AD 2005-07-08 ACTIVE

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 757-200 and -200PF series airplanes. This AD requires repetitive inspections and audible tap tests of the upper and lower skins of the trailing edge wedges on certain slats, and related investigative and corrective actions if necessary. This AD also provides an optional terminating action for the repetitive inspections and audible tap tests. This AD is prompted by a report of damage to the No. 4 leading edge slat. We are issuing this AD to prevent delamination of the leading edge slats, possible loss of pieces of the trailing edge wedge assembly during flight, reduction of the reduced maneuver and stall margins, and consequent reduced controllability of the airplane.

Final rule.

2005-07-08 Boeing: Amendment 39-14032. Docket No. FAA-2004-18876; Directorate Identifier 2003-NM-254-AD. \n\nEffective Date \n\n\t(a) This AD becomes effective May 5, 2005. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 757-200 and -200PF series airplanes, certificated in any category, identified in Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003. \n\nUnsafe Condition \n\n\t(d) This AD was prompted by a report of damage to the No. 4 leading edge slat. We are issuing this AD to prevent delamination of the leading edge slats, possible loss of pieces of the trailing edge wedge assembly during flight, reduction of the reduced maneuver and stall margins, and consequent reduced controllability of the airplane. \n\nCompliance \n\n\t(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. \n\nRepetitive Inspections and Tests \n\n\t(f) Within 18 months after the effective date of this AD: Do a detailed inspection and an audible tap test of the upper and lower skins of the trailing edge wedges on slats No. 2 through No. 4 inclusive and No. 7 through No. 9 inclusive, for evidence of damage or cracking, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003. Repeat the detailed inspection and audible tap test thereafter at intervals not to exceed 18 months. \n\n\tNote 1: For the purposes of this AD, a detailed inspection is: "An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required." \n\nRelated Investigative and Corrective Actions \n\n\t(g) If any damage or cracking is found during any inspection or audible tap test required by paragraph (f) of this AD: Before further flight, do the related investigative action, if applicable, and replace the affected part with a new trailing edge wedge assembly or repair the affected part, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 757- 57A0063, dated June 26, 2003. Accomplishing the replacement terminates the repetitive inspections and audible tap tests required by paragraph (f) of this AD for that wedge assembly only. \n\nActions Accomplished Previously \n\n\t(h) Previous accomplishment of all of the actions specified in the Accomplishment Instructions of Boeing Service Bulletin 757- 57A0038, Revision 5, dated July 16, 1992; or Revision 6, dated November 10, 1994; in conjunction with the use of BMS 5-137 adhesive; is acceptable for compliance with the inspection requirements of paragraph (f) of this AD. \n\nParts Installation \n\n\t(i) As of the effective date of this AD, no trailing edge wedge assembly having a part number listed in the "Existing Part Number" column of the table in paragraph 2.C.3. of Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003, may be installed on any airplane unless it has been inspected, tested, and had any necessary corrective actions accomplished in accordance with this AD. \n\nOptional Terminating Action \n\n\t(j) Replacing all trailing edge wedge assemblies with new, improved wedge assemblies in accordance with Part III of the Accomplishment Instructions of Boeing Alert Service Bulletin 757- 57A0063, dated June 26, 2003, terminates the requirements of paragraph (f) of this AD. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(k)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. \n\n\t(2) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\nMaterial Incorporated by Reference \n\n\t(l) You must use Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approves the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. For copies of the service information, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. For information on the availability of this material at the National Archives and Records Administration (NARA), call (202) 741-6030, or go to http://www.archives.gov/ federal_register/code_of_federal_regulations/ibr_locations.html. \n\n\tYou may view the AD docket at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL- 401, Nassif Building, Washington, DC.

The FAA proposed to amend 14 CFR Part 39 with an AD for certain Boeing Model 757-200 and -200PF series airplanes. That action, published in the Federal Register on August 17, 2004 (69 FR 51015), proposed to require repetitive inspections and audible tap tests of the upper and lower skins of the trailing edge wedges on certain slats, and related investigative and corrective actions if necessary. The proposed AD also provided an optional terminating action for the repetitive inspections and audible tap tests. \n\nComments \n\n\tWe provided the public the opportunity to participate in the development of this AD. We have considered the comments that have been submitted on the proposed AD. \n\nSupportive Comment \n\n\tOne commenter supports the proposed AD. \n\nRequest To Correct Typographical Error in Applicability \n\n\tOne commenter requests that the typographical error in paragraph (c), Applicability, of the proposed AD, be corrected. The Applicability in the proposed AD states that the AD applies to Boeing Model 737-200 and -200F series airplanes, as listed in Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003. The commenter states that the reference to Model 737-200 and -200F series airplanes should be corrected to avoid confusion between the referenced service bulletin and proposed AD. \n\n\tWe agree and the Applicability section of this AD has been corrected to reference "Boeing Model 757-200 and -200PF series airplanes identified in Boeing Alert Service Bulletin 757-57A0063. * * *" We discovered this error after the proposed AD was published. We find that our intent in the proposed AD was clear, as all other references throughout the proposed AD were correct, and the referenced service bulletin applies to Boeing Model 757-200 and -200PF series airplanes. Thus, we find no reason to re-open the comment period. \n\nRequest To Clarify Applicability \n\n\tThe Air Transport Association (ATA) states that its member airlines concur withthe intent of the proposed AD, but that the applicability of the proposed AD is unclear. The commenter notes that actions specified in the proposed AD overlap or duplicate the requirements of AD 90-23-06, amendment 39-6794. The commenter also states that several slat wedge configurations exist in in-service airplanes as a result of AD 91-22-51, amendment 39-8129, and several other service bulletins that address trailing edge wedges. The commenter contends that the applicability of the proposed AD is unclear with respect to these configurations, and recommends that we revise the proposed AD to clearly state the applicability with respect to the various configurations resulting from the aforementioned airworthiness directives and service bulletins. \n\n\tWe do not agree that the applicability of this AD requires revision. The applicability of this AD states that the AD applies to Boeing Model 757-200 and -200PF series airplanes, certificated in any category, identified in Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003. The effectivity in that service bulletin is all Boeing Model 757 series airplanes with line numbers 1 through 139 inclusive. This AD addresses line numbers 1 through 139 inclusive, regardless of configuration. Also, the airplane applicability for AD 91-22-51 has different line numbers from those in this AD. The applicability for that AD is Boeing Model 757 series airplanes, line numbers 140 through 335. We have not changed this AD regarding this issue. \n\nRequest To Give Credit for Actions Accomplished Previously \n\n\tOne commenter requests that the proposed AD be revised to indicate that actions accomplished previously in accordance with Boeing Service Bulletin 757-57A0038 or 757-57A0045 are acceptable for compliance with the requirements of the proposed AD. The commenter states that the actions described in those service bulletins have the same results as the actions described in Boeing Alert Service Bulletin 757-57A0063, dated June 26, 2003. \n\n\tService Bulletins With Similar Actions \n\n\nService Bulletin-\nDated- \nIs cited in- \nAs the appropriate source of service information for- \nBoeing Alert Service \nBulletin 757-57A0063. \nJune 26, 2003 ........................... \nThe proposed AD ..................... \nInspecting, repairing, and re-\nplacing trailing edge wedges. \nBoeing Service Bulletin \n757-57A0038, Revision 2. \nOctober 10, 1990 ...................... \nAD 90-23-06, amendment 39- 6794. \nInspecting, repairing, and re-\nplacing trailing edge wedges. \nBoeing Service Bulletin 757-57A0045 ...... \nOctober 16, 1991 ...................... \nAD 91-22-51, amendment 39- 8129. \nRepetitive detailed inspections of the trailing edge wedges of slats 1 through 4 and 7 through 10. \n\n\tWe agree that accomplishment of the actions specified in Boeing Service Bulletin 757-57A0038, Revision 5, dated July 16, 1992, or Revision 6, dated November 10, 1994, only, are acceptable for compliance with the requirements ofthis AD. We do not agree that accomplishment of the actions specified in Boeing Service Bulletin 757- 57A0045 is acceptable for compliance with the requirements of this AD. As stated previously, the applicability of AD 91-22-51 is Boeing Model 757 series airplanes, line numbers 140 through 335 inclusive, and the applicability of this AD is line numbers 1 through 139 inclusive. \n\n\tWe have included a new paragraph (h) in this AD, and reidentified the subsequent paragraphs accordingly. Paragraph (h) specifies that accomplishment of the actions in the Accomplishment Instructions of Boeing Service Bulletin 757-57A0038, Revision 5 or Revision 6 only, in conjunction with the use of BMS 5-137 adhesive, is acceptable for compliance with the requirements of this AD. \n\nRequest To Revise Compliance Time for Repetitive Inspections and Tests \n\n\n\tOne commenter requests an extension of the compliance time from 18 months to 24 months for the repetitive detailed inspections and audible tap testsof the upper and lower skins of the trailing edge wedges. The commenter states that it performs maintenance checks ("C-checks") on its fleet every 24 months. The commenter also states that a compliance time of 18 months would require special maintenance visits in addition to the normally scheduled "C-checks," and the associated costs and downtime would be considerable. The commenter has reviewed its maintenance program, and the subject slats are currently inspected every 48 months. A review of the associated maintenance task cards did not reveal any discrepancies. The commenter notes that this change to the proposed AD would prevent operators from having to request approval of an AMOC for the proposed AD. \n\n\tWe do not agree with the commenter's request to extend the compliance time. In developing an appropriate compliance time for this AD, we considered the urgency associated with the subject unsafe condition, the manufacturer's recommended compliance time, and the practical aspectof accomplishing the required inspections within a period of time that corresponds to the normal scheduled maintenance program for most affected operators. However, according to the provisions of paragraph (k) of this AD, we may approve a request to adjust the compliance time if the request includes data that prove that the new compliance time would provide an acceptable level of safety. \n\nExplanation of Additional Change to This AD \n\n\tSince the publication of the proposed AD, Boeing has received a Delegation Option Authorization (DOA). We have revised this AD to delegate the authority to approve an AMOC for any repair required by this AD to the Authorized Representative for the Boeing DOA Organization rather than the Designated Engineering Representative. \n\nConclusion \n\n\tWe have carefully reviewed the available data, including the comments that have been submitted, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCosts of Compliance \n\n\tThis AD affects about 139 airplanes worldwide. The following table provides the estimated costs for U.S. operators to comply with this AD. \n\n\tEstimated Costs \n\n\nAction \nWork hours \nAverage labor rate per hour \nParts \nCost per airplane \nNumber of U.S.-\nregistered airplanes \nFleet cost \n\n\n\n\n\n\n\n\n\n\n\n\n\n\nInspection test, per inspection \ncycle. \n6 (1 work hour per slat, 6 slats per airplane.). \n$65 \nNone \n$390, per inspection/ test cycle. \n\n97 \n$37,830, per inspection/test cycle \n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\n\tWe are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements." Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatoryaction" under Executive Order 12866; \n\n\t(2) Is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t(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. \n\n\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD. See the ADDRESSES section for a location to examine the regulatory evaluation. \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\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):

For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124- 2207. You can examine this information at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html . \n\n\tDocket: The AD docket contains the proposed AD, comments, and any final disposition. You can examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647- 5227) is located on the plaza level of the Nassif Building at the U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, Washington, DC. This docket number is FAA-2004-18876; the directorate identifier for this docket is 2003-NM-254-AD.

Dennis Stremick, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6450; fax (425) 914-6590.