AD 95-11-11 R1

This amendment clarifies information in an existing airworthiness directive (AD), applicable to certain McDonnell Douglas DC-10 and KC-10 series airplanes, that currently requires repetitive eddy current inspections to detect fatigue cracking of the pylon aft bulkhead flange, upper pylon box web, fitting radius, and adjacent tangent areas; and repair, if necessary. The actions specified in that AD are intended to prevent failure of the wing pylon aft bulkhead due to fatigue cracking, which could lead to separation of the engine and pylon from the airplane. This amendment clarifies the requirements of the current AD by specifying the type of initial and repetitive inspections that must be conducted. This amendment is prompted by communications received from affected operators that the current requirements of the AD are unclear.

Final rule; correction.

95-11-11 R1 McDONNELL DOUGLAS: Amendment 39-9315. Docket 94-NM-176-AD. Revises AD 95-11-11, Amendment 39-9244.\n\n\tApplicability: Model DC-10-10, -15, -30, -40, and KC-10 (military) series airplanes; as listed in McDonnell Douglas Alert Service Bulletin A54-106, Revision 2, dated November 3, 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 use the authority provided in paragraph (d) 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 failure of the wing pylon aft bulkhead due to fatigue cracking, which could lead to separation of the engine and pylon from the airplane, accomplish the following:\n\n\t(a)\tPrior to the accumulation of 1,800 landings after the effective date of this AD, conduct an eddy current bolt hole inspection and an eddy current surface probe inspection to detect fatigue cracks in the pylon aft bulkhead flange, upper pylon box web, fitting radius, and adjacent tangent areas, in accordance with McDonnell Douglas Alert Service Bulletin A54-106, Revision 2, dated November 3, 1994. Repeat the eddy current surface probe inspection thereafter at intervals not to exceed 1,800landings.\n\n\t(b)\tIf any crack is found during any inspection required by paragraph (a) of this AD, 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(c)\tAccomplishment of the gap inspection and necessary shimming in accordance with "Phase III," as specified in McDonnell Douglas Alert Service Bulletin A54-106, Revision 2, dated November 3, 1994, constitutes terminating action for the inspections required by paragraph (a) of this AD.\n\n\t(d)\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, 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(e)\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(f)\tThe inspection shall be done in accordance with McDonnell Douglas Alert Service Bulletin A54-106, Revision 2, dated November 3, 1994. This incorporation by reference was approved previously by the Director of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of July 3, 1995 (60 FR 28524, June 1, 1995). Copies may be obtained from McDonnell Douglas Corporation, 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, 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(g)\tThis amendment is effective on July 3, 1995.

On May 19, 1995, the FAA issued AD 95-11-11, amendment 39-9244 (60 FR 28524, June 1, 1995), which is applicable to certain McDonnell Douglas Model DC-10-10, -15, -30, -40, and KC-10 (military) series airplanes. That AD requires repetitive eddy current inspections to detect fatigue cracking of the pylon aft bulkhead flange, upper pylon box web, fitting radius, and adjacent tangent areas; and repair, if necessary. That action was prompted by fatigue cracking found in the wing pylon aft bulkheads on two airplanes. The actions required by that AD are intended to prevent failure of the wing pylon aft bulkhead due to fatigue cracking, which could lead to separation of the engine and pylon from the airplane.\n\n\tSince the issuance of that AD, the FAA has received communications from affected operators that the requirements for the eddy current inspections, as iterated in the AD, are unclear. Specifically, these operators have indicated that the referenced McDonnell Douglas Alert Service Bulletin A54-106, Revision 2, dated November 3, 1994, recommends that "eddy current bolt hole inspections" and "eddy current surface probe inspections" be conducted of the subject areas; however, the AD indicates that merely an "eddy current inspection" is required. Additionally, these operators point out that the service bulletin recommends that only the "eddy current surface probe inspection" be repeated; however, the AD indicates that merely the "eddy current inspection" must be repeated.\n\n\tThese operators have requested that the FAA clarify AD 95-11-11 to indicate exactly which type of eddy current inspection is to be conducted as the initial and repetitive inspection.\n\n\tIn considering this request, and upon further review of the wording of the current AD, the FAA concurs that some clarification is necessary.\n\n\tIt was the FAA's intent that the requirements of AD 95-11-11 be parallel to those actions recommended by the manufacturer in its referencedservice bulletin. The intended requirements of the AD were that affected operators would conduct an initial eddy current bolt hole inspection and eddy current surface probe inspection to detect fatigue cracks in the subject areas, and would repeat only the eddy current surface probe inspection thereafter. However, as AD 95-11-11 is currently worded, operators may incorrectly interpret the requirements as requiring that both types of eddy current inspections be repeated. Such misinterpretation could result in operators conducting unnecessary repetitive eddy current bolt hole inspections, which would be of no significant safety value and would entail incurring needless additional costs in labor and downtime.\n\n\tSince it is obvious that these requirements are not totally clear in the way that AD 95-11-11 is currently worded, the FAA has determined that the wording of paragraph (a) the AD must be revised to clarify the intent of the required actions. This action revises that paragraph to specify that, initially, both an eddy current bolt hole inspection and an eddy current surface probe inspection are required within 1,800 landings after the effective date of this AD. The eddy current surface probe inspection must then be repeated at intervals not to exceed 1,800 landings.\n\n\tAction is taken herein to clarify these requirements of AD 95-11-11 and to correctly add the AD as an amendment to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13). The effective date of the rule remains July 3, 1995.\n\n\tThe final rule is being reprinted in its entirety for the convenience of affected operators.\n\n\tSince this action only clarifies a current requirement, it has no adverse economic impact and imposes no additional burden on any person. Therefore, notice and public procedures hereon are unnecessary.\n\nList of Subjects in 14 CFR Part 39\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.\n\nAdoption of the Correction\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.\tThe authority citation for part 39 continues to read as follows:\n\nAuthority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.\n\n§ 39.13 - (Amended)\n\n\t2.\tSection 39.13 is amended by removing amendment 39-9244 (60 FR 28524, June 1, 1995), and by adding a new airworthiness directive (AD), amendment 39-9315, to read as follows: