AD 2008-05-10

The FAA is superseding an existing airworthiness directive (AD) that applies to certain Boeing Model 757-200, -200PF, and -200CB series airplanes powered by Rolls-Royce engines. The existing AD currently requires repetitive inspections of the shim installation between the vertical flange and bulkhead, and repair if necessary. The existing AD also requires, for certain airplanes, an inspection for cracking of the four critical fastener holes in the horizontal flange, and repair if necessary. This new AD retains the requirements of the existing AD, and requires that the existing action be performed on airplanes without conclusive records of previous inspections. This AD results from our determination that an operator did not maintain records of previous inspections that are necessary to determine the appropriate corrective actions. We are issuing this AD to detect and correct cracks, loose and broken bolts, and shim migration in the joint between the aft torque bulkhead and thestrut-to-diagonal brace fitting, which could result in damage to the strut and consequent separation of the strut and engine from the airplane.

Final rule; request for comments.

2008-05-10 Boeing: Docket No. FAA-2008-0226; Directorate Identifier 2008-NM-016-AD; Amendment 39-15404. \n\nEffective Date \n\n\t(a) This AD becomes effective March 18, 2008. \n\nAffected ADs \n\n\t(b) This AD supersedes AD 2007-16-13. Accomplishing the actions specified in this AD terminates certain requirements of AD 2004-12- 07, amendment 39-13666. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 757-200, -200PF, and -200CB series airplanes; certificated in any category; line numbers 1 through 1048 inclusive; powered by Rolls-Royce engines. \n\nUnsafe Condition \n\n\t(d) This AD results from our determination that an operator did not maintain records of previous inspections that are necessary to determine the appropriate corrective actions. We are issuing this AD to detect and correct cracks, loose and broken bolts, and shim migration in the joint between the aft torque bulkhead and the strut-to-diagonal brace fitting, which could result in damage to the strut and consequent separation of the strut and engine from 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\nRestatement of the Requirements of AD 2007-16-13 \n\nService Bulletin Reference \n\n\n\t(f) The term "alert service bulletin,'' as used in this AD, means Boeing Alert Service Bulletin 757-54A0047, Revision 3, dated June 27, 2007. \n\nOne-Time Inspection and Repair \n\n\t(g) For airplanes identified in paragraphs (g)(1) and (g)(2) of this AD: Within 90 days after August 24, 2007 (the effective date of AD 2007-16-13), do a high frequency eddy current (HFEC) inspection for cracking of the four critical fastener holes in the horizontal flange and, before further flight, do all applicable repairs, in accordance with Part IV of the Accomplishment Instructions of the alert service bulletin, except as required by paragraph (k) of this AD. \n\t(1) Airplanes on which findings on the horizontal or vertical fasteners or the shims led to a rejection of any fastener during the actions specified in Boeing Alert Service Bulletin 757-54A0047, dated November 13, 2003; or Boeing Service Bulletin 757-54A0047, Revision 1, dated March 24, 2005. \n\t(2) Airplanes that had equivalent findings prior to Boeing Alert Service Bulletin 757-54A0047, dated November 13, 2003, except for findings on airplanes identified as Group 1, Configuration 2, in the alert service bulletin that were prior to the incorporation of Boeing Service Bulletin 757-54-0035. \n\nRepetitive Inspections and Repair \n\n\t(h) At the applicable times specified in paragraph 1.E., "Compliance,'' of the alert service bulletin, except as required by paragraphs (i) and (j) of this AD: Do the inspections specified in paragraphs (h)(1), (h)(2), and (h)(3) of this AD and, before further flight, do all applicable related investigative actions and repairs, by doing all the actions specified in Parts I andII of the Accomplishment Instructions of the alert service bulletin, except as required by paragraph (k) of this AD. \n\t(1) Do detailed inspections of the shim installations between the vertical flange and bulkhead to determine if there are signs of movement. \n\t(2) Do detailed inspections of the four fasteners in the vertical flange to determine if there are signs of movement or if there are gaps under the head or collar. \n\t(3) Do detailed inspections of the fasteners that hold the strut to the horizontal flange of the strut-to-diagonal brace fitting to determine if there are signs of movement or if there are gaps under the head or collar. \n\nExceptions To Alert Service Bulletin Procedures Specified in Paragraph (l)(2) of this AD \n\n\t(i) Where the alert service bulletin specifies a compliance time relative to "the date on this service bulletin,'' this AD requires compliance within the corresponding specified time relative to August 24, 2007. \n\t(j) Where the alert service bulletinspecifies a compliance time relative to the "date of issuance of airworthiness certificate,'' this AD requires compliance within the corresponding time relative to the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness. \n\t(k) If any crack is found during any inspection required by this AD, and the alert service bulletin specifies to contact Boeing for appropriate action: Before further flight, repair the crack using a method approved in accordance with the procedures specified in paragraph (q) of this AD. \n\nNew Requirements of This AD \n\nOne-Time Inspection/Repair for Airplanes for Which There Are No Conclusive Inspection Records \n\n\t(l) For airplanes for which there are no conclusive records showing no loose or missing fasteners during previous inspections done in accordance with the requirements of AD 2007-16-13, amendment 39-15152; or AD 2005-12-04, amendment 39-14120: Do the actions specified in paragraphs (l)(1) and (l)(2) of this AD, at the times specified in those paragraphs, as applicable. \n\t(1) Within 90 days after the effective date of this AD, do the actions specified in paragraph (g) of this AD, except as required by paragraph (k) of this AD. \n\t(2) At the applicable times specified in paragraph 1.E., "Compliance,'' of the alert service bulletin, do the actions specified in paragraph (h) of this AD, except as required by paragraphs (j) and (m) of this AD. And, before further flight, do all applicable related investigative actions and repairs, by doing all the actions specified in Parts I and II of the Accomplishment Instructions of the alert service bulletin, except as required by paragraph (k) of this AD. \n\nException To Alert Service Bulletin Procedures \n\n\t(m) Where the alert service bulletin specifies a compliance time relative to "the date on this service bulletin,'' this AD requires compliance within the corresponding specified time relative to theeffective date of this AD. \n\nCredit for Actions Done Using Previous Service Information \n\n\t(n) Except for the actions specified in paragraph (l) of this AD, actions done before the effective date of this AD in accordance with Boeing Service Bulletin 757-54A0047, Revision 1, dated March 24, 2005; or Boeing Alert Service Bulletin 757-54A0047, Revision 2, dated January 31, 2007; are considered acceptable for compliance with the corresponding actions specified in this AD. \n\t(o) An inspection and corrective actions done before June 29, 2005 (the effective date of AD 2005-12-04), in accordance with paragraph (b) or (c), as applicable, of AD 2004-12-07, are acceptable for compliance with the initial inspection requirement of paragraph (h) of this AD. \n\nAn Acceptable Method of Compliance With Certain Requirements of AD 2004-12-07 \n\n\t(p) Accomplishing the actions specified in this AD terminates the requirements specified in paragraphs (b) and (c) of AD 2004-12- 07. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(q)(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\t(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. \n\t(3) 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 Commercial Airplanes 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\t(4) AMOCs approved previously in accordance with AD 2004-12-07 are approved as AMOCs for the corresponding provisions of this AD. \n\t(5) AMOCs approved previously in accordance with AD 2005-12-04 are approved as AMOCs for the corresponding provisions of this AD. \n\t(6) AMOCs approved previously in accordance with AD 2007-16-13 are approved as AMOCs for the corresponding provisions of this AD. \n\nMaterial Incorporated by Reference \n\n\t(r) You must use Boeing Alert Service Bulletin 757-54A0047, Revision 3, dated June 27, 2007, to perform the actions that are required by this AD, unless the AD specifies otherwise. \n\t(1) On August 24, 2007 (72 FR 44753, August 9, 2007), the Director of the Federal Register approved the incorporation by reference of this service information. \n\t(2) Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the FAA, Transport AirplaneDirectorate, 1601 Lind Avenue, SW., Renton, Washington; or 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/cfr/ibr-locations.html.

Discussion \n\n\tOn July 31, 2007, we issued AD 2007-16-13, amendment 39-15152 (72 FR 44753, August 9, 2007). That AD applies to certain Boeing Model 757- 200, -200PF, and -200CB series airplanes powered by Rolls-Royce engines. That AD requires repetitive inspections of the shim installation between the vertical flange and bulkhead, and repair if necessary. That AD also requires, for certain airplanes, an inspection for cracking of the four critical fastener holes in the horizontal flange, and repair if necessary. That AD resulted from reports of cracking in the pylon under bolts that appear to be undamaged during the existing AD inspections. The actions specified in that AD are intended to detect and correct cracks, loose and broken bolts, and shim migration in the joint between the aft torque bulkhead and the strut- to-diagonal brace fitting, which could result in damage to the strut and consequent separation of the strut and engine from the airplane.Actions Since AD Was Issued \n\n\tSince we issued that AD, we have determined that some operators have not maintained records of findings (positive or negative) beyond one year of inspections conducted in accordance with AD 2007-16-13 or AD 2005-12-04 (which AD 2007-16-13 superseded). Therefore, there is no way to determine conclusively what the findings were during previous inspections. Inspection findings during previous inspections are necessary to determine what additional corrective actions need to be taken in order to adequately address the unsafe condition identified in this AD. This AD has new requirements for these airplanes that do not have records of findings during previous inspections. \n\nFAA's Determination and Requirements of This AD \n\n\tThe unsafe condition described previously is likely to exist or develop on other airplanes of the same type design. For this reason, we are issuing this AD to supersede AD 2007-16-13. This new AD retains the requirements of the existing AD. This AD also requires that the existing requirements be performed on airplanes for which there are no conclusive records of previous inspections. \n\nFAA's Justification and Determination of the Effective Date \n\n\tWe are issuing this AD to detect and correct cracks, loose and broken bolts, and shim migration in the joint between the aft torque bulkhead and the strut-to-diagonal brace fitting. These conditions could result in damage to the strut and consequent separation of the strut and engine from the airplane. Because of our requirement to promote safe flight of civil aircraft and thus, the critical need to ensure the structural integrity of the aft torque bulkhead and the strut-to-diagonal brace fitting for the engine strut and the short compliance time involved with this action, this AD must be issued immediately. \n\n\tBecause an unsafe condition exists that requires the immediate adoption of this AD, we find 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\tThis AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments before it becomes effective. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include "Docket No. FAA-2008-0226; Directorate Identifier 2008-NM-016-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments. \n\tWe will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD. \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\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\tFor the reasons discussed above, I certify that the regulation: \n\t1. Is not a "significant regulatory action'' under Executive Order 12866; \n\t2. Is not a "significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\t3. 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\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. 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 part 39 of the Federal Aviation Regulations (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 Federal Aviation Administration (FAA) amends Sec. 39.13 by removing amendment 39-15152 (72 FR 44753, August 9, 2007) and adding the following new airworthiness directive (AD):