Airworthiness Directives; The Boeing Company Airplanes, 39513-39517 [2017-16779]

Download as PDF Federal Register / Vol. 82, No. 160 / Monday, August 21, 2017 / Rules and Regulations § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD): ■ 2017–17–06 The Boeing Company: Amendment 39–18996; Docket No. FAA–2017–0131; Product Identifier 2016–NM–186–AD. (a) Effective Date This AD is effective September 25, 2017. (b) Affected ADs None. (c) Applicability (1) This AD applies to The Boeing Company Model 737–300, –400, and –500 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 737–53A1357, dated August 9, 2016. (2) Installation of Supplemental Type Certificate (STC) ST01219SE (http:// rgl.faa.gov/Regulatory_and_Guidance_ Library/rgstc.nsf/0/ebd1cec7b301293e86257 cb30045557a/$FILE/ST01219SE.pdf) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE 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. (d) Subject Air Transport Association (ATA) of America Code 53; Fuselage. (e) Unsafe Condition This AD was prompted by a report of fatigue cracking found in a certain fuselage frame common to the water tank support intercostal clip located between certain stringers. We are issuing this AD to detect and correct cracking, which could grow in size and result in a severed frame. Multiple adjacent severed frames would result in reduced structural integrity of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. sradovich on DSK3GMQ082PROD with RULES (g) Inspection Before the accumulation of 34,000 total flight cycles or within 6,000 flight cycles after the effective date of this AD, whichever occurs later, do a high frequency eddy current (HFEC) inspection for any cracking in the fuselage frame at station (STA) 947.5 common to the water tank support intercostal clip located between stringers S–24R and S– 25R, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737–53A1357, dated August 9, 2016. (1) If no cracking is found, repeat the inspection thereafter at intervals not to exceed 12,000 flight cycles. (2) If any cracking is found: Before further flight, repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737–53A1357, dated August 9, 2016. VerDate Sep<11>2014 16:12 Aug 18, 2017 Jkt 241001 (h) Terminating Action Accomplishing the repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737–53A1357, dated August 9, 2016, terminates the inspection requirements of paragraph (g) of this AD. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, Los Angeles ACO Branch, FAA, has the authority to approve AMOCs for 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 (j) of this AD. Information may be emailed to: 9-ANMLAACO-AMOC-Requests@faa.gov. (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. (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. (4) For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (i)(4)(i) and (i)(4)(ii) of this AD apply. (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. If a step or substep is labeled ‘‘RC Exempt,’’ then the RC requirement is removed from that step or substep. An AMOC is required for any deviations to RC steps, including substeps and identified figures. (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. (j) Related Information For more information about this AD, contact Galib Abumeri, Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712–4137; phone: 562–627– 5324; fax: 562–627–5210; email: galib.abumeri@faa.gov. (k) Material Incorporated by Reference (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. PO 00000 Frm 00023 Fmt 4700 Sfmt 4700 39513 (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Alert Service Bulletin 737– 53A1357, dated August 9, 2016. (ii) Reserved. (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 90740–5600; telephone 562–797–1717; Internet https:// www.myboeingfleet.com. (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. (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/ibrlocations.html. Issued in Renton, Washington, on August 8, 2017. Dionne Palermo, Acting Director, System Oversight Division, Aircraft Certification Service. [FR Doc. 2017–17202 Filed 8–18–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2016–9520; Product Identifier 2016–NM–163–AD; Amendment 39–18987; AD 2017–16–10] RIN 2120–AA64 Airworthiness Directives; The Boeing Company Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 777 airplanes. This AD was prompted by reports of cracks on the underwing longerons. This AD requires repetitive inspections of the left and right side underwing longerons for any crack, and related investigative and corrective actions if necessary. We are issuing this AD to address the unsafe condition on these products. SUMMARY: This AD is effective September 25, 2017. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of September 25, 2017. DATES: E:\FR\FM\21AUR1.SGM 21AUR1 39514 Federal Register / Vol. 82, No. 160 / Monday, August 21, 2017 / Rules and Regulations For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110–SK57, Seal Beach, CA 90740–5600; telephone: 562–797–1717; Internet: https://www.myboeingfleet.com. 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. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA–2016– 9520. ADDRESSES: Examining the AD Docket You may examine the AD docket on the Internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2016– 9520; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800–647–5527) is Docket Management Facility, U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. Eric Lin, Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 1601 Lind Avenue SW., Renton, WA 98057– 3356; phone: 425–917–6412; fax: 425– 917–6590; email: eric.lin@faa.gov. FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: sradovich on DSK3GMQ082PROD with RULES Discussion We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 777 airplanes. The NPRM published in the Federal Register on January 3, 2017 (82 FR 54) (‘‘the NPRM’’). The NPRM was prompted by reports of cracks on the underwing longerons. The NPRM proposed to require repetitive inspections of the left and right side underwing longerons for any crack, and related investigative and corrective actions if necessary. We are issuing this AD to detect and correct cracks in the underwing longerons, which could result in fuel leakage into the forward cargo area and consequent increased risk of a fire or, in a more severe case, could adversely affect the structural integrity of the airplane. VerDate Sep<11>2014 16:12 Aug 18, 2017 Jkt 241001 New Service Information Since we issued the NPRM, Boeing has released Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017. In the NPRM, we refer to Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016, as the appropriate source of service information. Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017, corrects typographical errors, including errors in steps 3.c.(1) and 3.c.(2) of Part 1 of the Accomplishment Instructions, and provides additional access and inspection procedures. Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017, also adds a surface high frequency eddy current (HFEC) inspection of the external surface of the fuselage skin for any crack, to the inspection of the fuselage skin that is part of the underwing longeron replacement procedure specified in Part 8 and Part 9 of the Accomplishment Instructions. No additional work is necessary on airplanes on which the inspection of the fuselage skin was already done as specified in Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016. We have determined that Revision 1 is also an appropriate source of service information and have revised this AD accordingly. Comments We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA’s response to each comment. Support for the NPRM Boeing expressed support for the NPRM. Request To Delay AD Action Air France requested that we delay our AD action. The commenter pointed out that the manufacturer has not determined the root cause of underwing longeron failure and that because longeron cracking is a design defect, a design correction should only be implemented once during the life of the airplane. The commenter also pointed out that the service information would require multiple repairs that could be considered design corrections. The commenter stated that repetitive inspections should not be mandated until a final fix (design improvement) is available and that Air France believes that the safety concern (as stated in the service information) of fuel leaking into the forward cargo area could be addressed by A-Check level inspections. The commenter also indicated that they PO 00000 Frm 00024 Fmt 4700 Sfmt 4700 believe the structural integrity safety concern (as stated in the service information) could be addressed by existing inspections, specified in the Maintenance Planning Document (MPD), that are able to detect cracked longerons and surrounding related damages and are already continuously performed on the fleet. We disagree with the commenter’s request to delay this AD. The existing MPD inspections have been reviewed and do not adequately address the unsafe condition identified in this AD. Additionally, the determinations of the unsafe conditions, mitigating action, and compliance times of this AD have been coordinated with the manufacturer, and we have determined that the actions specified in this AD are required to address the unsafe condition. We have not changed this AD in this regard. Request To Extend Initial Compliance Time and Repeat Intervals Air France requested that we increase the compliance time for the initial inspection and include independent compliance times for the left and right underwing longeron inspections. United Airlines (UAL), Air France, All Nippon Airways (ANA), and Cathay Pacific Airways (CPA) also requested that we extend the intervals for the repetitive inspections to coincide with either A or C-Check level inspections. Additionally, ANA expressed concern that if cracking is found during the repetitive inspections then the consequent repairs could inadvertently extend the amount of time that the airplane is on the ground. UAL and CPA also noted the proposed compliance time would result in operational disruptions if not aligned with a C-check. Air France stated there are already inspections contained in the MPD and that the initial inspection compliance time should take into account when cracking was found. Air France also stated that there is no safety issue when there is a cracked underwing longeron and there is no fuel leak into the forward cargo area or a structural integrity issue. We disagree with the commenters’ requests. As stated previously, the existing MPD inspections have been reviewed and do not provide an acceptable level of safety for the affected airplanes for the identified unsafe condition. We have determined that the compliance times specified in this AD are necessary to address the identified unsafe conditions. However, we will consider requests for approval of alternative methods of compliance (AMOC), including extensions of the compliance times, if sufficient data is E:\FR\FM\21AUR1.SGM 21AUR1 Federal Register / Vol. 82, No. 160 / Monday, August 21, 2017 / Rules and Regulations submitted to substantiate that a different compliance time will provide an acceptable level of safety. We have not changed this AD in this regard. sradovich on DSK3GMQ082PROD with RULES Request To Exclude Certain Airplanes From the Applicability ANA requested that we exclude Boeing Model 777–200 airplanes that do not have a center fuel tank from the applicability of the proposed AD. ANA pointed out that since the Boeing Model 777–200 airplanes do not have a center fuel tank, a fuel leak from the center fuel tank and subsequent possible fire cannot occur. We disagree with the request to exclude Boeing Model 777–200 airplanes from the applicability of this AD. The possibility of a fuel leak into the forward cargo area and subsequent possible fire is not the only safety concern. Severe cases of uncorrected longeron cracking could adversely affect the structural integrity of the airplane. As stated previously, the determinations of the unsafe conditions, mitigating action, and compliance times in this AD have been coordinated with the manufacturer. We have not changed this AD in this regard. Request To Include Alternative Modified Repetitive Inspection Program ANA requested that we include an alternative modified repetitive inspection program in the NPRM. ANA specifically requested that the alternative modified repetitive inspection program match with their Ccheck level inspection program for the non-destructive inspection and for the detailed inspection at the ‘‘line maintenance’’ interval within times since certain inspections. ANA pointed out that the manufacturer has agreed that the requested alternative inspection program meets the inspection specifications in Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016. We disagree with the request to include an alternative modified repetitive inspection program in this AD. The commenter did not provide technical justification for such a change. We have determined that the compliance times specified in this AD are necessary to address the identified unsafe conditions. However, we will consider requests for approval of AMOCs, including extensions of the compliance times, if sufficient data is submitted to substantiate that a different compliance time will provide an acceptable level of safety. Additionally, operators may do the required inspections earlier than the compliance times required by the AD. For the VerDate Sep<11>2014 16:12 Aug 18, 2017 Jkt 241001 inspection options specified in the Boeing Alert Service Bulletin 777– 53A0081, an operator can change an inspection method at their discretion to meet operational needs, and the previous inspection determines the interval to the next inspection. We have not changed this AD in this regard. Request To Mandate Repair and Future Modification (for Terminating Action) as Identical Procedures Emirates requested that we mandate repair and future modification (for terminating action) as identical procedures to avoid incurring duplicate expenses. Emirates mentioned that the repair work is extensive (required resources, materials, and ground time) and the repair kit is expensive. Emirates pointed out that the manufacturer is expected to issue a modification service bulletin to terminate the inspection specified in Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016, and that the FAA is expected to mandate the terminating modification. The commenter also pointed out that the modification is expected to be extensive and require a modification kit that is also expensive, and concluded that the requirement of multiple kits for the repair and future planned modification would cause operators to incur duplicate expenses. We disagree with the request because there is currently no modification kit available even though it might be possible to mitigate the unsafe condition through a modification to the underwing longeron. The inspections and repairs required by this AD are necessary to provide an acceptable level of safety for the affected airplanes. However, as stated previously, we will consider requests for AMOCs, including those that allow for revised service information, repairs, or terminating actions, if sufficient data is submitted to substantiate that different service information, repairs, or terminating actions will provide an acceptable level of safety. We have not changed this AD in this regard. Request To Specify Alternate Special Tools ANA requested that we specifically include certain alternate special tools in the NPRM to measure the thickness of the fuel barrier sealants. The commenter indicated that they do not have the special tools that are specified in the airplane maintenance manual (AMM) (which is specified as an accepted procedure to repair the secondary fuel barrier in Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016). PO 00000 Frm 00025 Fmt 4700 Sfmt 4700 39515 We disagree that alternate special tools should be specified in this AD because this AD does not mandate using a specific tool. This AD requires operators to perform inspections and repairs in accordance with Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; or Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017. Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; and Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017, refer to a specific procedure in the AMM as an accepted procedure to repair the secondary fuel barrier. However, we do not mandate the AMM procedure in this AD; therefore, operators may repair the secondary fuel barrier using accepted methods in accordance with their maintenance or inspection program. We have not changed this AD in this regard. Request To Allow Simultaneous Replacement ANA requested that we allow simultaneous replacement of the longerons rather than completing one side before beginning work on the opposite side. ANA indicated that they prefer to start work on the opposite side when 50% final fastener installation has been completed on the initial longeron replacement. ANA also pointed out that the manufacturer has agreed that this method is structurally acceptable. We disagree that simultaneous replacement of the longerons should be included in this AD. Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; and Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017; specify that only one underwing longeron is to be removed and replaced at a time. However, as stated previously, we will consider requests for AMOCs if sufficient data is submitted to substantiate that a different method of completion will provide an acceptable level of safety. We have not changed this AD in this regard. Conclusion We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the changes described previously and minor editorial changes. We have determined that these minor changes: • Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and • Do not add any additional burden upon the public than was already proposed in the NPRM. E:\FR\FM\21AUR1.SGM 21AUR1 39516 Federal Register / Vol. 82, No. 160 / Monday, August 21, 2017 / Rules and Regulations We also determined that these changes will not increase the economic burden on any operator or increase the scope of this final rule. Related Service Information Under 1 CFR Part 51 We reviewed Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; and Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017. This service information describes procedures for repetitive detailed inspections, ultrasonic inspections, and HFEC inspections of the left and right side longerons, and related investigative and corrective actions if necessary. Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017, also includes an additional surface HFEC inspection of the external surface of the fuselage skin. This service information is 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. Costs of Compliance We estimate that this AD affects 201 airplanes of U.S. registry. We estimate the following costs to comply with this AD: ESTIMATED COSTS Action Labor cost Option 1: Detailed Inspection .......................... Option 2: Detailed and HFEC or Ultrasonic Inspection. Cost per product Parts cost Cost on U.S. operators 4 work-hours × $85 per hour = $340 per inspection cycle. $0 $340 per inspection cycle. $68,340 per inspection cycle. 12 work-hours × $85 per hour = $1,020 per inspection cycle. $0 $1,020 per inspection cycle. $205,020 per inspection cycle. We estimate the following costs to do any necessary replacements that are required based on the results of the inspection. We have no way of determining the number of aircraft that might need these replacements: ON-CONDITION COSTS Action Labor cost Parts cost Left side or right side longeron replacement ..... 102 work-hours × $85 per hour = $8,670 per side. $31,000 per side ......... We have received no definitive data that would enable us to provide cost estimates for the on-condition actions, other than the replacement, specified in this AD. According to the manufacturer, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage for affected individuals. As a result, we have included all costs in our cost estimate. sradovich on DSK3GMQ082PROD with RULES Authority for This Rulemaking Title 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. We 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 VerDate Sep<11>2014 16:12 Aug 18, 2017 Jkt 241001 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. This 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. Regulatory Findings 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. For the reasons discussed above, I certify that this AD: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, PO 00000 Frm 00026 Fmt 4700 Sfmt 4700 Cost per product $39,670 per side. (2) Is not a ‘‘significant rule’’ under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska, and (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. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: ■ Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD): ■ E:\FR\FM\21AUR1.SGM 21AUR1 Federal Register / Vol. 82, No. 160 / Monday, August 21, 2017 / Rules and Regulations 2017–16–10 The Boeing Company: Amendment 39–18987; Docket No. FAA–2016–9520; Product Identifier 2016–NM–163–AD. (a) Effective Date This AD is effective September 25, 2017. (b) Affected ADs None. (c) Applicability This AD applies to all The Boeing Company Model 777–200, –200LR, –300, –300ER, and 777F series airplanes, certificated in any category. (d) Subject Air Transport Association (ATA) of America Code 53, Fuselage and 57, Wings. (e) Unsafe Condition This AD was prompted by reports of cracks on the underwing longerons. We are issuing this AD to detect and correct cracks in the underwing longerons, which could result in fuel leakage into the forward cargo area and consequent increased risk of a fire or, in a more severe case, could adversely affect the structural integrity of the airplane. sradovich on DSK3GMQ082PROD with RULES (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Inspections Except as specified in paragraph (i)(1) of this AD, at the applicable times specified in tables 1 through 6 of paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016: Do detailed inspections for any crack of the left and right side underwing longerons; or do detailed inspections, and high frequency eddy current (HFEC) or ultrasonic inspections, as applicable, for any crack of the left and right side underwing longerons; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016, or Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017, except as required by paragraph (i)(2) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the inspections thereafter at the times specified in tables 1 through 6 of paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016, as applicable. Replacing an underwing longeron, including doing all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; or Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017; except as required by paragraph (i)(2) of this AD, terminates the repetitive inspections required by this paragraph for that longeron only. (h) Repetitive Post-Replacement Inspections and Corrective Actions For airplanes on which any longeron replacement has been done as specified in VerDate Sep<11>2014 16:12 Aug 18, 2017 Jkt 241001 Boeing Alert Service Bulletin 777–53A0081: At the applicable times specified in tables 7 through 14 of paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777– 53A0081, dated September 8, 2016, do detailed inspections of all replaced longerons for any crack, or do detailed inspections and ultrasonic inspections of all replaced longerons for any crack, and do all applicable corrective actions; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; or Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017; except as required by paragraph (i)(2) of this AD. Do all applicable corrective actions before further flight. Repeat the inspections thereafter at intervals not to exceed the applicable time specified in tables 7 through 14 of paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016. (i) Service Information Exceptions (1) Where Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016, specifies a compliance time ‘‘after the issue date of this service bulletin,’’ this AD requires compliance within the specified compliance time after the effective date of this AD. (2) Where Boeing Alert Service Bulletin 777–53A0081, dated September 8, 2016; or Boeing Alert Service Bulletin 777–53A0081, Revision 1, dated May 1, 2017; specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD. (j) Alternative Methods of Compliance (AMOCs) (1) The Manager, Seattle ACO Branch, FAA, has the authority to approve AMOCs for 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 (k) of this AD. Information may be emailed to: 9-ANMSeattle-ACO-AMOC-Requests@faa.gov. (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. (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, Seattle 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. (4) Except as required by paragraph (i)(2) of this AD: For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of PO 00000 Frm 00027 Fmt 4700 Sfmt 9990 39517 paragraphs (j)(4)(i) and (j)(4)(ii) of this AD apply. (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. If a step or sub-step is labeled ‘‘RC Exempt,’’ then the RC requirement is removed from that step or sub-step. An AMOC is required for any deviations to RC steps, including substeps and identified figures. (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. (k) Related Information For more information about this AD, contact Eric Lin, Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 1601 Lind Avenue SW., Renton, WA 98057– 3356; phone: 425–917–6412; fax: 425–917– 6590; email: eric.lin@faa.gov. (l) Material Incorporated by Reference (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. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Alert Service Bulletin 777– 53A0081, dated September 8, 2016. (ii) Boeing Alert Service Bulletin 777– 53A0081, Revision 1, dated May 1, 2017. (3) For Boeing 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 90740–5600; telephone: 562–797– 1717; Internet: https:// www.myboeingfleet.com. (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. (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/ibrlocations.html. Issued in Renton, Washington, on August 2, 2017. Jeffrey E. Duven, Director, System Oversight Division, Aircraft Certification Service. [FR Doc. 2017–16779 Filed 8–18–17; 8:45 am] BILLING CODE 4910–13–P E:\FR\FM\21AUR1.SGM 21AUR1

Agencies

[Federal Register Volume 82, Number 160 (Monday, August 21, 2017)]
[Rules and Regulations]
[Pages 39513-39517]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-16779]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9520; Product Identifier 2016-NM-163-AD; Amendment 
39-18987; AD 2017-16-10]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 777 airplanes. This AD was prompted by reports of 
cracks on the underwing longerons. This AD requires repetitive 
inspections of the left and right side underwing longerons for any 
crack, and related investigative and corrective actions if necessary. 
We are issuing this AD to address the unsafe condition on these 
products.

DATES: This AD is effective September 25, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of September 25, 
2017.

[[Page 39514]]


ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone: 562-797-1717; Internet: https://www.myboeingfleet.com. 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. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9520.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9520; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this final rule, the regulatory evaluation, any comments 
received, and other information. The address for the Docket Office 
(phone: 800-647-5527) is Docket Management Facility, U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Eric Lin, Aerospace Engineer, Airframe 
Section, FAA, Seattle ACO Branch, 1601 Lind Avenue SW., Renton, WA 
98057-3356; phone: 425-917-6412; fax: 425-917-6590; email: 
eric.lin@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to all The Boeing Company 
Model 777 airplanes. The NPRM published in the Federal Register on 
January 3, 2017 (82 FR 54) (``the NPRM''). The NPRM was prompted by 
reports of cracks on the underwing longerons. The NPRM proposed to 
require repetitive inspections of the left and right side underwing 
longerons for any crack, and related investigative and corrective 
actions if necessary. We are issuing this AD to detect and correct 
cracks in the underwing longerons, which could result in fuel leakage 
into the forward cargo area and consequent increased risk of a fire or, 
in a more severe case, could adversely affect the structural integrity 
of the airplane.

New Service Information

    Since we issued the NPRM, Boeing has released Boeing Alert Service 
Bulletin 777-53A0081, Revision 1, dated May 1, 2017. In the NPRM, we 
refer to Boeing Alert Service Bulletin 777-53A0081, dated September 8, 
2016, as the appropriate source of service information. Boeing Alert 
Service Bulletin 777-53A0081, Revision 1, dated May 1, 2017, corrects 
typographical errors, including errors in steps 3.c.(1) and 3.c.(2) of 
Part 1 of the Accomplishment Instructions, and provides additional 
access and inspection procedures. Boeing Alert Service Bulletin 777-
53A0081, Revision 1, dated May 1, 2017, also adds a surface high 
frequency eddy current (HFEC) inspection of the external surface of the 
fuselage skin for any crack, to the inspection of the fuselage skin 
that is part of the underwing longeron replacement procedure specified 
in Part 8 and Part 9 of the Accomplishment Instructions. No additional 
work is necessary on airplanes on which the inspection of the fuselage 
skin was already done as specified in Boeing Alert Service Bulletin 
777-53A0081, dated September 8, 2016. We have determined that Revision 
1 is also an appropriate source of service information and have revised 
this AD accordingly.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Support for the NPRM

    Boeing expressed support for the NPRM.

Request To Delay AD Action

    Air France requested that we delay our AD action. The commenter 
pointed out that the manufacturer has not determined the root cause of 
underwing longeron failure and that because longeron cracking is a 
design defect, a design correction should only be implemented once 
during the life of the airplane. The commenter also pointed out that 
the service information would require multiple repairs that could be 
considered design corrections. The commenter stated that repetitive 
inspections should not be mandated until a final fix (design 
improvement) is available and that Air France believes that the safety 
concern (as stated in the service information) of fuel leaking into the 
forward cargo area could be addressed by A-Check level inspections. The 
commenter also indicated that they believe the structural integrity 
safety concern (as stated in the service information) could be 
addressed by existing inspections, specified in the Maintenance 
Planning Document (MPD), that are able to detect cracked longerons and 
surrounding related damages and are already continuously performed on 
the fleet.
    We disagree with the commenter's request to delay this AD. The 
existing MPD inspections have been reviewed and do not adequately 
address the unsafe condition identified in this AD. Additionally, the 
determinations of the unsafe conditions, mitigating action, and 
compliance times of this AD have been coordinated with the 
manufacturer, and we have determined that the actions specified in this 
AD are required to address the unsafe condition. We have not changed 
this AD in this regard.

Request To Extend Initial Compliance Time and Repeat Intervals

    Air France requested that we increase the compliance time for the 
initial inspection and include independent compliance times for the 
left and right underwing longeron inspections. United Airlines (UAL), 
Air France, All Nippon Airways (ANA), and Cathay Pacific Airways (CPA) 
also requested that we extend the intervals for the repetitive 
inspections to coincide with either A or C-Check level inspections. 
Additionally, ANA expressed concern that if cracking is found during 
the repetitive inspections then the consequent repairs could 
inadvertently extend the amount of time that the airplane is on the 
ground. UAL and CPA also noted the proposed compliance time would 
result in operational disruptions if not aligned with a C-check. Air 
France stated there are already inspections contained in the MPD and 
that the initial inspection compliance time should take into account 
when cracking was found. Air France also stated that there is no safety 
issue when there is a cracked underwing longeron and there is no fuel 
leak into the forward cargo area or a structural integrity issue.
    We disagree with the commenters' requests. As stated previously, 
the existing MPD inspections have been reviewed and do not provide an 
acceptable level of safety for the affected airplanes for the 
identified unsafe condition. We have determined that the compliance 
times specified in this AD are necessary to address the identified 
unsafe conditions. However, we will consider requests for approval of 
alternative methods of compliance (AMOC), including extensions of the 
compliance times, if sufficient data is

[[Page 39515]]

submitted to substantiate that a different compliance time will provide 
an acceptable level of safety. We have not changed this AD in this 
regard.

Request To Exclude Certain Airplanes From the Applicability

    ANA requested that we exclude Boeing Model 777-200 airplanes that 
do not have a center fuel tank from the applicability of the proposed 
AD. ANA pointed out that since the Boeing Model 777-200 airplanes do 
not have a center fuel tank, a fuel leak from the center fuel tank and 
subsequent possible fire cannot occur.
    We disagree with the request to exclude Boeing Model 777-200 
airplanes from the applicability of this AD. The possibility of a fuel 
leak into the forward cargo area and subsequent possible fire is not 
the only safety concern. Severe cases of uncorrected longeron cracking 
could adversely affect the structural integrity of the airplane. As 
stated previously, the determinations of the unsafe conditions, 
mitigating action, and compliance times in this AD have been 
coordinated with the manufacturer. We have not changed this AD in this 
regard.

Request To Include Alternative Modified Repetitive Inspection Program

    ANA requested that we include an alternative modified repetitive 
inspection program in the NPRM. ANA specifically requested that the 
alternative modified repetitive inspection program match with their C-
check level inspection program for the non-destructive inspection and 
for the detailed inspection at the ``line maintenance'' interval within 
times since certain inspections. ANA pointed out that the manufacturer 
has agreed that the requested alternative inspection program meets the 
inspection specifications in Boeing Alert Service Bulletin 777-53A0081, 
dated September 8, 2016.
    We disagree with the request to include an alternative modified 
repetitive inspection program in this AD. The commenter did not provide 
technical justification for such a change. We have determined that the 
compliance times specified in this AD are necessary to address the 
identified unsafe conditions. However, we will consider requests for 
approval of AMOCs, including extensions of the compliance times, if 
sufficient data is submitted to substantiate that a different 
compliance time will provide an acceptable level of safety. 
Additionally, operators may do the required inspections earlier than 
the compliance times required by the AD. For the inspection options 
specified in the Boeing Alert Service Bulletin 777-53A0081, an operator 
can change an inspection method at their discretion to meet operational 
needs, and the previous inspection determines the interval to the next 
inspection. We have not changed this AD in this regard.

Request To Mandate Repair and Future Modification (for Terminating 
Action) as Identical Procedures

    Emirates requested that we mandate repair and future modification 
(for terminating action) as identical procedures to avoid incurring 
duplicate expenses. Emirates mentioned that the repair work is 
extensive (required resources, materials, and ground time) and the 
repair kit is expensive. Emirates pointed out that the manufacturer is 
expected to issue a modification service bulletin to terminate the 
inspection specified in Boeing Alert Service Bulletin 777-53A0081, 
dated September 8, 2016, and that the FAA is expected to mandate the 
terminating modification. The commenter also pointed out that the 
modification is expected to be extensive and require a modification kit 
that is also expensive, and concluded that the requirement of multiple 
kits for the repair and future planned modification would cause 
operators to incur duplicate expenses.
    We disagree with the request because there is currently no 
modification kit available even though it might be possible to mitigate 
the unsafe condition through a modification to the underwing longeron. 
The inspections and repairs required by this AD are necessary to 
provide an acceptable level of safety for the affected airplanes. 
However, as stated previously, we will consider requests for AMOCs, 
including those that allow for revised service information, repairs, or 
terminating actions, if sufficient data is submitted to substantiate 
that different service information, repairs, or terminating actions 
will provide an acceptable level of safety. We have not changed this AD 
in this regard.

Request To Specify Alternate Special Tools

    ANA requested that we specifically include certain alternate 
special tools in the NPRM to measure the thickness of the fuel barrier 
sealants. The commenter indicated that they do not have the special 
tools that are specified in the airplane maintenance manual (AMM) 
(which is specified as an accepted procedure to repair the secondary 
fuel barrier in Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016).
    We disagree that alternate special tools should be specified in 
this AD because this AD does not mandate using a specific tool. This AD 
requires operators to perform inspections and repairs in accordance 
with Boeing Alert Service Bulletin 777-53A0081, dated September 8, 
2016; or Boeing Alert Service Bulletin 777-53A0081, Revision 1, dated 
May 1, 2017. Boeing Alert Service Bulletin 777-53A0081, dated September 
8, 2016; and Boeing Alert Service Bulletin 777-53A0081, Revision 1, 
dated May 1, 2017, refer to a specific procedure in the AMM as an 
accepted procedure to repair the secondary fuel barrier. However, we do 
not mandate the AMM procedure in this AD; therefore, operators may 
repair the secondary fuel barrier using accepted methods in accordance 
with their maintenance or inspection program. We have not changed this 
AD in this regard.

Request To Allow Simultaneous Replacement

    ANA requested that we allow simultaneous replacement of the 
longerons rather than completing one side before beginning work on the 
opposite side. ANA indicated that they prefer to start work on the 
opposite side when 50% final fastener installation has been completed 
on the initial longeron replacement. ANA also pointed out that the 
manufacturer has agreed that this method is structurally acceptable.
    We disagree that simultaneous replacement of the longerons should 
be included in this AD. Boeing Alert Service Bulletin 777-53A0081, 
dated September 8, 2016; and Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017; specify that only one underwing longeron 
is to be removed and replaced at a time. However, as stated previously, 
we will consider requests for AMOCs if sufficient data is submitted to 
substantiate that a different method of completion will provide an 
acceptable level of safety. We have not changed this AD in this regard.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this final rule with the changes described previously and minor 
editorial changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.

[[Page 39516]]

    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this final 
rule.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016; and Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017. This service information describes 
procedures for repetitive detailed inspections, ultrasonic inspections, 
and HFEC inspections of the left and right side longerons, and related 
investigative and corrective actions if necessary. Boeing Alert Service 
Bulletin 777-53A0081, Revision 1, dated May 1, 2017, also includes an 
additional surface HFEC inspection of the external surface of the 
fuselage skin.
    This service information is 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.

Costs of Compliance

    We estimate that this AD affects 201 airplanes of U.S. registry. We 
estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Option 1:
    Detailed Inspection........  4 work-hours x $85 per               $0  $340 per            $68,340 per
                                  hour = $340 per                          inspection cycle.   inspection cycle.
                                  inspection cycle.
Option 2:
    Detailed and HFEC or         12 work-hours x $85 per              $0  $1,020 per          $205,020 per
     Ultrasonic Inspection.       hour = $1,020 per                        inspection cycle.   inspection cycle.
                                  inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacements 
that are required based on the results of the inspection. We have no 
way of determining the number of aircraft that might need these 
replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
              Action                       Labor cost              Parts cost             Cost per product
----------------------------------------------------------------------------------------------------------------
Left side or right side longeron   102 work-hours x $85 per   $31,000 per side....  $39,670 per side.
 replacement.                       hour = $8,670 per side.
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    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions, other than the 
replacement, specified in this AD.
    According to the manufacturer, some of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

Authority for This Rulemaking

    Title 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.
    We 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.
    This 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.

Regulatory Findings

    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.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):


[[Page 39517]]


2017-16-10 The Boeing Company: Amendment 39-18987; Docket No. FAA-
2016-9520; Product Identifier 2016-NM-163-AD.

(a) Effective Date

    This AD is effective September 25, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 777-200, -200LR, 
-300, -300ER, and 777F series airplanes, certificated in any 
category.

(d) Subject

    Air Transport Association (ATA) of America Code 53, Fuselage and 
57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of cracks on the underwing 
longerons. We are issuing this AD to detect and correct cracks in 
the underwing longerons, which could result in fuel leakage into the 
forward cargo area and consequent increased risk of a fire or, in a 
more severe case, could adversely affect the structural integrity of 
the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Inspections

    Except as specified in paragraph (i)(1) of this AD, at the 
applicable times specified in tables 1 through 6 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016: Do detailed inspections for any crack of the left 
and right side underwing longerons; or do detailed inspections, and 
high frequency eddy current (HFEC) or ultrasonic inspections, as 
applicable, for any crack of the left and right side underwing 
longerons; and do all applicable related investigative and 
corrective actions; in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016, or Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017, except as required by paragraph 
(i)(2) of this AD. Do all applicable related investigative and 
corrective actions before further flight. Repeat the inspections 
thereafter at the times specified in tables 1 through 6 of paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 777-53A0081, 
dated September 8, 2016, as applicable. Replacing an underwing 
longeron, including doing all applicable related investigative and 
corrective actions, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016; or Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017; except as required by paragraph 
(i)(2) of this AD, terminates the repetitive inspections required by 
this paragraph for that longeron only.

(h) Repetitive Post-Replacement Inspections and Corrective Actions

    For airplanes on which any longeron replacement has been done as 
specified in Boeing Alert Service Bulletin 777-53A0081: At the 
applicable times specified in tables 7 through 14 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016, do detailed inspections of all replaced longerons 
for any crack, or do detailed inspections and ultrasonic inspections 
of all replaced longerons for any crack, and do all applicable 
corrective actions; in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016; or Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017; except as required by paragraph 
(i)(2) of this AD. Do all applicable corrective actions before 
further flight. Repeat the inspections thereafter at intervals not 
to exceed the applicable time specified in tables 7 through 14 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
777-53A0081, dated September 8, 2016.

(i) Service Information Exceptions

    (1) Where Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016, specifies a compliance time ``after the issue 
date of this service bulletin,'' this AD requires compliance within 
the specified compliance time after the effective date of this AD.
    (2) Where Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016; or Boeing Alert Service Bulletin 777-53A0081, 
Revision 1, dated May 1, 2017; specifies to contact Boeing for 
appropriate action: Before further flight, repair using a method 
approved in accordance with the procedures specified in paragraph 
(j) of this AD.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO Branch, FAA, has the authority to 
approve AMOCs for 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 (k) of this AD. Information may be 
emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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.
    (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, Seattle 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.
    (4) Except as required by paragraph (i)(2) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (j)(4)(i) and 
(j)(4)(ii) of this AD apply.
    (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. If a step or sub-step is labeled ``RC Exempt,'' then 
the RC requirement is removed from that step or sub-step. An AMOC is 
required for any deviations to RC steps, including substeps and 
identified figures.
    (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.

(k) Related Information

    For more information about this AD, contact Eric Lin, Aerospace 
Engineer, Airframe Section, FAA, Seattle ACO Branch, 1601 Lind 
Avenue SW., Renton, WA 98057-3356; phone: 425-917-6412; fax: 425-
917-6590; email: eric.lin@faa.gov.

(l) Material Incorporated by Reference

    (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.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 777-53A0081, dated September 
8, 2016.
    (ii) Boeing Alert Service Bulletin 777-53A0081, Revision 1, 
dated May 1, 2017.
    (3) For Boeing 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 
90740-5600; telephone: 562-797-1717; Internet: https://www.myboeingfleet.com.
    (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.
    (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.

    Issued in Renton, Washington, on August 2, 2017.
Jeffrey E. Duven,
Director, System Oversight Division, Aircraft Certification Service.
[FR Doc. 2017-16779 Filed 8-18-17; 8:45 am]
 BILLING CODE 4910-13-P