AD 96-22-06

This amendment adopts a new airworthiness directive (AD), applicable to all McDonnell Douglas Model DC-10-15 airplanes, that requires, among other things, inspections to detect discrepancies at various locations of pylons 1 and 3, and correction of any discrepancy found. This amendment is prompted by a report of internal structural damage to the wing engine pylon that occurred during maintenance of a Model DC-10 series airplane. The actions specified by this AD are intended to ensure the integrity of the structure and attachment of the wing engine pylon.

Final rule.

96-22-06 MCDONNELL DOUGLAS: Amendment 39-9795. Docket 96-NM-24-AD. \n\n\tApplicability: All Model DC-10-15 airplanes, 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 (k) 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 address it. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo ensure the integrity of thestructure and attachment of the wing engine pylon, accomplish the following: \n\n\t(a)\tAt each pylon removal and installation that is accomplished after the effective date of this AD: The engine and pylon shall be removed and installed separately, unless such removal or installation, or both, as an assembly is accomplished in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\t(b)\tAt each pylon removal and installation that is accomplished after the effective date of this AD: Protect the pylon aft bulkhead lug from contact with the clevis-to-wing attach bolt heads using part number (P/N) DZZ7268-1 in accordance with page 417, dated January 1, 1982, and page 427, dated May 1, 1985, of Chapter 54-00-01 of the McDonnell Douglas DC-10 Maintenance Manual. \n\n\t(c)\tPrior to further flight following any pylon reinstallation that is accomplished after the effective date of this AD: Accomplish the requirements of paragraphs (c)(1), (c)(2), and (c)(3) of this AD. \n\n\t\t(1)\tPerform an inspection of the aft pylon bulkhead to detect cracking, in accordance with page 634, dated December 1, 1979, and page 634A, dated August 1, 1990, of Chapter 54-10-11 of the McDonnell Douglas DC-10 Nondestructive Testing Manual. \n\n\t\t(2)\tPerform a visual inspection of the pylon aft spherical bearing and attaching hardware to verify the security of the nut and bolt. \n\n\t\t(3)\tPerform a visual inspection of the torque stripe for proper alignment. \n\n\t(d)\tPerform the inspections required by paragraph (e) of this AD at the later of the times specified in paragraphs (d)(1) and (d)(2) of this AD. Thereafter, repeat these inspections at intervals not to exceed 3,600 hours time-in-service or 12 months, whichever occurs later. \n\n\t\t(1)\tPrior to the accumulation of 3,600 total hours time-in-service. \n\n\t\t(2)\tWithin 3,600 hours time-in-service or 12 months after the effective date of this AD, whichever occurs later. \n\n\t(e)\tPerform the inspections required by paragraphs (e)(1) through (e)(5) of this AD at the times indicated in paragraph (d) of this AD. \n\n\t\t(1)\tPerform a visual inspection to detect cracking of the external surfaces of the thrust link forward (pylon) and aft (wing) attachment lugs, in accordance with paragraph 2.C.(1) of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(2)\tPerform a visual inspection to detect discrepancies of the upper surface of the pylon upper spar aft of station Yn=342.864, in accordance with paragraph 2.G. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(3)\tPerform a visual inspection to detect discrepancies of the center and lower (firewall) spar and spar cap angles from the aft bulkhead to the forward bulkhead, in accordance with paragraph 2.M. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(4)\tPerform an inspection for discrepancies at the various locations of the wing and tail specified on pages 601, 602, 602A, 604, 605, 606, and 608, all dated November 1, 1986; page 603, dated May 1, 1986; and pages 604A and 607, dated May 1, 1987; of Chapter 05-51-08 of the McDonnell Douglas DC-10 Maintenance Manual. Accomplish the inspections in accordance with the procedures specified on those pages of the McDonnell Douglas DC-10 Maintenance Manual. \n\n\t\t(5)\tPerform a visual inspection of the pylon aft spherical bearing and attaching hardware to verify the security of the nut and bolt, and inspect the torque stripe for alignment. \n\n\t(f)\tWithin 30 days after the effective date of this AD: Submit a pylon maintenance program, as an amendment to the maintenance program, to the assigned FAA Principal Maintenance Inspector for approval. The pylon maintenance program shall specify that, prior to the accumulation of 20,000 total hours time-in-service, or within 20,000 hours time-in-service since the last inspection, whichever occurs later, the operator will accomplish, as a minimum, the actions specified in paragraphs (f)(1)through (f)(9) of this AD. \n\n\t\t(1)\tPerform a visual inspection to detect cracking of the pylon aft bulkhead, in accordance with paragraphs 2.E. and 2.F. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979; and an eddy current inspection to detect cracking of the pylon aft bulkhead, in accordance with page 634, dated December 1, 1979, and page 634A, dated August 1, 1990, of Chapter 54-10-11 of the McDonnell Douglas DC-10 Nondestructive Testing Manual. \n\n\t\t(2)\tPerform a visual inspection to detect discrepancies of the front spar bulkhead, in accordance with paragraph 2.H. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(3)\tPerform a visual inspection to detect cracking of the attachment fitting-to-pylon forward bulkhead (footstool) of the wing front spar; perform a detailed visual inspection to detect cracking, and loose or missing fasteners, of thewing pylon attachment; and verify that the pre-load indicating (PLI) washers cannot be rotated; in accordance with paragraph 2.L. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(4)\tPerform an inspection to verify that the attach bolt PLI washers on the lower spherical bearing plug cannot be rotated; verify that no interference exists between the plug forward flange aft face, and the forward face of the spherical bearing; and perform a detailed visual inspection of the plug in situ; in accordance with paragraph 2.I. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(5)\tPerform a visual inspection to verify the condition, security, and torque stripe alignment of the plug assembly of the forward upper spherical bearing installation, in accordance with paragraph 2.J. of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(6)\tPerform a visual inspection to verify proper installation of the thrustlink bolts, nuts, and retaining washers of the thrust link installation, in accordance with paragraph 2.C.(2) of McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. \n\n\t\t(7)\tPerform an inspection of the aft spherical bearing, as specified in paragraphs (f)(7)(i) through (f)(7)(iv) of this AD. \n\n\t\t\t(i)\tRemove the aft spherical bearing through bolt. Inspect the inner bore of the bushing in situ using Magnaflux bolt and visual inspection techniques. Perform a visual inspection using a 10x (power) glass (or equivalent) to detect cracks of the forward and aft surfaces of the spherical bearing. Reinstall the through bolt. \n\n\t\t\t(ii)\tVerify that the torque of the through bolt is 1,200 to 1,300 inch-pounds. \n\n\t\t\t(iii)\tInspect the clearance of the aft spherical bearing forward face/clevis. \n\n\t\t\t(iv)\tTorque stripe the nut to bolt. \n\n\t\t(8)\tPerform an ultrasonic inspection to detect cracking of the bulkhead lug and wing clevis-to-wing attachment, including the bolts, in accordance with pages 635, 636, 638, 638A, and 638B, dated December 1, 1979; page 637, dated September 1, 1993; page 651, dated February 1, 1982; and page 652, dated August 1, 1992; of Chapter 54-10-11 of the McDonnell Douglas DC-10 Nondestructive Testing Manual. \n\n\t\t(9)\tAccomplish either paragraph (f)(9)(i) or (f)(9)(ii) of this AD. \n\n\t\t\t(i)\tPerform an X-ray inspection in situ to ensure the integrity of the steel thrust links, in accordance with page 632A, dated August 1, 1984, and page 632B, dated February 1, 1981, of the McDonnell Douglas DC-10 Nondestructive Testing Manual. Or \n\n\t\t\t(ii)\tPerform an ultrasonic inspection in situ to ensure the integrity of the steel thrust links, in accordance with page 632C, dated August 1, 1985, and page 632D, dated August 1, 1984, of the McDonnell Douglas DC-10 Nondestructive Testing Manual. \n\n\t(g)\tPrior to further flight after a pylon has been subjected to vertical or horizontal misalignment, or both (e.g., during maintenance), perform an inspection to detect cracking of the aft pylon bulkhead, in accordance with page 634, dated December 1, 1979, and page 634A, dated August 1, 1990, of Chapter 54-10-11 of the McDonnell Douglas DC-10 Nondestructive Testing Manual. \n\n\t(h)\tPrior to further flight following any event that produces high pylon loads: Perform an inspection of the pylon for structural integrity, in accordance with pages 601, 602, 602A, 604, 605, 606, and 608, dated November 1, 1986; page 603, dated May 1, 1986; and pages 604A and 607, dated May 1, 1987; of Chapter 05-51-08 of the McDonnell Douglas DC-10 Maintenance Manual. \n\n\tNOTE 2: Examples of events that produce high pylon loads, include, but are not limited to, the following: \n\nHard or overweight landings (for the purpose of this AD, overweight landings are made at aircraft weights in excess of 369,000 pounds); \n\nSevere turbulence encounters; \n\nEngine vibration that requires engine removal or critical engine failure, or both; \n\nGrounddamage (work stands, etc.); \n\nCompressor stalls requiring engine removal; and \n\n Excursions from the runway of a nature that might have imposed loads more severe than those encountered normally on the runway. \n\n\t(i)\tPrior to further flight, correct any discrepancy found during any inspection required by this AD, in accordance with a method approved by the Manager, Los Angeles ACO; the Structural Repair Manual; or McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979; as appropriate. \n\n\t(j)\tWithin 10 days after accomplishing the inspections required by this AD, report inspection results, positive or negative, to the FAA Principal Maintenance Inspector. The report shall include the information specified in paragraphs (j)(1)through (j)(5) of this AD. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.)and have been assigned OMB Control Number 2120-0056. \n\n\t\t(1)\tThe "N" number of the airplane. \n\n\t\t(2)\tThe total number of hours time-in-service accumulated on the airplane. \n\n\t\t(3)\tThe pylon number of the airplane. \n\n\t\t(4)\tThe specific paragraph (and subparagraph) of this AD that corresponds with the inspection results being reported. \n\n\t\t(5)\tSpecific inspection results: For example, the location and size of cracking, specific location of discrepant fasteners, and part numbers. \n\n\t(k)\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 3: 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(l)\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(m)\tCertain actions shall be done in accordance with McDonnell Douglas DC-10 Service Bulletin 54-74, dated December 21, 1979. 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, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of theFederal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(n)\tThis amendment becomes effective on December 11, 1996.

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 all McDonnell Douglas Model DC-10-15 airplanes was published in the Federal Register on June 19, 1996 (61 FR 31059). That action proposed to require: \n\n\t1. At each pylon removal and installation, the engine and pylon must be removed and installed separately, and the pylon aft bulkhead lug must be protected from contact with certain attach bolt heads. \n\n\t2. Performance of various repetitive inspections to detect discrepancies at various locations of pylons 1 and 3, and correction of any discrepancy found. \n\n\t3. Submission of a pylon maintenance program that includes specific repetitive inspections at intervals of 20,000 hours time-in-service. \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 the proposed rule. \n\nConclusion \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\nCost Impact \n\n\tThere are approximately 7 McDonnell Douglas Model DC-10-15 airplanes of the affected design in the worldwide fleet. The FAA estimates that 2 airplanes of U.S. registry will be affected by this AD, that it will take approximately 22 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 $2,640, or $1,320 per airplane. \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 beobtained 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: