92-19-14 MCDONNELL DOUGLAS: Amendment 39-8372. Docket No. 92-NM-84-AD. \n\n\tApplicability: Model MD-11 series airplanes, as listed in McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, and Revision 1, dated July 16, 1992; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent skin and doubler fatigue cracking, which could cause loss of fail safe capability of the tail pylon structure, accomplish the following: \n\n\t(a)\tFor Group I airplanes, as listed in McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, prior to the accumulation of 2,100 landings or within 60 days after the effective date of this AD, whichever occurs later, visually inspect to detect cracks on the tail pylon skin and interior doubler around the pressure relief door, and install either the interim or permanent modification, as specified in paragraphs (a)(1) and (a)(2) of this AD, in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \n\n\t\t(1)\tIf no cracks are detected, prior to further flight, install either the interim modification, which consists of interim external doublers; or the permanent modification, which consists of internal doubler, frame, and stiffener. If the interim modification is installed, prior to the accumulation of 6,000 landings or within 60 days after the effective date of this AD, whichever occurs later, install the permanent modification (internal doubler, frame, and stiffener), in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \n\n\t\t(2)\tIf cracks are detected, prior to further flight, install the permanent modification, which consists of external doublers, internal doubler, frame, and stiffener, in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \n\n\t(b)\tFor Group II airplanes, as listed in McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, prior to the accumulation of 6,000 landings or within 60 days after the effective date of this AD, whichever occurs later, conduct a dye penetrant inspection for cracks of the tail pylon skin around the pressure relief door, in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \n\n\t\t(1)\tIf no cracks are found, prior to further flight, install the permanent modification, which consists of an internal doubler, frame, and stiffener, in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \n\n\t\t(2)\tIf cracks are detected, prior to further flight, install the permanent modification which consists of external doublers, internal doubler, frame, and stiffener, in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992, or Revision 1, dated July 16, 1992. \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: 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 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(e)\tThe inspections and installation shall be done in accordance with McDonnell Douglas Service Bulletin 54-17, dated February 24, 1992; or McDonnell Douglas Service Bulletin 54-17, Revision 1, dated July 16, 1992. 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 90846-0001, Attention: Business Unit Manager, Technical Publications - Technical Administrative Support, C1-L5B. 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, 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(f)\tThis amendment becomes effective on November 17, 1992.