AD 2002-24-05

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 727 series airplanes. This action requires detailed inspections to detect cracking and corrosion of the upper chord of the rear spar of the wing; and repair, if necessary. This action also requires detailed inspections to detect and permanently repair any cracking that has been previously repaired by stop-drilling. This action is necessary to prevent failure of the wing and fuel leaks in the airplane due to stress corrosion cracking of the upper chord of the rear spar. This action is intended to address the identified unsafe condition.

Final rule; request for comments.

2002-24-05 Boeing: Amendment 39-12970. Docket 2002-NM-271-AD. \n\n\tApplicability: Model 727 series airplanes, line numbers 1 through 1832 inclusive; 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 include specific proposed actions to address it. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent structural failure of the wing and fuel leaks in the airplane due to stress corrosion cracking of the upper chord of the rear spar, accomplish the following: \n\nInspection and Repair \n\n\n\t(a) For airplanes specified as "Group 1" airplanes in Boeing Alert Service Bulletin 727-57A0145, revision 2, dated October 24, 2002: Within 20 years after the date of manufacture or within 90 days after the effective date of this AD, whichever occurs later, perform an external detailed inspection for cracking, corrosion, and existing stop-drilled repairs of cracking in the upper chord on the rear spar from Wing Butt Line (WBL) 70.5 through WBL 249.3, per Boeing Alert Service Bulletin 727-57A0145, revision 2, paragraph 3.B, "Work Instructions," part 1, dated October 24, 2002. Thereafter, repeat the inspection at intervals not to exceed 2 years. \n\n\tNote 2: For the purposes of this AD, a detailed inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required." \n\n\t(1) If no cracking, corrosion, or existing stop-drilled repairs of previous cracking is detected during any inspection required by this AD, repeat the inspection at intervals not to exceed 2 years. \n\n\t(2) If any existing stop-drilled repairs of previous cracking are detected during any inspection required by this AD, before further flight, permanently repair the cracking per the alert service bulletin. \n\n\t(3) If any cracking or corrosion is detected during any inspection required by this AD that is within the limits specified in the alert service bulletin, before further flight, repair per the alert service bulletin. \n\n\t(4) If any cracking orcorrosion is detected during any inspection required by this AD that exceeds the limits specified in the alert service bulletin, and the bulletin specifies to contact Boeing for appropriate action: Before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must specifically reference this AD. \n\nAlternative Methods of Compliance \n\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, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle 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 Seattle ACO. \n\nSpecial Flight Permits \n\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\n\t(d) Except as specified in paragraph (a)(4) of this AD, the actions shall be done in accordance with Boeing Alert Service Bulletin 727-57A0145, revision 2, dated October 24, 2002. 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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; orat the Office of the Federal Register, 800 North Capitol Street, NW., Suite 700, Washington, DC. \n\nEffective Date \n\n\t(e) This amendment becomes effective on December 18, 2002.

The FAA has received reports of spanwise stress corrosion cracking of the upper chord of the rear spar of the wing between Wing Butt Line (WBL) 70.5 and the wing tip. Investigation revealed that some cracks were up to 14 inches long. Further, one of the cracks was almost long enough to jeopardize the residual strength capability of the upper chord of the rear spar. Such cracking of the upper chord of the rear spar of the wing, if not corrected, could result in structural failure of the wing and fuel leaks in the airplane. \n\nExplanation of Relevant Service Information \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin (ASB) 727-57A0145, revision 2, dated October 24, 2002. That ASB describes procedures for performing repetitive external detailed inspections on airplanes specified as "Group 1" to detect cracking and corrosion of the upper chord of the rear spar of the wing, and repair, if necessary. The ASB also describes procedures for detecting and permanently repairing any cracking that was previously repaired by stop-drilling. Additionally, the ASB describes procedures to perform high-frequency eddy current inspections (HFEC) on "Group 1" airplanes to detect cracking and corrosion of the upper chord of the rear spar and corrective action. Further, the ASB describes procedures to perform external detailed inspections and HFEC inspections on "Group 1" airplanes to detect cracking and corrosion of other areas such as the lower chord of the rear spar and the upper and lower chords of the front spar. In addition, the ASB describes procedures for certain other airplanes specified as "Group 2" airplanes that include external detailed inspections and HFEC inspections of various areas to detect cracking and corrosion; and repair, if necessary. The ASB also describes repair procedures for minor surface defects, corrosion, and cracking. \n\nExplanation of the Requirements of the Rule \n\n\tSince an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design, this AD is being issued to prevent failure of the wing and fuel leaks in the airplane due to stress corrosion cracking of the upper chord of the rear spar. This AD requires the following actions for airplanes designated as "Group 1" in Boeing Alert Service Bulletin 727-57A0145, revision 2, dated October 24, 2002: \n\nRepetitive external detailed inspections to detect cracking and corrosion of the upper chord of the rear spar of the wing, \n\nRepair of cracking and corrosion, \n\nExternal detailed inspections to detect any cracking that has been previously repaired by stop-drilling, and \n\nPermanent repair of any previously stop-drilled cracking. \n\n\nClarification of Certain Repair Conditions \n\n\tOperators should note that, although the alert service bulletin specifies that the manufacturer may be contacted for disposition of certain repair conditions, this AD requires that those conditions be accomplished per a method approved by the FAA, or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the FAA to make such findings. \n\nInterim Action \n\n\tThe actions required by this AD are considered to be interim action. The FAA is currently considering requiring additional actions specified in the alert service bulletin. However, the planned compliance time for the implementation of those actions is sufficiently long so that notice and opportunity for prior public comment will be practicable. \n\nDetermination of Rule's Effective Date \n\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\n\tAlthough this action is in the form of a final rule that involvesrequirements 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 will be 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. \n\n\tSubmit 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\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 2002-NM-271-AD." The postcard will be date stamped and returned to the commenter. \n\nRegulatory Impact \n\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\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\n\tAuthority: 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: