AD 2017-20-05

We are superseding Airworthiness Directive (AD) 2011-01-15, which applied to certain The Boeing Company Model 757-200, -200CB, and -300 series airplanes. AD 2011-01-15 required repetitive inspections for cracking of the fuselage skin of the crown skin panel along the chem-milled step at certain stringers, and repair if necessary. This AD adds repetitive inspections for cracking in additional areas, and repair if necessary; removes airplanes from the applicability; adds an optional skin panel replacement, which terminates all inspections; adds an optional preventive modification, which terminates certain inspections; and reduces the compliance time for certain inspections. This AD was prompted by reports of the initiation of new fatigue cracking in the fuselage skin of the crown skin panel along locally thinned channels adjacent to the chem-milled steps. We are issuing this AD to address the unsafe condition on these products.

Final rule.

Adoption of the Amendment \n\n\n\tAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n0 1. The authority citation for part 39 continues to read as follows: \n\n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n\n\nSec. 39.13 (Amended) \n\n0 2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 2011-01-15, Amendment 39-16572 (76 FR 1351, January 10, 2011), and adding the following new AD: \n\n2017-20-05 The Boeing Company: Amendment 39-19062; Docket No. FAA- 2016-3697; Product Identifier 2015-NM-143-AD. \n\n(a) Effective Date \n\n\n\tThis AD is effective November 6, 2017. \n\n(b) Affected ADs \n\n\n\tThis AD replaces AD 2011-01-15, Amendment 39-16572 (76 FR 1351, January 10, 2011) (''AD 2011-01-15''). \n\n(c) Applicability \n\n\n\t(1) This AD applies to The Boeing Company Model 757-200 and -300 series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. \n\t(2) Installation of Supplemental Type Certificate (STC) ST01518SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgSTC.nsf/0/38B606833BBD98B386257FAA00602538?OpenDocument&Highlight=st01518se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01518SE is installed, a ''change in product'' alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17. \n\n(d) Subject \n\n\n\tAir Transport Association (ATA) of America Code 53, Fuselage. \n\n(e) Unsafe Condition \n\n\n\tThis AD was prompted by reports of the initiation of fatigue cracking in the fuselage skin of the crown skin panel along locally thinned channels adjacent to the chem-milled steps. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin of the crown skin panel, which could result in pressureventing and consequent rapid decompression of the airplane. \n\n(f) Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(g) Repetitive Inspections \n\n\n\tDo the applicable inspections required by paragraphs (g)(1), (g)(2), and (g)(3) of this AD. \n\t(1) For all airplanes: Within the compliance time specified in paragraph (h) of this AD, do the Zone 1 inspection specified in paragraph (g)(1)(i) or (g)(1)(ii) of this AD. Repeat the applicable Part 1 or Part 2 inspection thereafter at the applicable times specified in table 1 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. Accomplishing the preventive modification specified in paragraph (k)(1) of this AD or the replacement specified in paragraph (k)(2) of this AD terminates the inspections required by this paragraph. \n\t(i) Do an external sliding probe eddy current (EC) inspection for cracking of the crown skinpanel in the applicable Zone 1 areas specified in, and in accordance with, Part 1 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. \n\t(ii) Do an external spot-probe-medium-frequency EC inspection for cracking of the crown skin panel in the applicable Zone 1 areas specified in, and in accordance with, Part 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. \n\t(2) For airplanes on which any crack is found during any inspection required by paragraph (g)(1) of this AD; or any repair is installed that covers any portion of the Zone 1 inspection area specified in Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016; or the optional Zone 1 preventive modification specified in paragraph (k)(1) of this AD is installed: At the applicable time specified in table 2 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016, except as required by paragraph (l)(1) of this AD: Do the Zone 2 inspection specified in paragraph (g)(2)(i) or (g)(2)(ii) of this AD. Repeat the applicable Part 4 or Part 5 inspection thereafter at the applicable times specified in table 2 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. Accomplishing the replacement specified in paragraph (k)(2) of this AD terminates the inspections required by this paragraph. \n\t(i) Do an external sliding probe EC inspection for cracking of the crown skin panel in the applicable Zone 2 areas specified in, and in accordance with, Part 4 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. \n\t(ii) Do an external spot-probe-medium-frequency EC inspection for cracking of the crown skin panel in the applicableZone 2 areas specified in, and in accordance with, Part 5 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. \n\t(3) For airplanes on which any crack is found during any inspection required by paragraph (g)(1) of this AD; or any repair is installed that covers any portion of the Zone 1 inspection area specified in Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016; or the optional Zone 1 preventive modification specified in paragraph (k)(1) of this AD is installed: At the applicable time specified in table 3 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016, except as required by paragraph (l)(1) of this AD, do the Zone 3 inspection specified in paragraph (g)(3)(i) or (g)(3)(ii) of this AD. Repeat the applicable Part 6 or Part 7 inspection thereafter at the applicable times specified in table3 of paragraph 1.E., \n\n((Page 45700)) \n\n''Compliance,'' of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. Accomplishing the replacement specified in paragraph (k)(2) of this AD terminates the inspections required by this paragraph. \n\t(i) Do an external sliding probe EC inspection for cracking of the crown skin panel in the applicable Zone 3 areas specified in, and in accordance with, Part 6 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. \n\t(ii) Do an external spot-probe-medium-frequency EC inspection for cracking of the crown skin panel in the applicable Zone 3 areas specified in, and in accordance with, Part 7 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. \n\n(h) Initial Compliance Time for Inspection Required by Paragraph (g)(1) of This AD \n\n\n\tWithin the applicable compliance times specified in paragraphs (h)(1), (h)(2), (h)(3), and (h)(4) of this AD, whichever occurs latest: Do the initial inspection required by paragraph (g)(1) of this AD. \n\t(1) For all airplanes: Before the accumulation of 15,000 total flight cycles. \n\t(2) For airplanes on which an external sliding probe EC inspection for Zone 1, as specified in Boeing Special Attention Service Bulletin 757-53-0097, has been done as of the effective date of this AD: Within 620 flight cycles after accomplishing the most recent external sliding probe EC inspection for Zone 1. \n\t(3) For airplanes on which an external spot-probe-medium- frequency EC inspection for Zone 1, as specified in Boeing Special Attention Service Bulletin 757-53-0097, has been done as of the effective date of this AD: Within 200 flight cycles after accomplishing the most recent external spot-probe-medium-frequency EC inspection for Zone 1. \n\t(4) For all airplanes: Within 200 flight cycles or 90 days after the effective date of this AD, whichever occurs first. \n\n(i) Post-Preventive Modification Supplemental Inspections \n\n\n\tFor airplanes on which a preventive modification has been installed as specified in Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016: At the applicable time specified in table 4 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016; do eddy current and detailed inspections for cracking of the applicable areas of the fuselage skin of the doublers, triplers, and fillers of the preventive modification, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016. Repeat the inspection thereafter at the applicable times specified in table 4 of paragraph 1.E., ''Compliance,'' of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. \n\n(j) Repair \n\n\n\tIf any cracking is found during any inspection required by paragraph (g)(1), (g)(2), (g)(3), or (i) of this AD, repair before further flight using a method approved in accordance with the procedures specified in paragraph (n) of this AD. Doing the repair ends the repetitive inspections for the repaired area only. \n\n(k) Optional Terminating Actions \n\n\n\t(1) Accomplishing the preventive modification, including doing high frequency EC open-hole inspections for cracking in the existing fastener holes, in accordance with Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53- 0097, Revision 3, dated December 2, 2016, except as required by paragraph (l)(2) of this AD, terminates the inspections required by paragraph (g)(1) of this AD, provided the preventive modification is done before further flight after accomplishing an inspection required by paragraph (g)(1) of this AD. If any cracking is found duringany high frequency EC open-hole inspection, before further flight, repair using a method approved in accordance with the procedures specified in paragraph (n) of this AD. \n\t(2) Replacing the crown skin panel between station (STA) 297 and STA 439, and stringers S-4L and S-4R, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016, or using a method approved in accordance with the procedures specified in paragraph (n) of this AD, terminates the inspections required by paragraphs (g)(1), (g)(2), and (g)(3) of this AD. \n\n(l) Exceptions to Service Information Specifications and Preventive Modification \n\n\n\t(1) Where Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016, specifies a compliance time ''after the Revision 2 date of this service bulletin,'' or ''after the Revision 3 date of this service bulletin,'' this AD requires compliance within the specified compliance time after the effective date of this AD. \n\t(2) Where Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016, specifies to contact Boeing for repair instructions: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (n) of this AD. \n\n(m) Credit for Previous Actions \n\n\n\tThis paragraph provides credit for Zone 1 inspections required by paragraph (g)(1) of this AD, if those actions were performed before the effective date of this AD using Boeing Special Attention Service Bulletin 757-53-0097, dated November 22, 2010 (which was incorporated by reference in AD 2011-01-15); Boeing Special Attention Service Bulletin 757-53-0097, Revision 1, dated January 6, 2011; or Boeing Special Attention Service Bulletin 757-53-0097, Revision 2, dated July 28, 2015. \n\n(n) Alternative Methods of Compliance (AMOCs) \n\n\n\t(1) The Manager, Los Angeles ACO Branch, FAA, has the authority to approve AMOCsfor this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (o)(1) of this AD. Information may be emailed to: 9-ANM-LAACO-AMOC-Requests@faa.gov. \n\t(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. \n\t(3) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Los Angeles ACO Branch, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\t(4) AMOCs approved for AD 2011-01-15 are approved as AMOCs for the corresponding provisions of paragraph (g) of this AD; except, as of the effective date of this AD, AMOCs that extend the initial compliance times specified in AD 2011-01-15 are no longer approved for the compliance time extension, and the compliance times required by this AD must be complied with. \n\t(5) For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (n)(5)(i) and (n)(5)(ii) apply. \n\t(i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, must be done to comply with the AD. An AMOC is required for any deviations to RC steps, including substeps and identified figures. \n\t(ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. \n\n(o) Related Information \n\n\n\t(1) For more information about this AD, contact Eric Schrieber, Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627- 5348; fax: 562-627-5210; email: Eric.Schrieber@faa.gov. \n\t(2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (p)(3) and (p)(4) of this AD. \n\n(p) Material Incorporated by Reference \n\n\n\t(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. \n\t(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. \n\n((Page 45701)) \n\n\n\t(i) Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. \n\t(ii) Reserved. \n\t(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; telephone 562-797-1717; Internet https://www.myboeingfleet.com. \n\t(4) You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221. \n\t(5) You may view this service information that is incorporated by reference 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\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2011-01-15, Amendment 39-16572 (76 FR 1351, January 10, 2011) (''AD 2011-01-15''). AD 2011-01-15 applied to certain The Boeing Company Model 757-200, -200CB, and -300 series airplanes. AD 2011-01-15 required repetitive inspections for cracking of the fuselage skin of the crown skin panel along the chem-milled step at stringers S- 4L and S-4R, from station (STA) 297 through STA 439, and repair if necessary. AD 2011-01-15 also included terminating action for the repetitive inspections of the repaired areas only. AD 2011-01-15 resulted from reports of cracking in the fuselage skin of the crown skin panel. The NPRM published in the Federal Register on February 18, 2016 (81 FR 8157) (''The NPRM''). The NPRM was prompted by reports of the initiation of new fatigue cracking in the fuselage skin of the crown skin panel along locally thinned channels adjacentto the chem- milled steps. The NPRM proposed to add repetitive inspections for cracking in additional areas, and repair if necessary. The NPRM also proposed to remove airplanes from the applicability in AD 2011-01-15. The NPRM also proposed to add an optional skin panel replacement, which would terminate all inspections, and an optional preventive modification, which would terminate certain inspections. \n\tWe issued a supplemental NPRM (SNPRM) that published in the Federal Register on May 5, 2017 (82 FR 21146). The SNPRM proposed to reduce the compliance time for certain inspections. \n\tWe are issuing this AD to correct the unsafe condition on these products. \n\nComments \n\n\n\tWe gave the public the opportunity to participate in developing this AD. The following presents the comments received on the SNPRM and the FAA's response to each comment. \n\nSupportive Comment \n\n\n\tUnited Airlines and Boeing concurred with the SNPRM. \n\nRequest for Alternative Method of Compliance (AMOC)VT Mobile Aerospace Engineering (MAE) Inc. stated that the proposed AD (in the SNPRM) affects Model 757-200 airplanes that were modified using certain VT MAE supplemental type certificates (STCs). VT MAE noted that its design at certain inspection locations is not identical to that of the Boeing STC design at those locations. Therefore, VT MAE plans to issue new service information to address the unsafe condition, and plans to request approval of an AMOC from the FAA for use of the new service information. \n\tFedEx stated that its airplanes have been modified in accordance with the VT MAE STC, and once this AMOC is approved to address this issue, FedEx will use it to comply with the requirements in the proposed AD (in the SNPRM). \n\tWe acknowledge the commenters' remarks. Under the provisions of paragraph (n) of this AD, we will consider requests for approval of an AMOC that addresses the VT MAE STCs, if appropriate data are submitted to substantiate that the method would providean acceptable level of safety. We have made no change to this AD in this regard. \n\nConclusion \n\n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD as proposed, except for minor editorial changes. We have determined that these minor changes: \n\tAre consistent with the intent that was proposed in the SNPRM for correcting the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the SNPRM. \n\nRelated Service Information Under 1 CFR Part 51 \n\n\n\tWe reviewed Boeing Special Attention Service Bulletin 757-53-0097, Revision 3, dated December 2, 2016. This service information describes procedures for repetitive external sliding probe eddy current (EC) and external spot-probe-medium-frequency EC inspections for cracking of the crown skin panel, repair, a preventive modification, and replacement of the crown skin panel. This service informationis reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section. \n\nCosts of Compliance \n\n\n\tWe estimate that this AD affects 652 airplanes of U.S. registry. \n\tWe estimate the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost on U.S. \n\tAction Labor cost Parts cost Cost per product operators ---------------------------------------------------------------------------------------------------------------- Inspections (Zone 1) (Retained 2 work-hours x $0...................... $170 per $110,840 per \n\tactions from AD $85 per hour = inspection cycle. inspection \n\t2011(dash)01(dash)15). $170 percycle. \n\tinspection cycle. Inspections (Zones 2 and 3) Up to 4 work- $0...................... Up to $340 per Up to $221,680 \n\t(new action). hours x $85 per inspection cycle. per inspection \n\thour = Up to cycle. \n\t$340 per \n\tinspection cycle. Optional modification......... Up to 615 work- Up to $26,496........... Up to $78,771.... Up to \n\thours x $85 per $51,358,692. \n\thour = Up to \n\t$52,275. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tWe have received no definitive data that enables us to provide a cost estimate for the on-condition actions or the optional replacement specified in this AD. \n\nAuthority for This Rulemaking \n\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 \n\n((Page 45699)) \n\npromoting 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\tThis AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division. \n\nRegulatory Findings \n\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 this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, \n\t(2) Is not a ''significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), \n\t(3) Will not affect intrastate aviation in Alaska, and \n\t(4) 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\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.