AD 95-24-03

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-10, -30, and -40 series airplanes, and KC-10 (military) airplanes, that requires inspections to detect corrosion or cracking of the lower front spar cap and the skin panel of the horizontal stabilizer, and repair of corroded or cracked parts. This amendment also requires eventual modification of the horizontal stabilizer, which terminates the inspection requirements. This action is prompted by reports indicating that corrosion, caused by water entrapment, was found on the horizontal stabilizer. The actions specified by this AD are intended to prevent water entrapment and subsequent damage to the horizontal stabilizer, which could result in reduced controllability of the airplane.

Final rule.

95-24-03 MCDONNELL DOUGLAS: Amendment 39-9435. Docket 95-NM-49-AD. \n\n\tApplicability: Model DC-10-10, -30, and -40 airplanes, and KC-10 (military) airplanes; as listed in McDonnell Douglas Service Bulletin 55-14, Revision 6, dated January 11, 1993, 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 use the authority provided in paragraph (c) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent reduced controllability of the airplane, due to a damaged horizontal stabilizer, accomplish the following: \n\n\t(a)\tWithin one year after the effective date of this AD, perform a visual inspection to detect corrosion or cracking of the lower front spar cap and skin panel of the horizontal stabilizer, in accordance with McDonnell Douglas DC-10 Service Bulletin 55-14, Revision 5, dated August 24, 1990, or Revision 6, dated January 11, 1993. \n\n\t\t(1)\tIf no corrosion or cracking is found during this inspection, repeat this inspection thereafter at intervals not to exceed one year, until the modification required by paragraph (b) of this AD is accomplished. \n\n\t\t(2)\tIf any corrosion or cracking is found during this inspection, prior to further flight, repair the corrosion and/or cracking, and add drain holes, in accordance with Table 1 of the service bulletin. Accomplishment of these repairs and modification constitutes terminating action for the repetitive inspection requirements of this AD. \n\n\t(b)\tPerform the modification of the lower front spar cap and the skin panel of the horizontal stabilizer in accordance with McDonnell Douglas Service Bulletin 55-14, Revision 5, dated August 24, 1990, or Revision 6, dated January 11, 1993, at the applicable time specified in paragraph (b)(1) or (b)(2) of this AD. Accomplishment of this modification constitutes terminating action for the repetitive inspection requirements of this AD. \n\n\t\t(1)\tFor Model DC-10-10 airplanes: Accomplish the modification prior to the accumulation of 42,000 total landings, or within five years after the effective date of the AD, whichever occurs later. \n\n\t\t(2)\tFor Model DC-10-30 and DC-10-40 airplanes: Accomplish the modification prior to the accumulation of 30,000 total landings, or within five years after the effective date of this AD, whichever occurs later. \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.(e)\tThe actions shall be done in accordance with McDonnell Douglas Service Bulletin 55-14, Revision 5, dated August 24, 1990, or Revision 6, dated January 11, 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, 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, Los Angeles Aircraft Certification Office, Transport Airplane Directorate, 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 December 27, 1995.

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, -30, and -40 series airplanes, and KC-10 (military) airplanes was published in the Federal Register on June 13, 1995 (60 FR 31124). That action proposed to require repetitive visual inspections to detect corrosion or cracking of the lower front spar cap and the skin panel of the horizontal stabilizer, and repair of corroded or cracked parts. That action also proposed to require the eventual modification of the lower front spar cap and the lower front skin panel of the horizontal stabilizer, which would constitute terminating action for the repetitive inspection requirements. \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\n\tThe commenter supports theproposed rule. \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\n\tThere are approximately 286 Model DC-10-10, DC-10-30, and DC-10-40 airplanes, and KC- 10 (military) airplanes of the affected design in the worldwide fleet. The FAA estimates that 142 airplanes of U.S. registry will be affected by this AD, that it will take approximately 26 work hours per airplane to accomplish the required actions, 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 $221,520, or $1,560 per airplane. \n\n\tThe FAA estimates that it will take approximately 241 work hours per airplane to accomplish the terminating modification, at an average labor rate of $60 per work hour. Required parts would cost approximately $124,906 per airplane. Based on these figures, the cost impact of the terminating modification is estimated to be $19,789,972, or $139,366 per airplane. \n\n\tBased on the figures discussed above, the estimated cost impact of the requirements of this AD is expected to total $20,011,492, or $140,926 per airplane. This estimated cost impact figure 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\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 39continues to read as follows: \n\nAuthority: 49 USC 106(g), 40101, 40113, 44701. \n\n§ 39.13 - (Amended) \n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: