency eddy current (HFEC) inspections to detect cracks in the number 4 banjo fitting on the rear spar of the vertical stabilizer, and repair and modification of the vertical stabilizer, if necessary. It also proposed to require the installation of a modification as terminating action for 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\nRequest to Allow Use of Additional Service Information \n\n\tSeveral commenters request that the proposal be revised to allow the terminating modification to be accomplished in accordance with earlier versions of McDonnell Douglas Service Bulletin DC10-54-096. Although the proposal only referenced Revision 03 of this service bulletin as the appropriate source of service information, these commenters contend that the modification as described in the original issue of the service bulletin (dated March 23, 1989), as well as Revision 01 (dated September 17, 1990) and Revision 02 (dated May 5, 1995), is equivalent to that described in Revision 03. Since certain of these commenters have already installed the modification on their airplanes in accordance with the earlier revisions of the service bulletin, they want to ensure that they will receive credit for having complied with the proposed terminating action. \n\n\tThe FAA concurs, and has included all of the revisions in final rule as acceptable sources of service information for compliance with the terminating modification requirements ofthe AD. \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 Impact \n\n\tThere are approximately 376 Model DC-10-10, -30, and -40 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 230 airplanes of U.S. registry will be affected by this AD. \n\n\tIt will take approximately 2 work hours per airplane to accomplish each required inspection; the average labor rate is $60 per work hour. Based on these figures, the cost impact of the inspection requirement on U.S. operators is estimated to be $27,600, or $120 per airplane, per inspection. \n\n\tIt will take approximately 34 hours to accomplish the terminating modification. Required partswill cost approximately $3,875 per airplane for "Group 1" airplanes, and approximately $3,427 per airplane for "Group 2" airplanes. Based on these figures, the cost impact of the modification requirement on U.S. operators is estimated to be $5,915 per Group 1 airplane and $5,467 per Group 2 airplane. \n\n\tThe cost impact figures discussed above are 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. However, the FAA has been advised that some operators have already accomplished the terminating modification on airplanes in their fleets; therefore, the future cost impact of this AD is expected to be reduced by the amount associated with each previously modified airplane. \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 theStates, 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: