AD 2000-22-20

This amendment adopts a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9-10, -9-20, -9-30, -9-40, and -9-50 series airplanes and C-9 (military) airplanes. This action requires, among other actions, measuring the diameter of the hole counterbore of the outboard idler hinge fitting of the left and right wing flap; performing repetitive high frequency eddy current inspections (HFEC) to detect cracks at the flap idler hinge fitting, if necessary; and replacing the flap idler hinge fitting with a new like part, if any crack is detected. This action is necessary to prevent failure of the outboard flap idler hinge fitting due to fatigue cracking, which could result in a deflected flap that may cause an asymmetric lift and consequent reduced controllability and structural integrity of the airplane. This action is intended to address the identified unsafe condition.

Final rule; request for comments.

2000-22-20 MCDONNELL DOUGLAS: Amendment 39-11968. Docket 2000-NM-344-AD. \n\n\tApplicability: Model DC-9-10, -9-20, -9-30, -9-40, and -9-50 series airplanes and C-9 (military) airplanes, as listed in Boeing Alert Service Bulletin DC9-57A218, dated September 20, 2000; 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 (b) 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 includespecific proposed actions to address it. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent failure of the outboard flap idler hinge fitting due to fatigue cracking, which could result in a deflected flap that may cause an asymmetric lift and consequent reduced controllability and structural integrity of the airplane, accomplish the following: \n\nMeasurement\n\t(a) Before the accumulation of 24,000 total landings, or within 90 days after the effective date of this AD, whichever occurs later, measure the diameter of the hole counterbore of the outboard idler hinge fitting of the left and right wing flap, per Boeing Alert Service Bulletin DC9-57A218, including Appendix, dated September 20, 2000. \n\nAcceptable Measurement of 0.875 (7/8) Inch: Installation of Certain Parts\n\t\t(1) If the diameter of any hole counterbore is 0.875 (7/8) inch, before further flight, install a new nut, plain washer, and PLI washer, per the service bulletin. \n\nUnacceptable Measurement of 1.125 (1 1/8) Inches: Repetitive Inspections and Corrective Actions, If Necessary \n\t\t(2) If the diameter of any hole counterbore is 1.125 (1 1/8) inches, before further flight, do a high frequency eddy current inspection (HFEC) to detect cracks at the flap idler hinge fitting, per the service bulletin. \n\n\t\t\t(i) Condition 1. If no crack is detected, before further flight, install a new nut, plain washer, and PLI washer, per the service bulletin. Repeat the HFEC inspection every 1,000 landings until the replacement specified in paragraph (a)(2)(ii) has been done. \n\n\t\t\t(ii) Condition 2. If any crack is detected, before further flight, replace the flap idler hinge fitting with a new like part, per the service bulletin. Within 24,000 landings after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(2) of this AD. \n\nAlternative Methods of Compliance\n\t(b) An 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. 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\nSpecial Flight Permits\n\t(c) Special 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\nIncorporation by Reference\n\t(d) The actions shall be done in accordance with Boeing Alert Service Bulletin DC9-57A218, including Appendix, dated September 20, 2000. 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 Boeing Commercial Aircraft Group, Long Beach Division, 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, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\nEffective Date\n\t(e) This amendment becomes effective on November 29, 2000.

The FAA has received reports of a failed or cracked flap idler hinge fitting at the lower outboard stud location on certain McDonnell Douglas Model DC-9 series airplanes. Investigation revealed that these discrepancies were cause by fatigue cracking initiating at the lower outboard mounting hole with a 1 1/8-inch diameter counterbore. Such fatigue cracking, if not corrected, could result in failure of the outboard flap idler hinge fitting. A failed outboard flap idler hinge fitting could result in a deflected flap, which may cause an asymmetric lift and consequent reduced controllability and structural integrity of the airplane. \n\nExplanation of Relevant Service Information \n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin DC9-57A218, including Appendix, dated September 20, 2000, which describes the following procedures: \n\n\t\t1. Measuring the diameter of the hole counterbore of the outboard idler hinge fitting of the left and rightwing flap; \n\n\t\t2. Installing a new nut, plain washer, and PLI washer; \n\n\t\t3. For certain cases, performing repetitive high frequency eddy current inspections (HFEC) to detect cracks at the flap idler hinge fitting; and \n\n\t\t4. Replacing the flap idler hinge fitting with a new like part, if any crack is detected. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. \n\nExplanation of the Requirements of the Rule\n\tSince an unsafe condition has been identified that is likely to exist or develop on other McDonnell Douglas Model DC-9-10, -9-20, -9-30, -9-40, and -9-50 series airplanes and C-9 (military) airplanes series airplanes of the same type design, this AD is being issued to prevent failure of the outboard flap idler hinge fitting due to fatigue cracking, which could result in a deflected flap that may cause an asymmetric lift and consequent reduced controllability and structural integrity of the airplane. This AD requires accomplishment of the actions specified in the service bulletin described previously. \n\nDetermination of Rule's Effective Date\n\tSince a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. \n\nComments Invited\n\tAlthough this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments willbe considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. Submit comments using the following format: \n\nOrganize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues. \n\nFor each issue, state what specific change to the AD is being requested. \n\nInclude justification (e.g., reasons or data) for each request. \n\n\tComments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2000-NM-344-AD." The postcard will be date stamped and returned to the commenter. \n\nRegulatory Impact\n\tThe regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\n\tThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, 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\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment\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\t1. The authority citation for part 39 continues to read as follows: \nAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n\t2. Section 39.13 is amended by adding the following new airworthiness directive: